BXA holder in a AXA post?

[KyleG]

You can also use a standard toolholder like a V block and clamp round stock to it. That’s how I cross drilled a boring bar I made.

If you want to get fancy, you could tap some holes in the face of the holder to bolt a strap across the tube.

If you want to get extra fancy, you could bore a half-round into the toolholder for better support.

 

[Cadillac STS]

Could you just put a piece of metal on one side of the dovetail to take up the difference in size? 1/8 inch by 1/4 by 2 inch? Like a gib goes in a dovetail. Get it sized perfect then hold the strip in with a drop of super glue. Threat it like an axa after that.

 

[bulgie]

Name brand might be, but I bet imports aren't. I don't have a one to test though.

Good point, I ordered Aloris brand just out of my usual habit of avoiding Chinese knockoffs, but in this case cheaper might actually be better for the purpose!

 

[bulgie]

You can also use a standard toolholder like a V block and clamp round stock to it. That’s how I cross drilled a boring bar I made.

If you want to get fancy, you could tap some holes in the face of the holder to bolt a strap across the tube.

If you want to get extra fancy, you could bore a half-round into the toolholder for better support.

Yeah but in my case, I'm holding very thinwall tubing, as thin as .012 wall. It has to be held in a round holder or it distorts with very little pressure.

 

[bulgie]

Could you just put a piece of metal on one side of the dovetail to take up the difference in size? 1/8 inch by 1/4 by 2 inch? Like a gib goes in a dovetail. Get it sized perfect then hold the strip in with a drop of super glue. Threat it like an axa after that.

Exactly the question I was asking. That's what I pictured in my head when I wrote "shimming the dovetail", but I was wondering if anyone had actually tried it. I was thinking green loctite, but superglue might be perfect, thanks! I don't keep it handy in my shop, but I should.

 

[Cadillac STS]

Just to throw this out there…. I know you want to mount a holder in your QCTP and this is not that. Or maybe it could be mounted on the QCTP simply mounting a half inch bar on back of the chuck and put in a regular QCTP holder. Depends on length of tube needed. The chuck below has long jaws and may work.

A 6 jaw chuck can hold thin wall tube nicely because the pressure is spread among the 6 jaws. In this application a 6 jaw could be mounted to stand on the cross slide aligned to the right height to accept the tube. need to be sure the through hole is large enough but if the part is short it would not matter

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[WobblyHand]

An Aloris AXA tool holder may be hardened, but it milled off very nicely with a carbide end mill. I had an AXA 8 that would not adjust to center line, so I milled off 0.050" from the bottom. I encountered no issues with a carbide end mill.

I made a FreeCAD model of an AXA sized boring bar holder. It would just fit a 1" bar into it. Don't think you can fit 1.25" bar and meet center line. Actually I immediately take it back. It would fit, but you would have very little holding the bar. Think the AXA is 1.5" tall. So you would have 1/8" on each side. This assumes you want the holder on center line. Wouldn't be very rigid, but might be ok for your use. Boring out the hole would be fun with the interrupted cut. Might use a tough carbide insert in the beginning to cut through any hardened skin and use HSS to finish the bore.

 

[Chewy]

Here is a badly drawn picture. I used a square block for illustration. Rectangle would be better. Cut, file, mill one side to a tab that fits an AXA holder. Width some wheres a little more that 1/2". Thickness anywhere between 7/16-5/8" There is plenty adjustment in the screws and you can get an oversize 5/8" holder easily. The only criteria is that the screws dig in and hold securely. It does not matter within reason if it is a little crooked or whoppy-jawed as it will be corrected when you drill out the hole.
Mount the block in the tool holder and lock the height screw, bore out the hole. and all crookedness will be taken care of. Saw a slot in the side for clamping pressure.

Couple of points. If you ever plan on using this over, do the following. Orient the tool post to the chuck perfectly. use a 1-2-3 block up against the face. Mount the holder on the tool post all the way at the bottom. Do not use the height screws at all for adjustment. Hold the adapter up to the holder to get a general reference for locating the tab. The tab does not have to be in the center of the block. When you drill the hole using the chuck. the hole will be centered automatically for use. And straight. Give yourself about .002-3 clearence. You can now take this apart and store it. To use, clamp it in any holder bottomed out and orient the tool post to the angle you want to drill. Since the hole in the holder is perpendicular or parallel depending on your point of view to the tool holder, if you want a 30 degree angle, just use a 30 degree standard at the bottom of the tool post.

