Using 1/2" tool holder in an AXA tool post.

[GunsOfNavarone]

It's questionable to post this under blunders, for me it ended up being slightly. So I have a 10x22 lathe and cha he's to a AS TO size AXA. I initially purchased 3/8" tool holders but found the inserts style somewhat limited. I figured since my tool post would hold 1/2" holders, they would be more rigid and give me more options. I purchased a Kennametal and placed in the tool post, even at the lowest adjustment, it was slightly above center. I ended up putting the tool holder in the mill and shaving a couple mm's off the bottom side and it worked out.
So here is my question, just because my tool post will hold 1/2" holder, doesn't mean it will work, but am I missing something ? Are there 1/2" holders that have different center position? I hated taking a pricey new holder and milling it down, but was gonna deal with my mistake as it wasn't the sellers fault. Is the the normal protocol?
Thanks guys

 

[mikey]

Yup, par for the course. Your 10" lathe isn't really rigid enough to require 1/2" tooling anyway so I suggest you stick with 3/8". The tools will cut the same as the larger tool but you'll be able to get it on center. I have an 11" lathe and use 3/8" tooling - cheaper, fits better and works just as well.

 

[darkzero]

That's common, it depends on the lathe (compound slide to spindle centerline height. I used to have an 8x14 lathe with an AXA tool post. There was a company that actually sold the QCTP holders with the bottom already shortened. They went out of business & I then had regular AXA holders milled myself by someone local (I had no mill at the time).

Most Aloris style QCTPs are the same as they are clones of Aloris' dimensions with some exceptions. If you buy oversized tool holders, the slot will differ in size & location a bit. Some people mill down their compound slide to account for this, others mill down the shank of the tool. I would much rather mill down the tool holders.

 

[darkzero]

I agree with Mike in that for the size lathe in question you aren't really gonna be able to tell the difference in rigidity between 3/8" & 1/2" shank tools unless you are hanging them way out if/when needed.

However looks like the OP is using indexable tools. When it comes to that there are more indexable tools offered in 1/2" than 3/8". Same goes for BXA, much more indexable tools available in 5/8" than 1/2". Of course with smaller lathes HSS will be perfectly fine for basic turning but there are some indexable tools that have an advantage over HSS depending on the operation and/or materials being machined. I have a 12x lathe with a BXA tool post, with standard holders I can use 5/8" shank tools but I still use 3/8" & 1/2" shank tools also.

 

[tazzat]

If you Want more rigidity you can remove the topslide and make a plate to fit the AXA. Put it back on only if you need it..
I lowerd my topslide so i now can user 1/2" tools.. had the same problem.

 

[GunsOfNavarone]

So the moral here...just because you can, doesn't mean you should. Someone pointed that out here that you can buy XL axa holder to take 5/8" tools. ..why?!
Also like mentioned here, it wasn't completely the rigidness, it was the options on inserts.

 

[pontiac428]

I have four nice HSS tools in 5/8" that I use on my 10" lathe in an XL AXA holder (which is right in the middle of its vertical travel). Just goes to show it's the lathe and not the tool post that dictates what can be used. It simply moves the vibes and flexes further down the line, into the tool post bolt and through the compound assembly. Not much I can do to improve that. I don't use the big tools because they're stiff, I use them because they have great grinds, similar to why the OP was using his oversize tooling.

 

[RJSakowski]

Aloris and Shars sell XL tool holders for for 5/8" tools for the AXA toolpost. This was sufficient to drop the 1/2" tools to hit slightly below center on my G0602 10x22. The Shars no. is 250-101-XL and the Aloris no. isAXA-1S. Metric tool holders come in 12 mm size which buys you another .028". Also different manufacturers have different dimensions for the floor thickness and the dimensions don't always conform to the nominal spec so its worth axctully measuring them to see what works.

 

[RJSakowski]

So the moral here...just because you can, doesn't mean you should. Someone pointed that out here that you can buy XL axa holder to take 5/8" tools. ..why?!

The XL tool holders drop the floor slightly to accommodate the 5/8" tooling which lowers the minimum height for 1/2" tooling.

 

[mmcmdl]

I've been finding lots of AXA tooling and adaptors from long past going thru the drawers lately . Included were offset drop blocks I made for holding larger tools on the Hardinges . They work great if going with the larger insert tooling and it only costs you 1" max on your cut length .