# Knurling advice?



## PCC (May 9, 2012)

The following three pictures show attempts at knurling. All were done on the same lathe using the same cutting wheels.









The real surprise is this:




Now, I can understand what happened in the second photo, but, what happened in the third? If one wheel is cutting just so wouldn't the other one do the same? How do I ensure that I get consistent results with my scissors type knurling tool?


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## mohanjude (May 9, 2012)

I get this all the time when I try knurling. I am guessing it has got to be the tool. I have adjusted the height etc and get variable results

I think I am going to take advice from the other thread that is active at the moment and invest in a better knurling tool


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## precisionworks (May 9, 2012)

PCC said:


> ... what happened in the third? If one wheel is cutting just so wouldn't the other one do the same? How do I ensure that I get consistent results with my scissors type knurling tool?


Machinery's Handbook is always a good place to start. Discussed is _Tracking Correction Factor Q:

_To calculate Q take the CPN <CPM> = tracking correction factor.

CPN = circular pitch on nominal diameter = pi / P
CPM = circular pitch on major diameter = pi x D / t
P = diametral pitch of knurl
D = nominal diameter of knurl=t/P
t = # of teeth on knurl =P x D
Dm = major diameter of knurl=D-(tQ / pi)

Then go to Table 2 in the same section to apply the result.

Good reference info from Accu-Trak


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## PCC (May 9, 2012)

Thanks, precisionworks, I guess I need to get a copy of that book.

I gave it a lot of thought and I think I may have figured it out. The third picture is what happens when knurling and happens because we stopped too soon. The one wheel dug in and found its groove while the other one was still trying to find it. The first wheel probably would have stopped digging allowing the second wheel to find its groove. More pressure and rotations probably would have given me the desired results. 

Thanks, guys!


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## Anglepoise (May 9, 2012)

Knurling is one area in machining that can be the most frustrating. First off is the equipment. For a small machine, the scissor style of knurler is the way to go. However it must be rigid, well made and preferably have high quality American made knurling wheels. 

Then you have to deal with the two separate camps in regard to tracking error. One camp maintains that the outer diameter must be turned to a very exact dimension before knurling and the other thinks this is all 'rubbish' and maintains that you just apply pressure and go for it.
Machining forums are full of lengthy posts subscribing to one or the other opinion.

In Europe, cut knurling is practiced pretty much exclusively,and is growing in popularity over here. Sadly equipment is expensive ( $400+ ) but worth every penny if you are knurling every day. There have been some very good discussions on this site and definitely worth looking back and searching the archives.


Read as much as you can and good luck. Agree with precisionworks, A good place to look is Accu Trak 

http://www.accu-trak.com/index.html

Good luck.


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## PCC (May 9, 2012)

I had a chance to look at the Accu-Trak site and the main thing that I got from it is that it is important to drive the knurl forming wheels into the piece hard and deep on the initial rotation to get it to start tracking right away. I was performing the knurling operation much like cutting threads: start lightly then feed in more to get it to where I want it to be and this is not the right way to go about it.


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## darkzero (May 10, 2012)

I also use the info from Accu-Trak for reference. You can also search for a calculator online or make your own with a simple excel sheet.


I also use their wheels. Full form Ti 6Al4V


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## precisionworks (May 10, 2012)

darkzero said:


> Full form Ti 6Al4V



That is just slightly beyond awesome 



> I also use the info from Accu-Trak for reference.


Good stuff on their site.

A few small details that help a lot:

1) Cut a 45° lead in chamfer at the starting end of the part. The knurling wheels have a similar chamfer & will start more easily than trying to ride over a 90° edge.

2) You cannot use too much lubricant. 

3) Slower speeds + faster feeds. Can't remember the numbers (they are in the file in the shop) but IIRC about 200 rpm & about .020" - .030" per rev. At the end of the pass hit the foot brake OR kill the power ... don't disengage the feed. 

4) Set up with material that's identical in diameter & composition. It kills me to set up on Ti-6-4 because the scrap cost is so high but there's no other way to get it right.


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## wquiles (May 10, 2012)

precisionworks said:


> That is just slightly beyond awesome


+1

Excellent work Will :bow:


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## PCC (May 10, 2012)

That is awe inspiring. Wow! Thanks!


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## StrikerDown (May 10, 2012)

Looks like somebody was paying attention when they taught knurling! 

Quite awesome Will!


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## cmacclel (May 10, 2012)

Will your the man! Knurling STINKS in my book. Seems no matter what I do repeatable results never happen. Are you using the convex wheels? My new Aloris Knurling tool came with the Accu-Trak wheels but the standard HSS ones.

Mac


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## darkzero (May 11, 2012)

precisionworks said:


> That is just slightly beyond awesome



Thank you everyone! 

That especially means a lot to me coming from all you well experienced guys. 





cmacclel said:


> Are you using the convex wheels?



From what I remember, you're the first that I recall to actually mention that here. Of all the knurling related threads I've read here on CPF, I'm surprised that there's not much talk of the wheels. Yes I am using the convex wheels & I believe that is the #1 reason why I have been successful. I've knurled aluminum & steel fine with just beveled edges. I have some straight edge wheels that I've only knurled aluminum with a bump knurler but would never try anything harder. And I've tried knurling Ti with beveled edges with results that I would never want to try again after using convex wheels for axial feeding.


I posted this pic a while back & asked if anyone could figure out what I was doing differently. No one guessed it & the post was lost in the crash. But here you can see the convex wheels. I'm also using carbide pins.






The very first time I tried knurling Ti I was a bit intimidated by everything I have read. I tightened up all the gibs & locked down everything, crosslide, compound slide, & the tool post.....






Believe it or not, my very first attempt on Ti was decent.











So then I wanted to find out for myself why full form Ti knurling was such a PITA. I quickly learned why & spent some time cussing at the Ti but then ended up with this:












Now I find that I don't need to lock down the cross slide or compound slide even with the compound set at an angle. I've never ever used the dowel pins for the tool post since. The tool post has never moved on me while knurling Ti.

I replaced the standard nut used for locking the adjusting nut on the scissor knurl with a lock nut. Makes set up time for different diameters longer but much more consistent for fine adjustments.







Now I won't use anything but cobalt Accu-Trak wheels. The wheels are important and calculating wheel pitch & work piece diameter is just as important. But from what I learned, even calculating pitch & diameters, I still have to test with slightly different diameters to get a very nice knurl depending on how full of a knurl I want.

On top of that, when I full form knurl Ti, as hard as it may seem, I try my best to get a full form in one pass. If I full form with multiple gradual passes I get flakes in the knurling which is very time consuming to clean up.







The photos from the other thread.












On my list of things to try is this small straddle knurler (Thanks to Barry for posting the deal) that I got to do thin bands of knurling (0.157" width wheels) on smaller diameters.











(Everything I've mentioned above is in regards to Ti, I don't play with anything else.)

:wave:


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## precisionworks (May 11, 2012)

> when I full form knurl Ti, as hard as it may seem, I try my best to get a full form in one pass.


+1

In form knurling the metal is displaced - some inward & some outward. Ti-6-4, like many stainless steels, is subject to work hardening & fewer ops give better results. The material is relatively soft as received, roughly 30 HRc, and knurls much like Type 304 stainless or 4140HT. Knurling & other forming ops can raise the Rockwell hardness by as much as 10 points. 

In Ti-6-4 less is better


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## cmacclel (May 11, 2012)

Will are you using the 21p wheels? I need to order a set and had it on the list months ago until I saw MSC wanted almost $40 each for the knurls  I picked up the Aloris BXA-19 knurler a few months back.

Mac


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## Anglepoise (May 11, 2012)

Very interesting info darkzero. I am using the Accu-Trak wheels, carbide pins, on a good scissor style tool, but my wheels are not convex and I have to pin the tool post or it will swing and my results are not consistent. I will try a set of convex wheels. Your results are fantastic. This is the one area in machining I dread and anything to make knurling a little less stressfull will be most welcome.
Thanks.