I have done this before in aluminum for quick holders. In the field I used a 2/4 in a vise to hold EMT. Just drill and clamp, no tab needed. No damage to the pipe either. I currently have collected about 20 lbs of cut up milk jugs. I plan to melt and make some square blocks and thick sheets for doing stuff like this. I'm cheap, why pay for 6061 when I can do plastic for free.

Just realized I oriented the block in the holder wrong in finished picture. That happens when you are get in a hurry.

 

[Chewy]

By the way, in going back through the posts, you said the tubing had ,012 wall thickness. I learned the 2X4 trick from plumbers about 60 years ago holding small pieces of copper plumbing for cutting and sanding. Never left a mark on anything. Of course you can always clamp it until it becomes oval.

Also, there is no reason that this holder has to be metal, Or a precision Aloris tool holder. I make a lot of stuff out of wood. I use chunks of oak and maple cut from fallen trees in my back yard. A maple or birch piece of wood with a nice smooth hole will work for your purpose and be easy to make. I like to think outside the box. I take what I'm doing and walk in circles around the shop and ask will this work. Hold the item up to wood, plastic, chunks of metal , PVC pipe, cardboard, etc. You will be surprised with your ideas.

 

[bulgie]

Here is a badly drawn picture. I used a square block for illustration. Rectangle would be better. Cut, file, mill one side to a tab that fits an AXA holder. Width some wheres a little more that 1/2". Thickness anywhere between 7/16-5/8" There is plenty adjustment in the screws and you can get an oversize 5/8" holder easily. The only criteria is that the screws dig in and hold securely. It does not matter within reason if it is a little crooked or whoppy-jawed as it will be corrected when you drill out the hole.
Mount the block in the tool holder and lock the height screw, bore out the hole. and all crookedness will be taken care of. Saw a slot in the side for clamping pressure.

Couple of points. If you ever plan on using this over, do the following. Orient the tool post to the chuck perfectly. use a 1-2-3 block up against the face. Mount the holder on the tool post all the way at the bottom. Do not use the height screws at all for adjustment. Hold the adapter up to the holder to get a general reference for locating the tab. The tab does not have to be in the center of the block. When you drill the hole using the chuck. the hole will be centered automatically for use. And straight. Give yourself about .002-3 clearence. You can now take this apart and store it. To use, clamp it in any holder bottomed out and orient the tool post to the angle you want to drill. Since the hole in the holder is perpendicular or parallel depending on your point of view to the tool holder, if you want a 30 degree angle, just use a 30 degree standard at the bottom of the tool post.

I have done this before in aluminum for quick holders. In the field I used a 2/4 in a vise to hold EMT. Just drill and clamp, no tab needed. No damage to the pipe either. I currently have collected about 20 lbs of cut up milk jugs. I plan to melt and make some square blocks and thick sheets for doing stuff like this. I'm cheap, why pay for 6061 when I can do plastic for free.

Just realized I oriented the block in the holder wrong in finished picture. That happens when you are get in a hurry.

Chewy, thanks for taking the time to draw and explain, I see now, that would work.

Making the part that goes into the slot in the AXA-1 holder is best done on a milling machine. For me it would be a hacksaw and file, tedious and not so precise. Plus then you have more sideways offset away from the toolpost, compared to mounting my holder directly to the dovetail, no AXA-1 in between the work and the post. My little lathe isn't very rigid so it needs all the help it can get.

Rigidity does matter when notching thinwall tube with a holesaw. There is a point partway through the cut where the geometry of the tube meeting the holesaw teeth makes the tube want to deflect down into the gullet between two teeth, causing the saw to grab and rip the tube. It can blow up the holesaw too. Fine-tooth holesaws help, but so does a rigid setup. I feed the Z by hand because I can feel when I'm in the danger zone and slow down the feed until I'm past the point where it tends to catch.

I have ordered the AXA-41D that holds a 1" tube, which I do need to notch, so I can test out the concept to make sure it's all great with 1". If so, then I'll just order the BXA-41D and see for myself if it'll attach to my AXA post. I think it probably will, with a shim, and it'll be the easiest way to get where I'm going. I'll update this thread with my results in case anyone else has the same question.

Thanks all!
-Mark B