What size QCTP to buy?

[mklotz]

The price of QCTPs is getting low enough that I'm considering buying one.

The AXA size set is down to $99

http://www.use-enco.com/CGI/INSRIT?PMAKA=505-2253&PMPXNO=953080&PARTPG=INLMK32

while the BXA is $119

http://www.use-enco.com/CGI/INSRIT?PMAKA=505-2172&PMPXNO=953248&PARTPG=INLMK32

I need to decide which of these is the best fit to my 12" lathe. In the "SPECIFICATIONS" box on this catalogue page:

http://www.use-enco.com/CGI/INPDFF?PMPAGE=494&PMCTLG=00

they seem to imply that 12" is the upper limit for the AXA size and about mid-range for the BXA size.

On my lathe the spindle centerline is 1.19" above the top of the compound so whatever I buy has to be able to raise the top of the toolbit to that height. Will an AXA be able to do that or do I need to get the BXA?

 

[black85vette]

On the CDCO web site they have them for $78 and $95.

http://www.cdcotools.com/

As I read the specs either will work on a 12" and center the cutting tool but the size of the shank on the cutting tools is larger on the BXA.

1/4 - 5/8 on the BXA and
3/16 - 1/2 on the AXA

 

[kvom]

On my 10EE the centerline is just less than 1.25" above the top of the compound, so pretty similar to yours. There is no issue with my AXA toolpost. The bottom of the holder with a 3/8" bit is over .25" above the compund., so there is also no problem using 1/2" tooling.

 

[shred]

Here's a BXA- and AXA-size QCTPs on the compound of a 12x36 (the AXA is just sitting there, not mounted)

At 'max height', the bottom of this AXA holder is at about 1" from the top of the compound, so it will work, but the BXA is a better "fit". FWIW, the "official" toolholders are quite a big bigger for the BXA size, but the cheap ones from CDCO are very similar to each other except for dovetail width.

 

[steamer]

Hi Marv,

My 12" Logan has an AXA wedge post of far eastern origins. Your comment about centerline height from the compound is a good observation. My Logan is an unusually low 1.00"

The AXA has been used to take 3/4" off diameter in mild steel at 300 rpm with .005" /rev feed. This with a 1/4" radius tool with little top rake.

I did not have a power meter on the lathe, but the 2HP 3phase motor was definitly working hard.

The toolpost is plenty rigid....the wedge type anyway. I can't speak to the piston type, but my suspicion is the piston type will not repeat as well or be as rigid...a bit of analysis will point out that the dovetail clearance never really goes away....

I can post a picture of the post set at 1.19" if it would be of value....to see how much vertical travel was remaining. I would do this with a max/min thickness tool.

Let me know.

Dave

 

[Paolo]

Hi Dave
It would be nice to see some pictures...
Best regards
Paolo

 

[ariz]

I would go with the BXA because it is much stronger and its toolholders take tools higher than the AXA

but I use more often tools with changeable carbide inserts (sandvik, iscar, etc.), that have usually a quite large/high shaft (~ 20 mm), while you mklotz do prefer to use HSS tools IIRC, which are of more manageable measure

 

[steamer]

So Marv, what did you decide on ?


Curious.....

 

[steamer]

Well anyway, your welcome.

 

[mklotz]

Gee, touchy. I didn't realize that there was a time limit on replying.

Thank you for your offer to help, Steamer. I appreciate it. To answer your question, I haven't decided yet what I will do. Frankly, I don't see that the QCTP provides that much advantage over my multiple three and four tool turrets. Yes, they all use shims but once set up the tools remain in place because there are so many turrets. All but one of the turrets is fitted with a integral wrench for mounting so swapping turrets is about the same effort as swapping tool holders on a QCTP.

 

[steamer]

Gee, touchy. I didn't realize that there was a time limit on replying.




?





Thank you for your offer to help, Steamer. I appreciate it. To answer your question, I haven't decided yet what I will do. Frankly, I don't see that the QCTP provides that much advantage over my multiple three and four tool turrets. Yes, they all use shims but once set up the tools remain in place because there are so many turrets. All but one of the turrets is fitted with a integral wrench for mounting so swapping turrets is about the same effort as swapping tool holders on a QCTP.

Great!