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## gt40 (May 12, 2012)

Really impressive! So what is the idea behind the convex wheels?


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## precisionworks (May 13, 2012)

gt40 said:


> Really impressive! So what is the idea behind the convex wheels?


Convex wheels have a number of advantages (for rolling convex work):

The elliptical shape provides a lead-in to the center of the roller & a lead-out after center - the wheels start more easily & track much better. It's harder (but not impossible) to double track with convex wheels.

Instead of uniform pressure across the roller there is maximum pressure only in the center of the roller. The pressure per unit measure is the same as with a flat wheel but the area of maximum pressure is much less. Said differently, the total knurling force is less & this gives longer tool life. Appearance is usually much better than with a flat knurl.

Great info from GenSwiss.


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## StrikerDown (May 13, 2012)

I have made a couple handles for home grown gun tools out of Delrin. Being a tad slippery when smooth it works well for knob type applications where you want or don't mind if it slips or rotates in the hand. For those applications where you want some grip I was wondering if Delrin can be knurled? Obviously Will Q can cut knurl but can it be knurled like Dark Will is doing here?


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## darkzero (May 13, 2012)

cmacclel said:


> Will are you using the 21p wheels? I need to order a set and had it on the list months ago until I saw MSC wanted almost $40 each for the knurls  I picked up the Aloris BXA-19 knurler a few months back.
> 
> Mac



Yes I used 21p wheels on those pictured. Forget MSC, I ordered directly from Accu-Trak for $26ea. Which reminds me, I need to order some different pitch wheels too.

I tried to get me an Aloris BXA-19 too but always missed out, then I scored the Eagle Rock for dirt cheap.


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## cmacclel (May 15, 2012)

darkzero said:


> Yes I used 21p wheels on those pictured. Forget MSC, I ordered directly from Accu-Trak for $26ea. Which reminds me, I need to order some different pitch wheels too.
> 
> I tried to get me an Aloris BXA-19 too but always missed out, then I scored the Eagle Rock for dirt cheap.




I'll be honest with you I don't really like the Aloris Knurler as it seems when I tighten up the wheels it binds which puts uneven pressure on the wheels. I find I need to tap the bottom of the tool with a rubber mallet while tightening the jaws or it seems the top wheel gets more pressure. The Aloris holder sure if beefy bit the self centering portion doesn't work that well.

I wish I saw the thread on the smal knurlers as I would really like one but Travers was sold out by the time I saw the thread Barry posted


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## Maglin (May 18, 2012)

I have used a very old and very dull knurling tool with great results. Turn the work at 1/4 speed of the cutting materials speed. If HSS wheels that would require 1000 rpm run at 250 rpm. Feed between .010-.020"/rev. I also start the first pass .025" in and the second pass .045" in. I usually get it finished in two passes. I always start with the knurler off the work piece and start the lathe. Advance until both wheels start to turn on the knurler and stop the lathe. Then advance another .025". Start the lathe and engauge the feed and put a decent amount of oil on the work. I disengauge the feed then turn the lathe off. If I see a double cut I turn it out and start over. Usually on the second go it's at the correct diameter and finish in 2 passes with a perfect knurl even with a dull tool that uses crossfeed pressure. It's not good on the spindle bearings but it does work great for me. People usually wonder how I make it look easy. I just read the machinery handbook and some forums and just go at it. I find .015"/rev feed to be very good for me. This is on straight turned material with no bevels. Also much past 500 rpm the oil starts to just fling everywhere so I don't knurl past that speed. I also use my grooving tool when I'm done to make grooves in my knurls to give them a better look and feel in the hand. I made two hammers recently in school and knurled both handles with their screw on bottoms on at the same time so the knurls on both would match. One came out perfect and people don't even know that the hammer has a hollow handle with a pocket inside. The other got a double knurl and I couldn't cut the double cut off the screw on bottom. Still looks good and people still don't realize that it's removable even though the knurls on the handle are good and the bottom is not.

P.S. DarkZero your lathe is always clean even on pics of stuff being worked on. I think mine would make you cringe. I clean my chips out but I don't wax my lathe or wipe it comepletly down like yours. We get humidity spikes here and I have to kept a thin coat of oil on mine. Excellent knurls btw.


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## DIWdiver (Jun 1, 2012)

I am definitely no expert on knurling, and am soaking up this info like a sponge. But I can definitely say getting the diameter right can help a lot. Not to say the "feed hard and fast" camp is wrong, but it's not always practical. 

I recently wanted to knurl part of a section with uniform diameter, so starting from the end with bevels and convex wheels was not an option. I'm also a cheap a__ so my tool is a Phase II, not sharp, 2 wheels in one block of steel, no great bearings, nightmare. Here's how I got some pretty good results despite my best efforts to prevent them:

1. Turn work to desired diameter, with a little extra, so I can remove (knurl pitch/3) from the diameter with no ill effects.
2. Advance the tool until one wheel starts to turn. If the other wheel isn't turning, adjust the tool (remember, I have two wheels in one block of steel).
3. Repeat step 2 until both wheels turn with minimal contact with the work.
4. Stop the spindle, advance the tool 0.002", and turn the spindle one turn by hand, plus just a little more.
5. Examine the part, which should have a set of very light lines on it. At the point where it overlaps, if the second set lines up pretty close to the first, great. Feed and go. If they don't line up well, take off some material. Removing 1/3 of the knurl pitch from the diameter (actually, it's 1/pi, or 1/3.1415927...), would get right back to the same condition. If the second set of lines is just behind the first set, then take off a small fraction of that amount. If it's just ahead of the first set, then take off most of that amount.

I've done only a handful of knurling jobs, but the last few, following this procedure, have produced satisfactory results. Nothing like Darkzero's, but at least I have something to aspire to!

Maybe the next step is to grow a pair and feed hard and fast, but only after following my procedure above!


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## precisionworks (Jun 21, 2012)

Spent half an hour on the phone with Kevin (knurling tech support) at Eagle Rock. Both my scissor tools are Eagle Rock & this seemed like the perfect time to get a pair of convex cobalt knurls plus a pair of solid carbide pins ... to make a titanium hammer handle 

The arbor press was used to push out the steel axles & they were a tight fit. Probably 5000# of pressure was needed to move the pins out. Pressing in the carbide pins will be easier. 

Plans are to make one pass with the heavy CNC scissor knurler (flat steel knurls) & take a photo. Then repeat the process on a fresh titanium bar using the convex cobalt knurls in the lighter duty knurler. Should be interesting.


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## precisionworks (Jun 23, 2012)

The starting diameter of the work is critical if perfect knurling is desired. Starting diameter is always smaller than nominal diameter because knurling causes the diameter to increase. The key number for knurling is Diametral Pitch & this can either be calculated or gotten from tech support at the company that makes your knurl wheels. Since all my knurls are 128 Dp a quick look in Machinery's handbooks gives these values:

Nominal D 
0.500" 
0.625" 
0.750" 
0.875" 
1.000" 

Corrected D
0.4972"
0.6215"
0.7458"
0.8701"
0.9944"

You can also use one of the many spreadsheets available like this one from Dorian: http://www.innovativetoolsales.com/dorian_knurling.htm


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## darkzero (Sep 11, 2012)

StrikerDown said:


> I was wondering if Delrin can be knurled? .....can it be knurled like Dark Will is doing here?



I guess it can....

I was knurling some Ti today & before I put the knurler away I decided to try. I didn't try a full knurl & ran it dry (something I've never done before :green with only blasting cold air. I have a feeling it will "melt" if I try a full knurl. I'll try the next time I use the knurler again.


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## wquiles (Sep 11, 2012)

Dude!

Your knurling is so freaking awesome :bow:

Will


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## precisionworks (Sep 11, 2012)

wquiles said:


> Your knurling is so freaking awesome ...


