# Got the new knurling tool working



## Mirage_Man (Mar 29, 2009)

After leaving the knurling tool alone for several weeks I went back and tried again. It appears that I've at least figured out how to do a single band without it double tracking. The next step will be traversing a part. I have a pretty good idea how to accomplish that but for now I'm very pleased that I was able to do this.

Here's a pic of a ti tail cap I'm working on today.


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## StrikerDown (Mar 29, 2009)

Dude! That looks sweet!:thumbsup:


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## Anglepoise (Mar 29, 2009)

Looking good.


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## SafetyBob (Mar 29, 2009)

What did you do different or how do you think you made it work so well?

Looks REALLY nice!!!

Bob E.


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## jch79 (Mar 29, 2009)

Nice Brian! Lookin' good. 

Hope all is well.


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## Mirage_Man (Mar 29, 2009)

Thanks Guys. I really am tickled to get this to work. Knurling in general can be a real bugaboo but in ti it's even more of a PITA to do well. 



SafetyBob said:


> What did you do different or how do you think you made it work so well?
> 
> Looks REALLY nice!!!
> 
> Bob E.



Bob, I spoke with a fellow at Eaglerock a day or so after the first time I attempted it. He explained as best he could what to do the the particular tool I have. At that point I was pretty frustrated and didn't want to waste any more expensive ti material so I went on to other projects until the other day. I decided to give it a shot with some aluminum stock to see if I could get it to work. The result was pretty good. Good enough that I decided to risk trying again in some ti stock. Here is the result in that piece of ti.










The only info I can pass on is if you have the same tool I do. It's a little lengthy to go into here though. When I have some more time I'll do a write up on how I did it.


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## wquiles (Mar 29, 2009)

Mirage_Man said:


> The only info I can pass on is if you have the same tool I do. It's a little lengthy to go into here though. When I have some more time I'll do a write up on how I did it.



Looking great Brian, and yes, please do tell 

Will


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## nekomane (Mar 29, 2009)

Scissor type or one sided? Which do you recommend?
Nice job as always


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## Mirage_Man (Mar 29, 2009)

nekomane said:


> Scissor type or one sided? Which do you recommend?
> Nice job as always



This one.


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## Anglepoise (Mar 30, 2009)

Mirage_Man said:


> The next step will be traversing a part. I have a pretty good idea how to accomplish that but for now I'm very pleased that I was able to do this




Can help you with one tip when you try to make a long knurl ( traverse ).

Nice thing about these scissor knurls is that they take allot of the strain off the lathe spindle bearings. However there are still huge pressure/strains going on. When you try to traverse the carriage to lengthen the knurl ( Ti ) , the strain will try to pivot around the tool post and unless it is very secure it will move.

To stop this on my lathe, I finished up having to 'pin' the toolpost to the topslide. Amazing amount of pressure must be involved.

In Ti, I prefer the look of your knurl where you do not try for full depth.
I think full depth knurling in Ti is only really successful ( looks nice) with a cut type knurling tool that Fred and others use.


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## precisionworks (Mar 30, 2009)

> cut type knurling tool that Fred and others use.


+1

The cleanest "knurling" on hard & tough materials is done on a CNC lathe, using a live spindle tool. The tool looks like a very small saw blade, with the tips forming a 60° included angle. The tools spins in the live spindle as the tool is moved against the slowly turning part. After the spiral is made in one direction, the spindle and tool are reversed.


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## jhanko (Mar 31, 2009)

Mirage_Man said:


> The result was pretty good. Good enough that I decided to risk trying again in some ti stock. Here is the result in that piece of ti.



That knurl looks great. I'm just curious, did it track that good the first try or did you have to fiddle with the OD?


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## Patriot (Mar 31, 2009)

Gosh that looks amazing! I feel as if I'm looking at fine custom pistol parts whenever I see your work. That's just beautiful.


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## jhanko (Mar 31, 2009)

precisionworks said:


> The tool looks like a very small saw blade, with the tips forming a 60° included angle. The tools spins in the live spindle as the tool is moved against the slowly turning part. After the spiral is made in one direction, the spindle and tool are reversed.



