# interesting boring bar ...



## wquiles (Feb 15, 2009)

I have no problem with a nice finish on internal boring with my carbide boring bars up to 1xD hosts, but when doing 2D hosts (basically boring 6 inches inside the tube) I got a good finish, but not as nice as I wanted. And I don't mean a mirror finish - since that is not my goal either, just a nice, even finish - purely subjective, just trying to do better every time 

While attempting to improve on the finish for internal boring, with help from Brian (Mirage_Man) have been trying a couple of things, including playing with the auto carriage feed, and using a bigger bar. Today I decided to try the "big" bar, one that I got on Ebay as part of a lot almost a year ago - it is made of steel, 12" long, 1" dia, which came with some "inserts". It is the inserts that are interesting since this bar uses some "strange to me" boring/grooving tool bits, some purpose built to fit the groove, but also a standard round tool bit:










































I ended up trying the round tool bit, which had very unique manually ground angles/releifs/etc. - somebody either was just playing with it, or they knew exactly what they were doing!:
















I tried to touch it up on my tool grinder (HF on special!), while following the original angles, and after getting the bit aligned (tricky since it is round!), I tested it on this piece of "scrap":






The tool material was a tad soft, since it got a little bit more rounded after use, but it did give me a better finish, on the actual 2D body for a customer:






Looks like after all it was a nice buy from Ebay 

Will


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## markc987 (Feb 16, 2009)

I dont know much about machining but those are beautiful clear photos. Very informative. What did you use to take them?

Mark


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## bretti_kivi (Feb 16, 2009)

# Camera Make = FUJIFILM
# Camera Model = FinePix S100FS 

I was wondering, too. Just goes to show, you don't need a DSLR


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## Anglepoise (Feb 16, 2009)

Will
It has been my experience that any time your setup can handle a rounded cutting tip, you will get a smoother finish. However on tubing that will flex, the rounded nose will be deflected as it tries to cut.

That's why these 'wiper' inserts are so popular. They smooth out the peaks and valleys. If you break it down, regular turning is basically threading if you look at the finish under magnification. 

On thin wall tubing ( mags etc ) vibration is my problem and I can improve my finish by reducing the vibration. I use rubber bike inner tubes 
( stretched over the workpiece for internal work ) and other rubber type products to dampen things down a bit.


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## precisionworks (Feb 16, 2009)

I hve one smaller bar, maybe 3/8", that uses an identical insert. If you need a special grind, draw out the angles & send it to me - I'll grind it on the surface grinder using the UniVise which articulates in four axes.

http://www.metalworking.com/Dropbox/DeltaToolGrinderCatlg5-7-pdf.pdf


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## kromeke (Feb 16, 2009)

Looks to be an Everede or Everede style boring bar. The bits you have might be custom ground. 

Here is a link:
http://www.everede.net/Boring_Bars_30.html

-Keith

Edit: Yours looks like the 15 degree bars. Look at their website for more info, under non-indexable tooling.


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## precisionworks (Feb 16, 2009)

> Looks to be an Everede or Everede style boring bar.


Good find, Keith ... I always wondered who made mine. The only markings on mine are 

*R.B. BHJ1*

Mine has a 3/4" mounting shank, and a 3/8 bar, about 2" long on the reduced diameter.

Some bars come with a reference flat already machined, others have none. It's really handy to machine or grind a reference flat so the bar & tool point index to the same height each time it's installed.​


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## wquiles (Feb 16, 2009)

markc987 said:


> I dont know much about machining but those are beautiful clear photos. Very informative. What did you use to take them?
> 
> Mark





bretti_kivi said:


> # Camera Make = FUJIFILM
> # Camera Model = FinePix S100FS
> 
> I was wondering, too. Just goes to show, you don't need a DSLR


Yup. It was set to Macro (it also supports super Macro mode), and setup on full auto/program mode, with the lens set to full wide angle. I had in fact a more "fancy" Canon Rebel XT with a 24-105L Lens, but I sold it to get this smaller, handier camera, which also does better macro photos without having to change lenses 




Anglepoise said:


> Will
> It has been my experience that any time your setup can handle a rounded cutting tip, you will get a smoother finish. However on tubing that will flex, the rounded nose will be deflected as it tries to cut.
> 
> That's why these 'wiper' inserts are so popular. They smooth out the peaks and valleys. If you break it down, regular turning is basically threading if you look at the finish under magnification.
> ...