+1

The partial knurl is a nice solution for some jobs & it's much easier to do on Ti-6-4



> knurling some Ti today ... & ran it dry


Ouch 

Even with carbide pins & cobalt convex knurls the pressure at the pin-knurl contact is immense. That pressure generates heat that is hard to believe. If you feel you must run dry the max knurl speed drops in half.


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## StrikerDown (Sep 11, 2012)

PW, I think he ran it dry in delrin.

Thanks Will, The partial knurl looks great in delrin and I'm guessing it really adds to the traction, plain delrin can be a bit slippery.


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## darkzero (Sep 11, 2012)

Thanks everyone! 



precisionworks said:


> The partial knurl is a nice solution for some jobs & it's much easier to do on Ti-6-4



These are going to be handles, I initially intended on going with a full knurl but they were too coarse & harsh on the hands. I may try a finer full knurl next time.



StrikerDown said:


> PW, I think he ran it dry in delrin.
> 
> Thanks Will, The partial knurl looks great in delrin and I'm guessing it really adds to the traction, plain delrin can be a bit slippery.



Yup, that's correct, thanks Ray. 

I would say the partial knurl on the delrin is still slipppery but better than nothing. Grooves would probably work better or a slightly deeper knurl. A set of grooves would be easier & look good too.


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## Kestrel (Sep 11, 2012)

darkzero said:


>



I know I'm late to the party, but this is so incredibly beautiful that I just had to quote it again. :thumbsup:


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## darkzero (Sep 11, 2012)

Kestrel said:


> I know I'm late to the party, but this is so incredibly beautiful that I just had to quote it again. :thumbsup:



Thank you Sir!


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## darkzero (Sep 11, 2012)

darkzero said:


> I guess it can....
> 
> I have a feeling it will "melt" if I try a full knurl.



I guess it can...part 2.

Retracking knurling can be failry easy with only a bit of practice even on such a light knurl. I'm pretty good at retracking knurls but I didn't know what to expect on a soft non-metal material like delrin.

Here you can see I was able to retrack the shallow knurl with no problem but my attempt at a more full knurl wasn't successful. As I suspected it "melted". Again I ran it dry & there was "flaking" so to speak. This is similar and consistent when trying to full knurl harder metals with excessive passes as it overheats/work hardens.








So then I tried again but this time flooding the knurls with Boelube as I normally do. The result was much better & I think this is as close as I can get to a fully formed knurl on delrin. I doubt you could ever get crisp fully raised diamonds on delrin without using a cut knurler. Now I'm curious what knurling will look like with a cut knurler. I wonder if it's possible as heat is a major factor in the result. 

I think it's pretty good for a plastic & it has nice grip without being too coarse on the bare hands as if this were a metal due to the rounded off peaks. Didn't think it would be possible.


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## StrikerDown (Sep 11, 2012)

Will, That actually looks pretty cool.
I too wonder what cut knurling would look like, maybe Will Q... ;-)


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## darkzero (Oct 4, 2012)

Did some more Ti knurling today, but something a little different.....with a _twist_.


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## Th232 (Oct 4, 2012)

Now that's something I've never thought about, and it looks quite good!

Were there any issues with using only one wheel?


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## darkzero (Oct 4, 2012)

Th232 said:


> Now that's something I've never thought about, and it looks quite good!
> 
> Were there any issues with using only one wheel?



No issues, I still used two wheels since it's Ti.


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## wquiles (Oct 4, 2012)

darkzero said:


> No issues, I still used two wheels since it's Ti.



Will, that looks freaking AWESOME !!!


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## darkzero (Oct 4, 2012)

wquiles said:


> Will, that looks freaking AWESOME !!!



Thank you very much Will! :wave:


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## darkzero (Mar 17, 2013)

darkzero said:


> Did some more Ti knurling today, but something a little different.....with a _twist_.





I had one of these pieces just sitting around so I decided to make something for Matt (QMT) for hooking me up so much with stuff for the mill. But ssshhhh, he doesn't know yet, he should be getting it this Tues.

















Here's some other Ti ice picks that I made:














I made a couple pieces for Fred & I just noticed what he turned one of them into. That is awesome Fred, as always! :bow: :twothumbs
http://www.candlepowerforums.com/vb...P-Diagonally-Knurled-Ti-RCR123-with-McClickie


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## Toaster79 (Mar 17, 2013)

Stop it guys! Minors are attending here so no more machining porn please!


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## precisionworks (Mar 17, 2013)

Nice stuff Will 

If you have a flat diamond wheel (for sharpening TIG tungstens) it does a great job pointing small Ti rods. The wheels are on eBay all the time, never more than $50 for one made in USA. Mine is 11 years old & is just starting to wear out, probably need to replace it in a few years.

http://www.ebay.com/itm/2-x-1-x-1-2...060?pt=LH_DefaultDomain_0&hash=item257ad6ac14


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## darkzero (Mar 17, 2013)

precisionworks said:


> Nice stuff Will
> 
> If you have a flat diamond wheel (for sharpening TIG tungstens) it does a great job pointing small Ti rods. The wheels are on eBay all the time, never more than $50 for one made in USA. Mine is 11 years old & is just starting to wear out, probably need to replace it in a few years.
> 
> http://www.ebay.com/itm/2-x-1-x-1-2...060?pt=LH_DefaultDomain_0&hash=item257ad6ac14



Thanks Barry! Unfortunately no, I don't have one of my own but have always wanted one after using some. I thought they were way more expensive than that though.

I just machined the tips on these in the lathe, then carbidized the tips for better wear resistance.


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## PCC (Mar 17, 2013)

That's beautiful work and something to aspire to.


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## wquiles (Mar 17, 2013)

precisionworks said:


> Nice stuff Will


+1


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## precisionworks (Mar 17, 2013)

> I thought they were way more expensive than that though.









From my $50 wheel


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## PhotonFanatic (Mar 17, 2013)

Will,

Wow, I love those Ti ice picks--too bad I'm not a drinker, or I'd need one. :devil:

The alternation from shiny grooves to what looks like bead blasted grooves on the green ice pick is very slick. Were the non-shiny grooves bead blasted, etched, or??






And thanks for the kind words re the Indigo Flow, as I've named it. Of course, you get all the credit for making it possible with your outstanding knurling. :thumbsup:


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## darkzero (Mar 17, 2013)

precisionworks said:


> From my $50 wheel



Very nice. 

Do those diamond wheels need to run fast? Will they work ok on a common 6" buffer or bench grinder? Only time I used them were in shop class on the Baldor tool grinders grinding carbide bits. They seemed to spin so fast & quiet that one time someone had left it on & I had no idea it was running. I touched the wheel by accident & it felt like it was so fine that it really didn't do anything to my finger. But man did they grind tools nice. I took advantage & brought all my bits to class to touch them up. 

Here's another pic of the carbidized tips.










PhotonFanatic said:


> Will,
> 
> Wow, I love those Ti ice picks--too bad I'm not a drinker, or I'd need one. :devil:
> 
> ...



Haha, that's good to hear! 

Thank you very much Fred & there couldn't be a better name for that wonderful piece of art. Absolutely beautiful, thank you for sharing that link! I'm just honored to have been able to help in a small part in another one of your many fine masterpieces. 

Yes, etched, anodized, machined again, anodized again, then grooved again.














And one last simple addition for today. Someone had seen some begleri beads that I made previously for someone else & ordered a pair. I really have no idea what they are for (I suppose I should just search) but here's another version of them that I whipped up today.


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## precisionworks (Mar 17, 2013)

> Do those diamond wheels need to run fast? Will they work ok on a common 6" buffer or bench grinder?


Mine is mounted on a high dollar Ryobi bench grinder ($49 at the big box store a few years ago, might be $59 now). 3450 rpm is the speed of my grinder & the diamonds seems to cut better at faster surface speed. Titanium will spark hard so wear the same shade goggle you would for gas welding or cutting, maybe a #4. The heat transfers slowly with Ti so you'll probably get the point ground before it gets too hot to hold.


