AXA Tool Holder(s)

[Janger]

Craig I had this explained to me by dabbler. You put two dowel pins into the dove tail slots one at each end and measure the distance between them. That will give you a measurement you can then aim for with the one you are making. I think there is a calculation to determine the distance from the pin into the corner … that’s not coming to mind right now. Try this anyway I think it will get you there.

 

[Susquatch]

I think there is a calculation to determine the distance from the pin into the corner …

I don't think so. You would have to precisely know the angle of the sides to calculate the pin to corner distance.

 

[140mower]

When I did mine, I took out the middle section first to full depth using a depth mike to be sure, and within .005" on the width, then did the dove tails, stepping over every .010" and hand feeding the down feed until I almost reached the top, leaving about .020" landing at the top. Then I flipped my tool over for the other side and repeated. I set up a dial indicator once I started getting close..... I wish my slabs had been a little longer, as I only got three per setup, six would have been nice, but my junk pile doesn't support all my wants, only most of my needs.
You might want to get a little sharper angle on your tool with a nice sharp tip to reduce the chatter some.....

 

[YYCHM]

Sort of like watching a power hacksaw. I drag mine out every now and then just to watch it work. LOL

Ya, I have one of those to. Love it. If I don't box it in, it wanders all over the basement floor LOL. Don't use it much after getting the bandsaw though.

 

[jcdammeyer]

Ya, I have one of those to. Love it. If I don't box it in, it wanders all over the basement floor LOL. Don't use it much after getting the bandsaw though.

I sold my Gingery Hacks and Slip roll after I bought a used bandsaw and the 3:1 tool. I must admit I make more boxes now with the 3D printer than I do with the shear and brake.

I went down and checked and the only dove tail cutter I have is 1/2" x 45 degrees. I held it up against one of the AXA tool holders and it's clearly not 45 degrees plus this one is too small anyway. But it might just work to make a smaller sub AXA size with a piston type mechanism.

 

[jcdammeyer]

Are you guys trying to say the dovetail depth (D) has to be within a tolerance (as well as distance between dowel pins of course)? Dimension B is a bad reference for practical machinists IMO.

Perhaps check my math here. Assuming A and B are correct for the ASA tool holder then (A-B)/2=Adjacent side while D is the Opposite side so arctan(Opp/Adj) = dovetail angle.
(1.64-1.37)/2=0.135" and D=0.383" so ArcTan(0.383/0.135)=70.58 degrees. Somehow that strikes me as wrong? You'd think they would make that angle 60 degrees.

 

[Tom Kitta]

Wow, you guys make me look like master machinist. My AXA fit very snug, all 3 of them - but I doubt I could do them as well on a shaper - the mill is my ticket.

The pin method is not hard at all - just use 2 pins, place them in known good AXA. measure precisely the distance. Then measure the depth - how deep you square EM needs to get. Then how narrow is the opening.

First cut the depth, then the opening. Now you have a square block with a rectangle cut in it.

Now with a dovetail cutter touch on each side and for the depth. Put all in DRO. Now start cutting same amount per side, both sides. Exactly the same.

Now measure with two pins. Note how far off you are. Cut exactly that.

Now you made a part that is like +-0.002 off the original AXA.

On a shaper, without a DRO this is much more difficult. I guess I would try to do the same, but you need to play a LOT with the dials.

On related note, would DRO be of any use on a shaper? I have some extra scales.

 

[RobinHood]

Are you guys trying to say the dovetail depth (D) has to be within a tolerance (as well as distance between dowel pins of course)?

Yes, absolutely!

Here is an illustration to explain why.

In both cases the distance between the pins is equal. The one on the left has a shallower D distance. The D dimension on the right is larger. Since the wedge pulls the holder against the tool post, D is important since it is defining the second reference surface.

Craig, looks like your dovetail angle is off a bit as well.