I would love to see this in action. Anyone seen a video anywhere?


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## ICUDoc (Mar 31, 2009)

precisionworks said:


> +1
> 
> The cleanest "knurling" on hard & tough materials is done on a CNC lathe, using a live spindle tool. The tool looks like a very small saw blade, with the tips forming a 60° included angle. The tools spins in the live spindle as the tool is moved against the slowly turning part. After the spiral is made in one direction, the spindle and tool are reversed.



I think Fred (PhotonFanatic) has a cutting knurler like that? I may be wrong but maybe he will write that up too....
Knurling is an unexplored lathe technique for me- looks too hard!


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## cmacclel (Apr 1, 2009)

JHanko said:


> I would love to see this in action. Anyone seen a video anywhere?


 

Data has his video up on You-tube 

http://www.youtube.com/watch?v=mGCRNybrRY8&feature=channel_page

Mac


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## precisionworks (Apr 1, 2009)

That's exactly the tool that I've seen used, but cannot find a name for it. Thanks for the video link.


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## jhanko (Apr 1, 2009)

cmacclel said:


> Data has his video up on You-tube
> 
> http://www.youtube.com/watch?v=mGCRNybrRY8&feature=channel_page
> 
> Mac



Thanks for the link. Does it have to be that slow? Seems like it would take a long time to do a conventional knurl job on a light...


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## Anglepoise (Apr 2, 2009)

JHanko said:


> Thanks for the link. Does it have to be that slow? Seems like it would take a long time to do a conventional knurl job on a light...



Reason it is slow is because the video is not showing an example of 'knurling'

Data is basically making flutes or grooves around the circumference of his switch knob. I can't see in the video but if the cutter is stationary than he is 'shaping' and if the cutter is revolving, then it's 'milling'.
But it is not knurling in the traditional sense. Knurling when set up in production is very fast and efficient.


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## Mirage_Man (Apr 2, 2009)

Here is a video I took when I was having my split bodies made at a CNC shop. In theory they did it right but unfortunately they didn't get it totally right. A good knurl should not need to be "knocked down" afterwards as they did.


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## bmstrong (Apr 2, 2009)

>>The next step will be traversing a part.

I'm still looking for a simple CR123 Ti twisty with a full knurl if you want to do a paid experiment...


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## precisionworks (Apr 2, 2009)

The desired end result might be described as metal checkering, which leaves a pattern similar to that on a pistol grip or a shotgun forearm. There are different ways to achieve a checkered pattern. 

The oldest, slowest, and most labor intensive method is cut checkering. A V-shaped file is used for flat or slightly curved surfaces, with two passes at some angle. Cut checkering is easily done on a CNC mill, like this photo shows (.45 Auto front strap):







Cut checkering (aka cut knurling), whether manual or machine applied, is a *metal removal* process. The diamonds are created by removing unneeded metal. This can be done in the round on a lathe, either manual or CNC, by setting up as if the part were being threaded, using a single point threading tool. After the thread is cut to full depth with the tool moving toward the headstock, the operation is repeated with the tool moving in the opposite direction. It's still a slow process, because metal removal is limited by the ability of the single point to remove metal. If a multi-point tool is used instead, the process goes much more quickly - which is what Data does on the knob for the Spy 007. 

Impressed checkering is a *metal displacement* process. On a flat surface, a negative image stamping die would strike the metal, which cold forms the diamonds in the pattern. Round parts are checkered by roll forming with a pair of opposing rollers that each bear a negative image form that creates the diamonds ... also called knurl rolling, or knurling. Displacing metal is almost always faster than removing metal, which is why knurling is such a popular method in industry. The biggest drawback to knurling is that harder & tougher metals like Ti require great pressure before the metal cold flows into the desired pattern. On the other hand, most aluminum alloys cold flow like butter (in a relative sense), so less pressure is required to achieve a full depth pattern.


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## kaichu dento (Apr 2, 2009)

Great post Precisionworks! Thanks for explaining it so well!


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## PhotonFanatic (Apr 2, 2009)

precisionworks said:


> That's exactly the tool that I've seen used, but cannot find a name for it. Thanks for the video link.



Double angle cutter, although there may be other names as well.


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