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## darkzero (Mar 17, 2013)

Ok, another one to add to the buy list, thanks. I've got a Craftsman bench grinder that doesn't see much use. Have other things in mind for this wheel though, I hate grinding Ti, luckily I don't have a need to very often.


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## precisionworks (Mar 18, 2013)

The wheel I have (shown above) is meant for a surface grinder & has a 1.25" bore. Made an adapter from aluminum rod stock & it runs without vibration. Most diamond wheels are side grinders like this one.

Sometimes you can find a SG wheel for less money, sometimes not, but the adapter is dead simple to make if you get a good buy on a SG wheel.


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## darkzero (Mar 19, 2013)

> Stub is on the left–inside the collet. The head is now separated from the stub and has been ‘caught’ by a bar inserted into the head. No need to ding the piece by letting it hit the lathe!



I like that! 

Fred, I love your WIP pictorials! I really should visit your site more often!


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## precisionworks (Mar 20, 2013)

> Stub is on the left–inside the *collet*.



OT but worth discussing IMO is the use of collets for flashlight work. They are without a doubt the #1 choice for machining small diameter bar stock or tube stock. Contact with the work is almost 100% whether using a collet that grips the OD (as shown in Fred's image) or whether the collet expands into the ID. Concentricity on a decent collet chuck will run close to dead nuts (Set-Tru type) while cost is less than half a 3-jaw or 6-jaw Set-Tru. 

Those should be reason enough to use collets but the last feature is the big bonus ... safety. The collet chuck nose is smooth:






This allows keeping my hand near (& sometimes resting on) the spinning chuck. Try that with a 3-jaw or 6-jaw but call the hospital first to tell them to reserve a room :devil:

All the shops that do machine work for me (should say all six shops) run collets for their small work. Jawed chucks like the Set-Tru are very nice when working diameters too large for a collet. They are unkind to body parts, will beat tooling to death if the jaws meet an insert, and will catch long hair/shirt sleeves/almost anything. 

For flashlight work the collet chuck stays on my lathe. It also works well for quite a few gunsmithing ops. The 3-jaw Bison Set-Tru is used when a bunch of parts need to be run & they are too large to fit into a collet. 

Rant over


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## PhotonFanatic (Mar 20, 2013)

Thanks, Will. Of course, we know from whom I learned that trick for catching parted off pieces, right? 

I still just grab most of them with my fingers, but sometimes you need to pay more attention to the parting off operation than to catching the part.

Barry -- I agree 100% with the use of collets to hold flashlight parts--10X safer than the four-jaw chuck.

Did you notice my little cheat, when the part is 20.20mm, say, and you only have a 20mm or a 20.5mm collet to hold the piece? Yup, wrap the piece in a sheet of aluminum cut from a beer can, or a soda can, if you are a teetotaler. :devil:

That's also something I do in the four-jaw chuck when I have a nice surface already, and that I want to keep that way. Only care to take is that you only want to be doing light cuts, otherwise the piece can rotate easily in the aluminum wrapper.


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## darkzero (Mar 20, 2013)

I hear ya & is partly what led me to it. Not always easy to catch a part when needed in certain situations.


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## precisionworks (Mar 22, 2013)

> I agree 100% with the use of collets to hold flashlight parts--10X safer than the four-jaw chuck.



One of my friends on the gunsmithing forum at PM recommends the ER-32 or ER-40 for barrel work on the lathe ... so I ordered a back plate to fit my spindle & an ER-32 fixture plate. Already have a full set of ER-40 but the fixture plate is OOS until June 

Will be interesting to see how the ER compares to the 5C but one thing is certain ... cost is low. About $160 for the back plate & the fixture plate.


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## precisionworks (Apr 22, 2013)

Image of Schedule 80 3/4" aluminum pipe. 1.050" OD & .742" ID so just about perfect for someone who wants to build a body to run 18650's.

Started with about 8" stuck out of the 5C collet & knurled a 6" section. Moved down the pipe & knurled the other two areas. 











Came out OK considering the pipe was not OD turned before knurling, ran the tool on the mill finish OD. About 250 rpm, fastest feed in the gearbox, convex knurl wheels with TapMagic flowed onto the wheels during the forming.


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## wquiles (Apr 22, 2013)

Very cool!


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## precisionworks (Apr 23, 2013)

Thanks Will 

I carry that every morning during my fast walk (4 miles in one hour, sometimes a bit more). A bluetooth HR strap transmits to the iPhone5 & the MapMyHike app calls out time/speed/distance/heart rate every 0.1 mile. I go as hard as possible & often don't see aggressive dogs until they are close ... but they certainly recognize the aluminum stick when it's raised into the batter up position :devil:

Haven't had to tap one yet. Almost did some body work on a Lincoln Town Car driven by a fossil aged lady who was either texting or combing her pretty blue hair.


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## darkzero (Apr 23, 2013)

wquiles said:


> Very cool!


+1

Cool walking stick!


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## precisionworks (Apr 24, 2013)

Thanks Will 

A lot of email comes in asking me to do jobs that are _simple, easy, & should not cost much _:devil: So here's an idea for those of you wanting a quickie project ...

ID is 0.742" & that means most 18650's will drop right in (need to ream to 0.744" to get the fatfat Panasonic cells to work). You can probably see where this is headed. The tube-walking stick will hold 13x18650 & _all you need to do _is machine up a tail cap (preferably Ti-6-4, loaded with trits, etc.) & design a head that runs on 56 volts. No hill for a climber, just run 20 XM-L's ... sucker ought to be bright at 14,000 lumens. Mag ring variable output would be a nice touch & again this has been done before so it will not take much effort to add the feature. Sprinkle a few trits in the head for bling. 

Keep the cost down, something under $100, and watch your product fly off the shelves. Please cut me in for 66% of all profits since I did all the hard work for you :nana:

Expecting to see prototypes tomorrow or the day after ...


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## wquiles (May 31, 2013)

OK, with much advice/support/tips from the "good" Will, here is "evil" Will with some initial tries at Knurling Titanium.

Now, being that I am not all that smart, instead of starting with steel, or with CP2 (Grade 2), I am stuborn enough of trying this on 6al-4v.

I am using my Dorian cut knurler, and using Will's calculator for setting up the diameter based on the knurler at hand:

PM12x36 lathe
Dorian Cut knurler, with RS 25 wheels
Ti Bar Dia = 0.650"
Carriage speed = 0.012 IPR
Spindle Speed = 65 RPM
Infeed = 0.018" (all in one pass)


Getting the diameter set (per Will's calculator):







Cutting a 60 deg area to help ease/start the knurlers:






Setup for my PM12x36 (back gears were left as when I cut 20TPI threads, but the front dials were adjusted to 0.012 IPR as shown in these pictures):











Starting to "cut" threads, various angles (you know me, I can't help but take lots of pictures!):
















Infeed:






And yes, we are most definitely cutting metal away:






After a single pass. Obviously not great, but not too bad as a starting point:






Here in the cropped picture you can see that the grooves being cut are not quite "even", and that there is also some metal being displaced as well - note this is "as is" - I have not cleaned the piece):







Short movie:
You Tube Movie


Will


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## darkzero (May 31, 2013)

Great start on Ti Will! I'm sure you will get it in no time. Looks like it's tracking pretty well. I wonder how cut knurling looks when double tracking? Sometimes I actually double track intentionally to get a finer knurl from a set of knurls but it's very tricky to do so.

I'm really anxious to see when you get a good knurl, been real curious to see how crisp & clean cut knurlers can produce knurls. Well I'm pretty sure I have seen some but I want to be sure. Damn I want one of those Dorian cut knurlers!

Looking at your pics, it seems that cut knurlers are designed to knurl in only one pass & can't be traversed in reverse for an additional pass. I can retrack pretty easily after removing the knurler from the work piece, I wonder if cut knurlers can be retracked fairly easy as well? If yes then you could make more passes over that test piece you have.