I would measure the tool post across pins. Set the wedge about 1/2 of it’s travel. Then use a calculator like this http://www.machinist-calculator.com/Dovetail-calculations.html to determine the distance across the same pins of the holder. After you have the holder fitting, just open the base and one side a bit for better operability.

 

[jcdammeyer]

Wow, you guys make me look like master machinist. My AXA fit very snug, all 3 of them - but I doubt I could do them as well on a shaper - the mill is my ticket.

What angle dovetail cutter did you use?

 

[PeterT]

RH>Yes, absolutely!
That's what I figured. Need to pay attention to tool post dimension D

I was going to draw up Craig's pin diameters to get the distance, but better yet, the dovetail web app you linked has everything there.

 

[YYCHM]

The Shars website publishes this...

H 0.386
L1 1.687
L2 1.382

I'm beginning to doubt that what I have is actually 60 deg. I'll try @RobinHood's website with some end mill shanks as pins tomorrow.

 

[PeterT]

Perhaps check my math here. Assuming A and B are correct for the ASA tool holder then (A-B)/2=Adjacent side while D is the Opposite side so arctan(Opp/Adj) = dovetail angle.
(1.64-1.37)/2=0.135" and D=0.383" so ArcTan(0.383/0.135)=70.58 degrees. Somehow that strikes me as wrong? You'd think they would make that angle 60 degrees.

Right you are. WTF.
I know we have discussed this before. I just cant recall what the conclusion was. Error in drawing? Custom tool holder? Maybe this explains some of the fit / no fit issues

 

[jcdammeyer]

Right you are. WTF.
I know we have discussed this before. I just cant recall what the conclusion was. Error in drawing? Custom tool holder? Maybe this explains some of the fit / no fit issues

I'm going to guess just like the shars drawing that these are all sketches and not mechanical design drawings. So the dimensions are approximate without taking into account corner radius or bevel.

 

[PeterT]

Agree. One stands a slightly better chance with the theoretical point to point diagram of the Aloris/Dorian sketch, just leaving the radius which probably isn't too critical give the generous chamfer of the TP male. . The Shars diagram is messed up, bad dimensioning practice.

Back to the angle discrepency, I have seen plenty of references to 60-deg Aloris, so something is not right. Is the chart in error? If it was a special angle that precluded common commercial cutters I could see it as an attempt to keep buying the compatible brand. But seems like people swap them on & off with other systems all the time & are predominantly 60-deg?

I got the pic from here

Precise 6 Piece Quick Change Tool Post Sets

Offering a huge selection of industrial tool sales online. Find over 100,000 metalworking products, precision measuring tools, power tools & accessories.

www.penntoolco.com

 

[Six O Two]

Using PeterT's linked dimensions, the theoretical opening with no radius is 1.198", assuming 60deg dovetails. Shars' numbers seem... fishy

 

[jcdammeyer]

Using PeterT's linked dimensions, the theoritical opening with no radius is 1.198", assuming 60deg dovetails. Shars' numbers seem... fishy

On this drawing the math works out to 60 degrees.

 

[Tom Kitta]

God maybe I just make a video of doing this. Its not that hard. Well, maybe on the shaper it is hard. You guys are totally over thinking this. Totally.
First of all did I say get dimensions of the web? NO. I measured known tool holder and sticked to that measurement. My tool holders will almost 95% not fit Shars tool post. But they fit mine like a glove. I have Armstrong and it is same size as Aloris (or very close) and my AXA will not fit much wider Shars. Part of the reason I would not buy expensive tool holders from say Accusize - they rattle and are too big. But at say $10 a pop I can be convinced - sure they fit like crap but they were more or less free.

 

[Susquatch]

Silly question @YYCHM .

Why not cut the dovetail on your mill instead of on your shaper?

 

[Aliva]

This video may give you some tips. Pierre from Montreal

 

[PeterT]

Yup, one of many examples stating Dorian or Aloris TP with 60-deg dovetails. That would infer dimension diagram in PennTool link is bogus.