# CXA or BXA for PM-1440GT



## jaychris (Jun 27, 2017)

Anyone running a BXA toolpost on their PM-1440GT?  I was running an Aloris BXA toolpost on my older Jet 14x40 and had no problems.  Shifted it over to my new PM-1440GT, and I'm finding that the toolholder sometimes either needs to run at the very top of it's travel to reach center, or doesn't have quite enough travel to reach center for a particular tool (usually a small boring bar).

Before I run out and buy a CXA toolpost and new holders (<sigh>), I thought I'd ask and see what other PM-1440GT owners are doing.


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## davidpbest (Jun 27, 2017)

Jbolt moved from BXA to CXA on his 1440.   The thread where he discusses it is here:   http://www.hobby-machinist.com/threads/cxa-qctp-on-the-pm-1440gt.57630/


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## jaychris (Jun 27, 2017)

I guess that answers my question.  Thanks!


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## Buffalo20 (Jun 27, 2017)

We got a new lathe at work (new to us).its a 14" x  60",  Taiwan sourced lathe. The BXA seems a little small and they where talking about a CXA QCTP and related blocks, and still may get one, down the road, for the time being, because of the number of blocks, currently in use, they put a 1/4" spacer under the BXA block, at this time the operators seem happy.


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## jaychris (Jun 27, 2017)

Buffalo20 said:


> We got a new lathe at work (new to us).its a 14" x  60",  Taiwan sourced lathe. The BXA seems a little small and they where talking about a CXA QCTP and related blocks, and still may get one, down the road, for the time being, because of the number of blocks, currently in use, they put a 1/4" spacer under the BXA block, at this time the operators seem happy.



yep, that's what I've been doing, using a spacer block to set the height when I can't set it with the tool holder itself.  The CXA toolpost that jbolt bought in that other thread seems like a pretty reasonable deal though.


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## Buffalo20 (Jun 27, 2017)

Do you take it out or did you reset the heights and keep the block in all the time??  At work it now a permanent part of the QCTP/compound assembly.


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## jaychris (Jun 27, 2017)

Buffalo20 said:


> Do you take it out or did you reset the heights and keep the block in all the time??  At work it now a permanent part of the QCTP/compound assembly.



I've just been using it to set the height of the toolholder and then removing it.  It only works for one right now, though it gets the others close.  I really only end up using about 8 tools on a consistent basis, but 3 of them need to be set with the block and it's not perfect for 2 of them.  It seemed easier in the long run to go the CXA route, rather than looking at having to create a bunch of setup blocks to set different tools on center...


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## bfd (Jun 27, 2017)

I installed a shim under my bxa to allow for the tool holder height to be closer to the middle this might work for you. I used a piece of starrett ground tool steel so it would be flat. size it for your needs bill


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## jbolt (Jun 28, 2017)

Jay,

Before you jump into a CXA just for height consider that the CXA QCTP is only 1/4" taller than the BXA and the CXA holders are larger so it will be worse for smaller tools. Aloris, Dorian and Shars all publish the dimensions of their tool posts and holders. Best to do the math first.

The smallest HSS tool bit I can use on my PM-1440GT with the CXA tool post without shimming is 3/8" so for a boring bar where the cutter is at the center of the tool a 3/4" bar is the smallest I can use without shimming. I use shims in the tool holder under my boring bars that are smaller than 3/4".

The advantage for the CXA is an increase in rigidity (to a point on the compound) and being able to use larger insert tooling. The BXA is perfectly adequate for most hobby use.


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## pstemari (Jul 1, 2017)

If boring bars are the problem, making some bushings and using a through-hole holder like a #41 should fix the problem.

Sent from my Pixel XL using Tapatalk


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