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## precisionworks (Jun 1, 2013)

> Carriage speed = 0.012 IPR


Some good info here from Dorian. Sounds to me like the carriage speed is about half of the recommended number & that usually causes double tracking (too much dwell time in the same spot).

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CG4QFjAH&url=http%3A%2F%2Figor.chudov.com%2Fmanuals%2FKnurling-Manual.pdf&ei=4fmpUcntM4_i8gTN7IDgAw&usg=AFQjCNFJ1e6aYBevuNJWfGFatAbbcEAruQ&sig2=73u3hJp5MRcGcEYrKXMHOw&bvm=bv.47244034,d.eWU


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## wquiles (Jun 1, 2013)

darkzero said:


> Looking at your pics, it seems that cut knurlers are designed to knurl in only one pass & can't be traversed in reverse for an additional pass. I can retrack pretty easily after removing the knurler from the work piece, I wonder if cut knurlers can be retracked fairly easy as well? If yes then you could make more passes over that test piece you have.



That is one of the things I have not quite understood yet - can I do more than one pass?

I guess I would have to retract the tool, run the lathe in reverse (while keeping everything engaged, carriage-wise), then do another deeper pass?




precisionworks said:


> Some good info here from Dorian. Sounds to me like the carriage speed is about half of the recommended number & that usually causes double tracking (too much dwell time in the same spot).
> 
> http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=8&ved=0CG4QFjAH&url=http%3A%2F%2Figor.chudov.com%2Fmanuals%2FKnurling-Manual.pdf&ei=4fmpUcntM4_i8gTN7IDgAw&usg=AFQjCNFJ1e6aYBevuNJWfGFatAbbcEAruQ&sig2=73u3hJp5MRcGcEYrKXMHOw&bvm=bv.47244034,d.eWU




Do you mean this table:






How/where are you reading the table to come up with the recommended carriage speed? I am not sure I am following what you are telling me 


Will


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## precisionworks (Jun 1, 2013)

wquiles said:


> Do you mean this table:



From GenSwiss:

END-FEED KNURLING from the turret (axial feeding only) is usually done at .005/.030"/rev (.1-.7 mm/rev), using the slower range for coarser Knurling on high-alloy steels, faster for finer pitches and on brass, aluminum or mild alloy steels. Normally the dies are fed off the work about twice as fast. Upper table applies only with a turret-type lathe (CNC or manual) where the tailstock feeds in. 

The numbers in the lower table show 22 for alloy steel with a 16-20 pitch knurl. Your speed is 12, about half what the table calls out.


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## wquiles (Jun 1, 2013)

precisionworks said:


> From GenSwiss:
> 
> END-FEED KNURLING from the turret (axial feeding only) is usually done at .005/.030"/rev (.1-.7 mm/rev), using the slower range for coarser Knurling on high-alloy steels, faster for finer pitches and on brass, aluminum or mild alloy steels. Normally the dies are fed off the work about twice as fast. Upper table applies only with a turret-type lathe (CNC or manual) where the tailstock feeds in.
> 
> The numbers in the lower table show 22 for alloy steel with a 16-20 pitch knurl. Your speed is 12, about half what the table calls out.



That does not "sound right". Any table that is suggesting that I go faster with allow steels and slower with aluminum sounds suspicious to me. Here are the instructions that came with my Dorian knurler - if anything, I might still be going a tad too fast for the diameter of this piece:
(sorry it is a rather big file)
http://m3coupe.com/Titanium/Dorian_CNC_Modular_Cut_Knurler.pdf


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## wquiles (Jun 1, 2013)

Looking on my good Belomo 10x Triplet, I noticed that the tips on one of the cut knurlers were worn, so I swapped them both to the new/un-used side. I then proceed to try two new experiments:
1) I decided to try to cut the knurls in 3 passes: 0.008", 0.018", and 0.020" (last one being more of a "clean-up" pass):
Here I am making the first pass:
















Second pass:






The actual cutter I am using (remember the home-made 1" BXA tool holder?):






After the last pass:






2) I also wanted to try creating the swirl knurling, using only one wheel - two passes (0.010" and 0.020"):
















Final product (far right was my original knurling - done in one pass):






Close-up of the spiral - not good. It is sharp and ragged. In one direction is smooth, in the other direction it "grabs" your skin!:






Close-up of the cur knurl done in 3x passes - much, much better. I would have to go deeper (more infeed) to get the pointy tips on the piramids, but this is actually very nice looking for me as a newbie:






Kudos again to the "good" Will for tips/advice to get me this far - much appretiated bud :bow:

Will


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## Energie (Jun 2, 2013)

*Homemade knurling tool:*





















*Sharp edges:*

















*Short clip:*
http://www.youtube.com/watch?v=uoECE9ORO_A
(You can hear, when the start-track ist ready)


*Finished part, shown in the clip:*


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## wquiles (Jun 2, 2013)

Beautiful cut knurling - nice job!


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## precisionworks (Jun 2, 2013)

Energie said:


> *Finished part, shown in the clip:*



That does a great job


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## I'mGatMan! (Jun 4, 2013)

Fantastic to see you attempting this, Will. You know I'm excited!


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## darkzero (Jun 4, 2013)

wquiles said:


> Kudos again to the "good" Will for tips/advice to get me this far - much appretiated bud :bow:
> 
> Will



No problemo Will, glad I could help! 





precisionworks said:


> That does a great job



+1

Very nice!



>


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## wquiles (Jun 12, 2013)

I have not posted in a little while, since I am setting up flood coolant in my lathe. Yes, I know, I though I would never do it, but the more I work with Titanium the more it seems I need flood coolant for some operations. Barry of course is helping me on the upgrade. Once I get things setup I will continue with my knurling experiments


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## darkzero (Jun 18, 2013)

This is the longest I have ever knurled Ti continuously, it was quite interesting, & luckily it came out great. I hope I don't have to do that again anytime soon!










What was it for? I was asked to make a Ti spear, he had only 3 criteria, 30" long, knurled, & sharp as hell! As always he trusted me with the rest. I decided the sharp as possible part wasn't the best idea so I went with carbidized micro beveled tips. So here it is, with a _"twist". _The _Ti Zombie Killer, _31.75" OAL, 5/8"Ø, & 2 spears for the price of one.


(Sorry for the crappy pics)


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## wquiles (Jun 19, 2013)

That looks totally wicked :thumbsup:


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## PhotonFanatic (Jun 19, 2013)

wquiles said:


> That looks totally wicked :thumbsup:



And freaking dangerous. Yikes!


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## vestureofblood (Jun 19, 2013)

"good" Will, "evil" Will, whoever, thanks for sharing. I learn so much from your posts. I can barely get a decent knurl on easily machinable metals. That looks so good. I may have to try doing that multi pass thing, I never imagined that would help. That "cut" knurler is a new one on me too. I had never heard of such a thing.


