AXA or BXA???

My lathe has 12in swing. The original poster has 10in swing.
Lathe swing is not what determines which tool post fits your lathe. It is only the dimensional difference between the spindle center to tail stock center axis and the height of the top of the compound rest. The idea is that you want to be able to get your smallest desired tool bit size and your largest desired tool bit size at work center height, by using only the knurled adjusting nuts on the tool holders. Lathe swing does not enter into that equation. Yes, tool post makers advertise their tool post sets by lathe swing, but they are only doing their customers a disservice. Sorry, t'aint that easy.
 
As someone else mentioned you can also trim down the lathe tool themselves to fit. My main carbide left and right set are 3/4 shaft that I cut to 5/8 and they work perfectly. I went with those because they also came with likely a lifetime supply of carbide inserts.
 
I went with those because they also came with likely a lifetime supply of carbide inserts.
Large tooling is also more rigid, and cheaper on places like eBay. I do the same, but I am using BXA holders, and oversize BXA holders will hold 3/4" shanks. They are far more rigid than smaller shank tooling, and the work tends to have a better finish and better accuracy. Downside is that the big tooling can get in the way on small work features, so smaller tooling is needed as well. I use 3/8 to 3/4" shank turning tools, and a couple times have used 1/4" tools, and of course much smaller yet with boring bars and other tooling. I try to use the biggest tool that will do the job, all else being equal.
 
I hate to bring this up but a typical QCTP is no more "rigid" then a 4 way tool post system, quite likely less so. It will not magically improve performance by removing existing machine weakness.

It is exactly what the name implies "quick change", this is not inherently "better" then any other system merely easier.
 
No one brought up QCTP for rigidity or other performance.

It is the quick change that is so magical. Sure a 4 post or a lantern post can hold a tool and very well. Magic comes with changing tools in 2 seconds or less and have it stay set to work repeatably. Other holders require breaking out Allen wrenches or maybe a square key wrench for a lantern and then much of the time also shimming and re measuring for height.

Easier in this particular case is not mere.
 
I see that you have a turret lathe, I fully understand your dislike of fixed tool posts. We have a W&S #5 that will push a 3" drill right through a 6" long stainless round, turn on the spindle and engage the turret feed, come back when it stops making noise. Now that is magic.
 
I hate to bring this up but a typical QCTP is no more "rigid" then a 4 way tool post system, quite likely less so. It will not magically improve performance by removing existing machine weakness.

A good QCTP is quite rigid - they work great. I had a 4 way turret and it certainly had better support right out under the tool holder. When I changed to a PhaseII QCTP - CXA I did not notice any change in how well the tooling performed. The QCTP works great.

I modified the holders on my smaller machine so they sit right down on the top of the compound - it is probably more rigid, but that is not why I did it. I have a S&B 1024, which is an 11" lathe. I got an "E" size 40 position holder because it will take the 3/4" tooling I already had in the standard holder. Right off the start I bought enough holders so that the common use tooling will remain in that holder "forever". That set up put the tool 0.150" too high, so I skimmed the bottom of the holders, just to the point that when all the way down it would land right on center. The weanie little adjusting screw and bracket were removed. The result is fast, solid and stacks neater in the top of the tool box. I trimmed too much on one of the holders - so just glued some shim to the bottom of the holder. Obviously I have other holders, with the bottom skimmed and still with the adjusting screw.

It is a good arrangement. One could do that with about any holder that you have dedicated to specific tooling - glue a shim to the bottom of the holder or clamp one under the tooling, then the holders sit right down. I would have changed out the square head bolts that clamp the tool, but I couldn't find set screws 7mmx1mm/t

I found I had to tune the actual holder and tool - all 3/4" tooling is not the same. There can easily be 0.025" difference in height from a straight turning tool, to the facing tool, to the parting tool.

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A good QCTP is quite rigid - they work great. I had a 4 way turret and it certainly had better support right out under the tool holder. When I changed to a PhaseII QCTP - CXA I did not notice any change in how well the tooling performed. The QCTP works great.

Indeed, simply pointing out that many people new to the business seem to assume that a QCTP being 30 years newer technology then their 1930 lathe is naturally better in all ways. I find them quite useful when switching from job to job quickly.

I suspect that you and I work in very different facets of the machining industry.

 
Indeed, simply pointing out that many people new to the business seem to assume that a QCTP being 30 years newer technology then their 1930 lathe is naturally better in all ways. I find them quite useful when switching from job to job quickly.

I suspect that you and I work in very different facets of the machining industry.



That is impressive. Wreck, got to tell ya, I am envious of you actually living the life, being a machinist. I am just a hobby person - day job in an office. Got that Warner Swasey Turret lathe (1928 model) answering a classified ad in the paper saying "Metal lathe" I thought it was going to be a bench top lathe but it is a massive beast for my home shop with my Bridgeport. $900 delivered to my shop. That one has a CXA size QCTP, came with a lantern post and a supply of old style tool holders so I had some experience with that to start. Most of my work is done on a smaller Wabeco D6000E German made precision lathe with AXA QCTP.

If anyone has room those old large manual lathes sometimes go inexpensive and mine is all fully functional, all geared power feeds, etc.
 
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