Diamond tool holder

[mikey]

That only bit that I can’t figure is how your grind a chip breaker in the top of the bit.

If you think you need a chipbreaker, free hand grind it. You will need to grind a V-shape just back from the side cutting edge; the center of the V will parallel the side cutting edge. Why not try it and see if it is effective enough that its worth your time to grind it. As an alternative to a chip breaker for stringy materials, increase your feed rate.

 

[higgite]

Tangential tools do a good job of hogging off aluminum on my bench lathe. I haven’t tried one on steel, though. I tried cutting a chip breaker in one of the tool bits to no avail.

Rick Sparber made and published a DIY add on chip breaker that looks sorta weird but seems to work pretty well, but I haven’t made one to try myself.

https://www.rick.sparber.org/ttcb.pdf

Tom

P.S. To answer your question, David, yes, I have 2 of the Eccentric Engineering Diamond Tool holders.

 

[ddickey]

The other plus of the Eccentric Engineering made tool is that you can make a face cut without turning the holder.

 

[Hawkeye]

The compound on that poor Hercus has seen some action...

Yeah, Dan. The only viable explanation is that it used to be a high school shop lathe. No one machinist, no matter how bad, could possible have that many chuck strikes.

IIRC, the geometry is: 15* to the left, 15* toward the work, and the tool bit ground to 30* diagonally. The radius on the cutting edge is up to preference.

 

[Aukai]

I just mounted mine today, and made some facing, and turning cuts on an unknown steel bar,it made curls, and it does seem to work ok. Then did my first practice knurl.

 

[Downunder Bob]

G'day Dave, Yes the Eccentric Engineering diamond tool holder. I have one and love it, it is my go to when using HSS The positives are:

1. Very easy to grind your own tools,

2. You can use broken centre drills and milling cutters, taps, anything round, square or even hex of about the right size will work.

3. Most users report the ability to take heavier cuts than with conventional tool holders Ability to face and turn in the same setting.

the only negative I am aware of is they are a bit pricey, but as others have said you can always make your own, but certainly worth having.

 

[savarin]

I have a left and right Eccentric Engineering diamond tool holder.
Love em.
I've also used then somewhat unconventionally.
https://www.hobby-machinist.com/threads/80mm-long-focal-length-refractor.26212/page-2 message 54
and a better view in message 61 with a different tool bit.

 

[GunsOfNavarone]

Man...no doubt that's a big machine they demo those 1/2" DOC runs...but I want it. The only downfall for me is I just don't want to use HSS...I know..go ahead and flame. That does seem uber versatile, I might take that plunge..
Just shot an email to them, unsure of what is best for my lathe. Since this is coming from Australia, I don't want to screw the pooch. Thanks for the lead David!

 

[Illinoyance]

I decided to make my own. They work great. I started the project without even having a sketch. It turned out to be a LH tool. I then made the RH tool.
If used only for turning one could grind a groove type chipbreaker across the end of the bit. Grind the groove in the other direction for facing.
I got the idea from looking at the grind on the bit for a box tool.

 

[Ulma Doctor]

the tangential holders look interesting, i have not tried them.

a little off topic here, but
i f you got a bit of time to spare, have a look at a tool that our beloved @mikey expertly ground on his belt sander.
(this tool is being used on a small metal shaper to take ridiculously heavy cuts in aluminum)

i have seen that you are aware of @mikey 's thread on HSS tool modeling, great stuff!!!