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## wquiles (Jun 21, 2013)

Now that I have the flood coolant running, I tried again the cut knurler - much, much better. Here on the left I am setting up the OD (Will's calculator) - the portion on the right was the one I did last time which came out OK:






Just two passes, one at 0.008" and the second (a cleaning pass) at 0.010":






The finish was even better (new on the left, and previous on the right):











The knurling came out nice enough that I decided to go ahead and make a DE handle out of this portion, so I am cutting of the previous piece, then cleaned it up:











Not too bad for a newbie:











Not that anyone would shave with it, but it looks cool:






Here I started drilling and tapping the new DE handle:







Will


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## wquiles (Jun 23, 2013)

A few more work-in-progress pictures. I first tried cutting the cone from the back, but did not have enough clearance:











So I changed it to the other side:
















Perfect fit:






Then I applied my preferred grooves, although I came with a slightly different pattern for this handle (2.6" long):






Cut and face the back:






Finished Ti DE handle:


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## wquiles (Jun 30, 2013)

I had a little bit of chatter on the groves near the tip, but otherwise this second piece turned up OK. Here the before and after on an EJ 89:













And check out the setting I used in the lathe (in order to get clearance) to cut that cone on the tip:











Will


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## wquiles (Jul 10, 2013)

The knurling wheels in my Dorian cut knurler are getting a workout as I fine-tune what works and not, so they are getting more wear than normal, most specially since I am experimenting on Titanium. The Dorian instructions that came with the knurler mention that the knurling wheels can be grinded in order for them to be used again:






Thanks to a recommendation from Barry a long time ago, I did purchase a Diamond grinding wheel for my bench grinder, so what I needed was a way to hold the wheel in order to grind the edges. So I made a tool from scratch 

Of course I started by knurling the end since I needed a way to rotate the insert against the grinding wheel:











On the other end, I made a very light press fit (no perceptible gap, but still comes in/out without much effort) to hold the wheel in place, while only exposing the very edge that needs grinding:






Here is the knurled end:






Here is the end that holds the wheel to be grinded (not super easy to tell, but the very edges on that wheel are a little worn - so this is the "before" picture):






The shop made tool:






I used a strong magnet to hold the tool at 90 deg to the grinding wheel, and the extra piece below (which happens to be Grade 2 Ti) raises the wheel just enough to make things work:






By the way, this is how it looks like with that LED shop light I finished a short while ago - notice the awesome and even coverage with zero harshness:






Here is how the wheels look after the light grinding operation:











And in between two not-yet-ground wheels:






And how do the wheels work after grinding - pretty good. This was on 6061 Al, after a single, light [0.006"] pass:






Will


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## wquiles (Aug 17, 2013)

Knurling free machining 360 brass (.7385" OD, 180 spindle rpms):


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## PCC (Aug 21, 2013)

Fantastic work as usual, Will!


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## wquiles (Aug 24, 2013)

PCC said:


> Fantastic work as usual, Will!



Thanks man. Will was very helpful in getting me started, so I owe to him the little that I know


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## wquiles (Sep 2, 2013)

With advice from Will, I tried the swirl knurling again today. As Will taught me, you still setup the OD appropriately based on the wheels (mine are 25 tpi), and then basically adjust the knurler so that only one wheel makes contact:
















Still need more practice, but making progress 

Thanks Will :thumbsup:


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## darkzero (Sep 3, 2013)

Awesome Will, everything looking good! :twothumbs


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## wquiles (Sep 4, 2013)

darkzero said:


> Awesome Will, everything looking good! :twothumbs



Thanks Will 

Here is my second try: A combo of traditional knurling and Swirl/Twist knurling:


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## wquiles (Sep 15, 2013)

"Normal" swirl knurl and very light swirl knurl, on free machining brass:






Closeup on my hand:


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## gadget_lover (Sep 15, 2013)

That is absolutely beautify work. You have a nice artistic touch to go with the machinist skills.

Daniel


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## wquiles (Sep 16, 2013)

Thanks much Daniel


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## wquiles (Dec 8, 2013)

Light swirl knurling with grooves on Titanium:


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## wquiles (Feb 22, 2014)

Just finished another Ti DE handle today. I opted for a "light" knurl instead of the deep knurling I have used before. Using my Dorian knurler:






Set the coolant very heavy):












And after a long while (knurling is very slow), the light knurling is done:












and ready to ship to its new owner:


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## wquiles (Mar 2, 2014)

Swirl knurling on Titanium (approx. 16mm OD):


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## wquiles (Jul 12, 2014)

Latest combo: diamond knurling and swirl (or twist) knurling:


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## precisionworks (Jul 14, 2014)

Brother, I remember when you were hesitant to machine titanium & it doesn't seem like that long ago. Now you & California Will are masters of Ti knurling. Impressive work.


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## MRsDNF (Jul 14, 2014)

That is some sweet knurling. The swirl in the pics for some reason is hard to look at. Love your work.


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## wquiles (Jul 14, 2014)

Thank you guys 

Yes, it is very difficult to photograph that swirl/twist knurling, even though this is not polished. This is "as machined", with a very light pass of wet 600 grit sandpaper over the 3 knurled areas to remove any tiny debris or surface imperfections (almost not needed at all).


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## vestureofblood (Jul 26, 2014)

Hey friends. 

I seem to have run into a new problem with this. The cheap knurler that came with my tool set has a pair of stationary wheel to knurl with. I never have had any luck getting both wheels to run a smooth pattern together because of issues with even pressure on both and worse one of the wheels had a bit of an oblong shape right from the factory. 

The way I always solved this was just by running a single wheel at a time, making 2 passes. Most often I'd get a good knurl this way. 

The other day I was striping some tail caps and all of a sudden I was not able to get an even pattern, even doing one wheel at a time. I figured the warp in the one wheel had finally got so bad that it just wasnt going to work anymore. So I ordered a new knurler ( a scissor type).

Anyway it came and the wheels on this one are round, but I still only get an even knurl at random times. I measured the space between the knurl teeth as best I could and turned the part to an even multiple of .046 and then tried it with one wheel pressed against the piece. This got me close so I took off a couple more thou and then the single wheel with light pressure tracked evenly. 

I proceeded to run the machine with both wheels clamped down on it and one wheel leaves a perfect pattern, while the other double tracks.:mecry:. EDIT: I also later tried using .0476 as the multiply number when I found that the medium set of wheels I have is 21 teeth per inch by googling the PN: 404-9294 of the knurler.

I have double checked the wheels and they are the same size/ spacing. The wheels are clean, and I have tried with oil and without. Every once in while I can get lucky and they will run a nice pattern, just not very often. Even running the wheels separately I get the same crap.

I really have no clue what I could possibly be doing wrong. Any suggestions are appreciated.


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## wquiles (Jul 26, 2014)

4 possible things to check:

1) For the knurling pattern to line up properly, the diameter of the work piece needs to be an exact multiple of the TPI of the actual knurling wheel being used. Are you checking the diameter of the part being knurled before you start knurling?

As an example, my Dorian cut knurler has 25 TPI knurling wheels. I use a calculator where I feed the initial diameter, this 25 TPI value, and it tells me what is the very next smaller diameter that will match these TPI knurling wheel. After doing it so many times, I actually have a 4x6 index card with like 20-30 diameters (larger to smaller) that I know match my particular knurler/wheels:







2) For the pattern to be even, both knurling wheels have to be exactly at the same ratio above/below the centerline. Here you can see an adjustment in my Dorian knurler ("D" is for down, and "U" is for up), so that I can fine-tune both wheels touching the work at the same time as the part rotates:







3) the diameter of the piece being knurled has to be consistent through the area being knurled. Any diameter change will affect the quality of the knurl



4) There can't be any taper in the area being knurled, otherwise the quality of the knurl will be affected. A taper will have the same effect as the diameter changing over the length of the area being knurled.



Knurling is not difficult, but it has to be nearly spot-on perfect for the knurl to come out great.


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## vestureofblood (Jul 26, 2014)

wquiles said:


> 4 possible things to check:
> 
> 1) For the knurling patter to line up properly, the diameter of the work piece needs to be an exact multiple of the TPI of the actual knurling wheel being used. Are you checking the diameter of the part being knurled before you start knurling?



I *THINK* I am doing this correctly. My wheels are 21TPI. So 1.000/21= .0476 Then .0476 x 35= 1.666 is my word piece diameter correct (or any multiple of .0476)?? I do measure the part after turning it.

My new knurler is a scissor type so even pressure is no problem. The issue I am having is that the top wheel will mark the correct pattern, ie it tracks even once I get the diameter of the piece correct, but the bottom one rarely does. I got it to work correctly one time ( thus the reason I suspect me as the problem). 

I said earlier that the wheels are the same size, because visually they match and a caliper measurement visually looked about the same between the teeth. However just now I measured the diameter of the wheels and consistently they measure a difference of .006 in size. Is it possible that my brand new knurler is crap? Is this maybe what is causing my problem.. How close in diameter are a good set of wheels??


