PDA

View Full Version : Fit a BXA Tool Post



bstarling
06-30-2011, 10:14 PM
I've had my HF 12x36 for a while now and have found it to be a very nice lathe. It's day and night between it and my little 7x14. The one thing I was missing though is the QCTP on the 7x. I got a new BXA QCTP for the 12x and am now trying to mount it. I think the deal is to mill or turn the BXA base to fit the 12x compound slot, but am wanting to get a second or even third opinion before I screw up my nice new BXA tool post. The baseyblank that came with the BXA is a considerable chunk of steel and the one on the lathe is substantially smaller.

Anyone done this? Please help.

Bill

Duffy
06-30-2011, 10:59 PM
I fitted one to my Standard Modern. I ignored the supplied block and milled a T-nut to fit the compound slot, tapped it for the center bolt and it worked just fine. I imagine you need a bit of 1/2" x 1" steel bar, about two inches. I think that the bolt was a 1/2" fine thread.

JoeLee
06-30-2011, 10:59 PM
That is the thought with the blank that Aloris provides with the tool post. I think they give you a big blank to start off with since the BXA may be used on larger machines with bigger slots in the compound. You could always make one and save the original blank incase you have to enlarge the slot in the compound.

JL..............

form_change
06-30-2011, 11:02 PM
Not sure I understand what you are asking 100%, but you don't machine the tool post. The lump of material that came with the tool post that looks like a square nut is the thing that gets machined.
If you go here -
http://www.aloris.com/catalog/aloris_p2-3.pdf
it sort of illustrates that on the bottom of the second page (page 3).
You can either pin the post to the nut to prevent rotation or leave it clamped up but with no pin so that it can be swung to other angles. That in itself is a discussion point (see the thread "Why do QCTP's have only one handle?")

Michael

bstarling
06-30-2011, 11:10 PM
Not sure I understand what you are asking 100%, but you don't machine the tool post. The lump of material that came with the tool post that looks like a square nut is the thing that gets machined.
If you go here -
http://www.aloris.com/catalog/aloris_p2-3.pdf
it sort of illustrates that on the bottom of the second page (page 3).
You can either pin the post to the nut to prevent rotation or leave it clamped up but with no pin so that it can be swung to other angles. That in itself is a discussion point (see the thread "Why do QCTP's have only one handle?")

Michael

Thanks all for the replies.

This lump is 1.6" x 1.8" and 0.650" thick. I am thinking this maybe a blank for machining since the center bolt on the post does not extend below this piece.

Bill

Highpower
07-01-2011, 06:45 AM
This lump is 1.6" x 1.8" and 0.650" thick. I am thinking this maybe a blank for machining since the center bolt on the post does not extend below this piece.

BillExactly. I bought both an AXA and BXA tool post for my 12x36, and had to mill BOTH of the "T-nuts" to get them to fit the cross slide. The good news is, you only have to do it once. ;)

Davo J
07-01-2011, 08:53 AM
Thanks all for the replies.

This lump is 1.6" x 1.8" and 0.650" thick. I am thinking this maybe a blank for machining since the center bolt on the post does not extend below this piece.

Bill

Hi Bill,
In the link below is a great right up and a step by step process of fitting a BXA tool post to a 12 x 36 lathe with a lot of pictures as well.
I am not sure if you have to join to see the pictures, but if your looking for help with one of these lathes it would be worth while joining as the whole thread is about buying a new 12 x 36 lathe, setting it up and doing some modifications to it.
The part about fitting the tool post is from post 153 on, but as I said the whole thread would be worth a read.
http://www.candlepowerforums.com/vb/showthread.php?216408-my-new-lathe-...-Precision-Matthews-12x36-.../page6

Dave

bstarling
07-01-2011, 10:56 AM
Thanks to all for the help. Dave, that link was outstanding. I've been wanting to find a site like that and haven't run across it to you helped out. :) Now I have to get my mill going and take about a pound of steel off of that chunk. The dang thing is only a machined rectangle so there is quite a bit of extra metal.

Bill:)

garyphansen
07-01-2011, 11:27 AM
I have machined around 50 of these in a lathe. No milling machine required. There is no reason to make it like a "T" nut. You can turn the "Leg" of the "T" round or even just make the nut square and leave the "Leg" of the "T" off all together. I always made the nut fit the slot so that it would just slide easily and not tight or loose. Gary P. Hansen

Steve Steven
07-01-2011, 11:29 AM
Its POSSIBLE to do all the machining in the lathe, but a mill is MUCH better. You can thin the width down by standing the blank up in the 4-jaw, machine down to mark and repeat, then chuck flat and turn down to fit the slot similiar to the one provided (at least with my HF 12X36).

Steve

bstarling
07-01-2011, 07:40 PM
Gary, Steve, thanks for the info.

Actually, the T-nut on my HF is round and could be made easily on a lathe. I guess I'm a glutton for punishment so I'm in the process of milling (slowly) the rectangular base that came with the tool post. It's rather painful using my mill/drill. It needs pretty light cuts and is not so easy to set up and gauge quill depth with. I think one of my projects soon will be to put some sort of digital read out one the quill. That will be for another day.

Bill

noah katz
07-01-2011, 08:01 PM
Now I have to get my mill going and take about a pound of steel off of that chunk. The dang thing is only a machined rectangle so there is quite a bit of extra metal.

If you've got a band saw you could cut out two rectangles