Is a QCTP less rigid than the standard one supplied

T

TQA222

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I had sort of made up my mind not to bother with the QCTP route. I am retired and will be taking my time with every step so the extra minute or two to change a tool is not significant.

But I am aware that rigidity is an issue especially when turning steel.
So which is the most rigid

the original 4 sided toolpost

OR this ali QCTP at 25$

OR the LMS steel one
 
Properly assembled,I'd think they are about equal. All three beat out the Lantern type.
 
I think the 4way post is the most rigid. It is also very cumbersome to use. I would go with a QCTP.
 
I would think either of the steel choices are gonna be more rigid then the aluminum versions.
To add to what Mikey was saying the stock tool post is not just Slow it is Cumbersome and aggravating because of the way you need to "Shim" your tooling with multiple/different thickness shim stock in order to meet centerline....this is not always the easiest thing to do and by comparison a properly setup lantern style tool-post can be more user friendly in this aspect IMHO. So for this very reason alone I would suggest the qctp as well.
 
On my flexi 9x20 lathe I found that it wasnt the tool post that was the problem it was the top slide.
I could visually see the tool post flex under some loads irrespective of whether I used the 4 way post or the qctp (wedge type from china, cheap).
Eventually I removed the top slide and replaced it with a solid plinth with a qctp. The difference is like chalk and cheese, way more solid.
I thread at 90' thats not caused a problem to dat, I only replace the top slide when I want a small taper cut.
 
I've mentioned this on several other threads, so please forgive if you've read this before.

A 4 way toolpost is not slower than a QCTP for most operations. All you have to do is mill the tool body (for an insert type) so that the tip is on centre. then never again do you have to worry about the tool height. ever. change an insert, it's on centre.

For long operations where I use a turning tool, a facing tool, a chamfer tool, then a boring bar, I can put them all in my 4 way and index them as I need them. Yes, it is a picky setup to mill then grind the tools so they are on center, (you only ever do it once) but the superior rigidity and ease of use has me still using my 4 way tool post often.

-- Don't get me wrong, I have an AXA on one lathe and a BXA on the other. they are wonderful. I have tools and situations where I'm happy to swap out the 4 way, and use the Aloris style. When it's good, it is very good! (Yes I have about 20 holders for each tool post)

When I'm turning wood, or doing internal grooving in steel, I use the lantern exclusively. Yes I still use all 3 tool holders. I also find it easier to use small HSS tooling in a lantern.
 
I think it is more the type of work you will be doing. For production work, a 4 way tool post will be fast to do tool changes, but slower to make a new setup for a new job. The quick change tool post (QCTP) will be quicker to adjust to new operations on new projects. Both are rigid when set up correctly. Aluminum has a much lower modulus of elasticity, which means it flexes more, which also means it is less rigid...
 
...Back to your original question: On my 12X37 lathe, the 4 way is far more rigid. It shows mostly when parting off, but also allows me to take deeper cuts or faster cutting rates. Mostly I take light cuts on that lathe anyway.

On my 10X40 lathe with the BXA, there is no noticeable difference in rigidity between the 4 way or QCTP. Most of the play is in the compound slide anyway.

-- I hope this helps!
 
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