Yup, I noted exactly that you said, when I moved the bar against the Mag - instead of biting/cutting, it flexed over a little bit  . Thanks for the tips on vibration 




precisionworks said:


> I hve one smaller bar, maybe 3/8", that uses an identical insert. If you need a special grind, draw out the angles & send it to me - I'll grind it on the surface grinder using the UniVise which articulates in four axes.
> 
> http://www.metalworking.com/Dropbox/DeltaToolGrinderCatlg5-7-pdf.pdf


No worries - this will be a good learning experience on my grinder, although, I would love to find something like the UniVise to add to my shop :devil:




kromeke said:


> Looks to be an Everede or Everede style boring bar. The bits you have might be custom ground.
> 
> Here is a link:
> http://www.everede.net/Boring_Bars_30.html
> ...


AWESOME - I had no idea what it was until now - thanks much 




precisionworks said:


> Good find, Keith ... I always wondered who made mine. The only markings on mine are
> 
> *R.B. BHJ1*
> 
> ...


Mine had no reference flats anywhere - just a pure round bar.


Will


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## 65535 (Feb 17, 2009)

Will you might be able to get some carbide drill blanks and grind them into inserts with a diamond grinder.


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## precisionworks (Feb 17, 2009)

> carbide drill blanks and grind them into inserts with a diamond grinder.


HSS drill rod is also useful for this purpose. Available is O1, A1, & W1, it's inexpensive in 36" lengths. W1 is the easiest to harden in the shop, as you simply heat it with a propane torch to dull red/medium red, and quench in cold water ... that produces about 67 HRc hardness, which is glass hard & still needs to be drawn down. Place the hardened part in your kitchen oven, set to 450F, leave it for an hour, and the part will test about 60 HRc, which is equal to a commercial tool bit.

Using HSS drill rod, the tools are ground to shape while the material is in the soft (as received) condition. After hardening & tempering, they are touched up on a bench grinder or tool grinder & are ready for use.


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## 65535 (Feb 17, 2009)

That's a good point too PW. I just am a sucker for all things near diamond hardness.


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## wquiles (Feb 17, 2009)

precisionworks said:


> HSS drill rod is also useful for this purpose. Available is O1, A1, & W1, it's inexpensive in 36" lengths. W1 is the easiest to harden in the shop ...


So W1 is easy to harden in the shop, but is O1 and A1 that much harder to work with? Does it mater much for the tool bits we are talking about in here?

Will


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## precisionworks (Feb 17, 2009)

> > I just am a sucker for all things near diamond hardness.
> 
> 
> +1
> ...


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## wquiles (Feb 17, 2009)

precisionworks said:


> Their transition temp range is more critical, and quenching O1 in oil is nasty, smoky, sometimes with a small fire added:shakehead A1 is air quenched, but is more pricey.
> 
> W1 is the least expensive, & easiest to harden, quench & temper. It isn't the perfect tool steel for every application, but it's nearly impossible to mess it up using nothing but a propane torch, water bucket, and kitchen oven.



Thank you - I will be ordering some W1 on my next Enco order 

Will


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## brickbat (Feb 17, 2009)

precisionworks said:


> ...
> Using HSS drill rod, the tools are ground to shape while the material is in the soft (as received) condition....



Can W1 material be milled or otherwise machined with HSS tooling before its hardened? Can it be tapped?


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## 65535 (Feb 17, 2009)

Properly annealed W1 is about the same as a mild stainless steel. Hardened and it's the tool. 

As and aside, W1 is a favorite steel for budding knifemakers for the reasons PW mentioned.


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