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## darkzero (Jul 26, 2014)

vestureofblood said:


> I *THINK* I am doing this correctly. My wheels are 21TPI. So 1.000/21= .0476 Then .0476 x 35= 1.666 is my word piece diameter correct (or any multiple of .0476)?? I do measure the part after turning it.
> 
> My new knurler is a scissor type so even pressure is no problem. The issue I am having is that the top wheel will mark the correct pattern, ie it tracks even once I get the diameter of the piece correct, but the bottom one rarely does. I got it to work correctly one time ( thus the reason I suspect me as the problem).
> 
> I said earlier that the wheels are the same size, because visually they match and a caliper measurement visually looked about the same between the teeth. However just now I measured the diameter of the wheels and consistently they measure a difference of .006 in size. Is it possible that my brand new knurler is crap? Is this maybe what is causing my problem.. How close in diameter are a good set of wheels??



What is your starting workpiece diameter?

All my knurling wheels measure within .0010"-.0015" of each other.


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## precisionworks (Jul 27, 2014)

vestureofblood said:


> I have tried with oil and without.


There's an old song that goes something like:

You don't tug on Superman's cape 
You don't spit into the wind 
You don't pull the mask off The Lone Ranger 
And you never never never knurl dry 
My knurling tools all came from Eagle Rock USA. Discussions with tech support indicate it's impossible to use too much lubricant because of the extreme pressures involved at the knurl wheel axles. They recommend carbide pins, convex knurl wheels, lots of lube & slow SFPM.



> My new knurler is a scissor type so even pressure is no problem.


IMHO the scissor tool is tough to set up ... and that's the type of tool I also use. The major issue with the scissor is that the vertical axis knurl wheel center-line SHOULD be co-planar with the center-line of the part being knurled (plain English = the knurler must be centered over the part). How-sum-ever it's physically impossible to make that happen if there is any play or backlash in the cross slide. My knurler can be almost on center but as soon as the wheels are moved to exact part center the cross slide (& knurler) jump past center until the cross slide back lash is taken up.



> I measured the diameter of the wheels and consistently they measure a difference of .006 in size. Is it possible that my brand new knurler is crap? Is this maybe what is causing my problem..


Will & Will are the SME's on knurling so take this FWIW ... wheels need to be nearly identical in every dimension (major OD, minor OD, pin hole ID, pitch angle, depth of V-cut in wheel, etc.) & pins must have the same fit to each wheel or the tool will never form tracks that coincide. IMHO the greatest contributor to the high cost of precision knurling tools is that allowable tolerances are awfully close to zero followed by more zeros. 

YMMV.


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## vestureofblood (Jul 27, 2014)

darkzero said:


> What is your starting workpiece diameter?
> 
> .



IIRC a few were 1.69" and some were 1.304"





precisionworks said:


> IMHO the scissor tool is tough to set up ... and that's the type of tool I also use. The major issue with the scissor is that the vertical axis knurl wheel center-line SHOULD be co-planar with the center-line of the part being knurled (plain English = the knurler must be centered over the part). How-sum-ever it's physically impossible to make that happen if there is any play or backlash in the cross slide. My knurler can be almost on center but as soon as the wheels are moved to exact part center the cross slide (& knurler) jump past center until the cross slide back lash is taken up.



I have been toying with this. In most cases the way this particular one sets its impossible to get the axis exactly vertical. It appears visually like the bottom leg is longer than the top one, and there is not enough height adjustment to get them to the exact vertical position. 


Here is a shining example of the trash I repeatedly get using any of the 3 sets of wheels, at any height on about any size material. 






As you can see the wheel from the top roller tracks exactly the way it is suppose to while the delinquent lower one just craps up the whole piece.

Every once in a while I will get lucky and they will both track about the same, but if I'm being honest lucky is really all I'm getting. 99% of the time the top wheel is all I get.


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## darkzero (Jul 27, 2014)

precisionworks said:


> Will & Will are the SME's on knurling so take this FWIW



Thanks Barry but SME, nope not me. I'm just a student.




vestureofblood said:


> IIRC a few were 1.69" and some were 1.304"



Not sure how you are calculating starting diameters but for 21 tpi wheels you should be at 1.698 or 1.682. 1.304 is a good dia for 21 tpi. 

You can find various ways on how to calculate sttarting diameters, I just use a calculator cause it's easy & quick, no thinking involved. Here's one. Plenty of others out there too.

It's not always easy/possible to hit your mark on the thou or ten thou. Better to be over your mark then under, under is more prone to double track. Not as important on softer materials, deeper/full form knurls & coarser pitches. Shoot for a thou or 2 over you targeted diameter. Or if you will still be trying with the wheels that have a diff or 6 thou, try 3-4 thou over your targeted diameter & more initial feed if you are still having issues.


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## wquiles (Jul 27, 2014)

darkzero said:


> Thanks Barry but SME, nope not me. I'm just a student.


+1

Still much more to learn


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## vestureofblood (Jul 30, 2014)

*Problem solved!*


After several hours of frustration I finally found a solution that works.



*Step 1: *Place scissor knurler in appropriate bin.








*Step 2:* Drill out and replace worn out wheel studs in old knurler.




*Step 3:* Knurl as before.














*I very greatly appreciate everyone who commented*. To be honest I still dont know if the problem is my lack of experience or if that knurler is just no good ( not rigid enough maybe). I will probly give it another shot, but I really needed to get some work done so this was the best solution for the moment.


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## tino_ale (Dec 2, 2014)

Hi guys,

I got a cheap knurler off eBay, a cissor type that is a major POS. The thing will not keep the knurling wheels in line, they quickly end up crooked and they start pushing the carriage to one or the other direction, tearing the material in the mean time. Quite a disaster unless doing shallow knurling on soft material and on a narrow section (=I can't traverse). Does well on a narrow brass section for example.

So. That knurler was just a try. Now I want the real deal.

What I have noted that is proven to work even on the king of metals (titanium ) :
- acca-track cobalt convex wheels
- solid carbide pins
- Eagle Rock K1-44 HD cissor knurler
- knurl in a single pass, even full knurls, and use lots of lube or coolant

Accu-trak also makes heavy duty scissor knurlers, which is better ?
Any recommendation welcome as to wich knurler to buy.

BTW, do form wheels wear fast in general ?


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## precisionworks (Dec 3, 2014)

My first "good" knurl tool was the standard K1-201 & it did a nice job - now it sits in a drawer since I got the heavy duty K1-44. I also use the convex cobalt wheels & carbide pins. Both models are excellent tools but the K1-44 is more excellent. 



> use lots of lube or coolant


That's so important. You cannot apply too much & flood is best but I don't have flood set up on my lathe. I pump a constant stream of Rapid Tap on the upper wheel as it traverses the part.



> Accu-trak also makes heavy duty scissor knurlers, which is better?


No experience with that brand.



> BTW, do form wheels wear fast in general ?


The manufacturer can probably answer that but it depends on how many hours per day the tool is run.


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## tino_ale (Dec 3, 2014)

Thanks for the input.

I'm using a BXA Dorian QCTP on a PM1236 lathe. The "normal" shank size is 5/8", but since my holders will take up to 1" shanks, should I consider getting the biggest shank that will fit in the holder ?

In theory I guess so, especially since cissor type knurler can accomodate a height offset. BUT, I'm also thinking that the height adjustment may not be critical but still needed. If the height of the cissor is too far off, I can see how there will be a twisting action taking place on the shank.

Will I benefit from a 3/4" or even 1" shank on a cissor knurler or should I stick with 5/8" ?

edit :
OK now I'm confused ! There's not just the shank size, there is also the RH vs. LH vs. center round choice to make!


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## wquiles (Dec 3, 2014)

precisionworks said:


> That's so important. You cannot apply too much & flood is best but I don't have flood set up on my lathe. I pump a constant stream of Rapid Tap on the upper wheel as it traverses the part.


+1

At least for a cut knurler like mine this is of HUGE importance to have flood in this operation, as it will greatly extend the life of the knurler, and improve the quality of the knurl by removing debris as you go.


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## darkzero (Dec 3, 2014)

tino_ale said:


> Accu-trak also makes heavy duty scissor knurlers, which is better ?



I have no experience with the Accu-Trak knurlers either but I did have my eye on their heavy duty straddle knurler before I got my Eagle Rock, looks nice. 



tino_ale said:


> BTW, do form wheels wear fast in general ?



That's hard to answer, you'll need to ask the wheel manufacturers. It really depends on how much you use them, what materials you use them on, & if you are using the correct type wheels for the type of knurling you're trying to achieve. 

I only use Accu-Trak wheels & I have wore out one set of wheels using them strictly on Ti. Their current coating (gray, TiAlN I think) last much longer then their older coating (gold, TiN I think), at least for me anyway. Use them on only softer metals & they're probably last for years.



tino_ale said:


> Will I benefit from a 3/4" or even 1" shank on a cissor knurler or should I stick with 5/8" ?



My K1-44 is 3/4" shank but not by choice. You know how expensive the K1-44s are. Well I got mine for $80, practically brand new. Seller did not know what he had, lucky for me. Won't hurt to get a 3/4" shank if you don't mind paying the higher price, but it will stick out more for you.....

In general, I for one am not a believer in oversized shank tools. IMO an oversized shank (for your lathe size) is not going to make a noticeable difference in rigidity (like for BXA, going from 5/8" to 3/4"), well that is unless you like to hange your tools far out of the holder or the shank of the tool is not hardened. The only advantage I see in using 3/4" is the price, more deals to be found on larger tooling. But price is dependent on whether you have the oversized holders already or not as they cost more. In your case you already have them.

Dorian is all screwy with their tool holders, they can't seem to make up their minds & are always changing them. Since you have BXA as do I, lets talk about the Dorian 1" capacity holders which seem to be their "standard" now. 5/8" for BXA was the max standard set by Aloris. 3/4" for oversized holders. Dorian did this too, then they started supplying 3/4" as standard & now 1".

Just because your holders will accept 1" shanks doesn't always mean you can use them. Dorian used to make standard & oversized holders. Their oversized holders seemed to be discontinued now because as said they "standard" now. But the previous oversized 1" holder is not the same as the "standard 1" holder.



darkzero said:


> Here's a D30BXA-1 (standard holder p/n) next to a D30BXA-1-100 (oversized holder p/n). Looks the same right? They aren't, look at the set screws placement.
> 
> 
> 
> ...



With a scissor knurler, being off centerline height is more forgiving but having it way off centerline can add more stress to the scissor tool. Trying to reduce those forces as much as possible is best for knurling. I personally would not go with a 1" shank.



tino_ale said:


> OK now I'm confused ! There's not just the shank size, there is also the RH vs. LH vs. center round choice to make!



The regular K1-201 is still a great knurler. But if you _need_ the heavy duty version then go for it. Biggest different is mass, stronger shank mounting, & the ease of changing pins on the K1-44. Center is stronger but you can't knurl close up to a shoulder. That's what the LH & RH versions are for. But the shoulder version use different mounting for the wheels, not sure if they are available in solid carbide or not. The center (like I have) uses a straight pin. Carbide pins are essential for heavy duty knurling. I get my carbide pins from Accu-Trak also.


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## tino_ale (Dec 3, 2014)

From what I understand from the K1-44 info page :
- Knurl type column :
"form" is captive and rolling on a pin, won't knurl right to an shoulder even if RH or LH because the knurls are not on the edge of the scissors.
"form counterbore" is rolling on a screw type assembly and hanging on the side of the scissor tool, so could knurl right to a shoulder
As I don't think I'll ever want to knurl right to a shoulder, the "form" type is what I want, it also looks stronger.

Now, the "shank" column is more tricky.
I thought "RH" and "LH" and "center" determined whether the knurls are captive right in the middle or slightly offset to one or the other side, to increase the capability to knurl close to a shoulder (but not right to).
On this image, the knurls are clearly offset to one side, my interpretation is that this is a LH type scissor.





But then I found the PDF document showing this :





Now I don't understand. The PDF show that RH/LH/Center modifies the height of the scissors relative to the shank. What does that have anything to do with the RH or LH nature of the scissors ?

I would speculate the strongest shank type is either the center type or round type (which is centered also). If the height is set properly, the scissors are totally in line with the shank and that I think is desirable. Also, I think a bigger shank can be used with a center type without bottoming out on the QCTP.

Finally, not sure what's the point of the "round" type shank, unless one has a boring bar holder laying around ?

So I would think what I need is :
- shank (not round) and center type
- 5/8" or 3/4"
- simple "form", not "counterbore"

$80 for that knurled ? One heck of a deal 
unfortunately usually sellers don't ship outside of CONUS or at a huge cost...


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## darkzero (Dec 3, 2014)

Interesting, was not aware of that & the shank offsets. Seems like to me the LH is oriented that way for CNC machines where the tool is sitting behind the workpiece (unlike a conventional machine where the tool post & tool is in from of the workpiece directly in from of the operator. 

The one I have would be like the right hand shank shown in the diagram. Mine looks like the photo you posted (wheel placement, not the shank). I always assumed the LH & RH were like the one shown below on the right, wheel placement oriented for a shoulder.


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## Jumpmaster (Dec 11, 2014)

I've just finished reading this entire thread...very impressive knurling throughout!!!

While trying to find tutorials on youtube, I ran across this series of videos and it was helpful to me to see someone talk through the process. Hope others find it useful.

This is the first video, but there are four all together...

https://www.youtube.com/watch?v=j4jIzRGAhvM&app=desktop


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## precisionworks (Dec 11, 2014)

The two I use:











The one directly above allows knurling right up to a shoulder. Also, wheel changes take almost no time because of the set screw. On the other knurler the pins have to be pressed out, wheels changed & pins pressed back in ... so I don't ever change those


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## tino_ale (Dec 11, 2014)

Very valuable information. I did not know the one above had pressed pins, I assumed a set screw system!

As I have no access to a press, sounds like a deal changer. Unless the pins can be swapped out using a simple general purpose bench vise ? I have one (Old but new French iron "Sambre et Meuse" vise). I don't think I will have to change the wheels often at all but I don't want that to be a PITA operation.


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## precisionworks (Dec 12, 2014)

tino_ale said:


> As I have no access to a press, sounds like a deal changer. Unless the pins can be swapped out using a simple general purpose bench vise ?


One of the other members may have done this without a press & perhaps will comment on how to do it.

I don't believe there are as many styles & pitches of knurls available with the setscrew-pin type because the knurl is counterbored & the pin is headed. The normal knurl uses a straight pin & straight reamed hole in the knurl. IIRC there were no convex knurls available.


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## darkzero (Dec 15, 2014)

> tino_ale said:
> 
> 
> > I did not know the one above had pressed pins, I assumed a set screw system!
> ...



The standard K1-201s uses friction fit pins & the heavy duty K1-44s use pins held in by set screws. That is one of the ways to tell the difference between the two models. The K1-44 Barry pictured is obviously the type that can knurl up to a shoulder & is what I was talking about in posts 112 & 114. 

So I looked in MSC's catalog & Eaglerock's website (wow they went up another $50 since the last time I looked). The K1-44s that knurl up to a shoulder are the L-series & looks like they use metric wheels. Like Barry mentioned, there are no convex wheels available in the size it uses, not from Accu-Trak anyway. The K1-44 that uses straight pins are the E-series & they use standard wheels (KPV). That is the one I have.


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## tino_ale (Dec 15, 2014)

Good news 

I'm going to go with that, all I need to check is the size and style of the shank (LH/RH or center).


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## wquiles (Jan 10, 2015)

Latest knurling project - a custom brass expanding insert for my 44Mag reloading dies, made from 12L14 steel. 







Original on top, new one on bottom:












Will


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