Accurate Tap Guide using an ER32 collet chuck

[More4dan]

I've had an issue with some specialty taps I ordered in a group buy a while back. They didn't have the 60 degree hole nor a point in the end to use a tap guide. So I modified a design for holding dies to an ER32 collet chuck with a straight shaft. Here is what I came up with.

I reused my LMS MT2 shaft from their die guide. This required me to make a sleeve for the collet chuck to fit the ID of the shaft and the OD of the die guide shaft.

It works extremely well. I just locked the headstock and spun the chuck by hand quickly threading a piece of Acrylic. You could also use the motor on slow holding the chuck loosely and let go when feeling too much resistance. It works just like threading with a die.
No more advancing the handwheel on the tail stock while spinning the headstock and holding on to a tap wrench all at the same time.

The ER32 chuck was $22 from here: https://www.banggood.com/ER16ER20ER...9.html?rmmds=search&ID=46421&cur_warehouse=CN

i did cut about an inch off the chuck shaft to match the length of the LMS shaft.

If you don't have a die guide, another option is to make a die holder (or get Rick to make one) that would be held in a 20mm collet so I could use this same tool for taps and dies. Also would have to make a guide shaft with a MT2 taper.

Hope you find this useful,

Danny

 

[magpens]

Get it ... except where you say ...

"I reused my LMS MT2 shaft from their die guide. This required me to make a sleeve for the collet chuck to fit the ID of the shaft and the OD of the die guide shaft. "

I see your thumb on the collet chuck ... and I see the LMS MT2 shaft from their die guide on the right ... but the piece in-between (gun metal color) to which your baby finger is pointing, did you make that ? (And is that the whole point ?)

 

[More4dan]

The guide shaft that sits in the tail stock was borrowed from my die guide I purchased from LMS. The OD of the shaft is just under 9/16". The hole in the shaft of the collet chuck has an ID of just under 1". I turned a 3" long piece of aluminum to match the collet chuck Shaft ID and drilled it 9/16" to match the guide shaft. I could have made a new guide shaft to match the collet chuck but that would have required me to machine a MT2 taper. Also the ID of the collet chuck was pretty rough so the sleeve I made gave me a smoother fit.

You can see the sleeve in the bottom of the last photo.

(Pinky pointing) That is the straight shaft that is part of the Collet Chuck. It's machined from a single piece of metal.

The only thing I had to make is the internal sleeve.

Danny


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[More4dan]

Here is what the Collet Chuck looks like.

 

[magpens]

Danny wrote: "The only thing I had to make is the internal sleeve. "

Oh, OK. I get it. ... Thank you very much for everything above ! . I think this is a very helpful thread. . Thanks for taking time to write/post it.
I now feel comfortable that I know exactly what is going on.

When I am in that situation (tapping a centered hole) I grip my tap in a Jacobs chuck mounted LOOSELY in the tailstock (not anchored down).
I know this is not an accurate way to do things, but if you are extremely careful it can work.
I then rotate the head stock chuck (workpiece gripped in that) with my left hand. . With my right hand I lightly grasp the Jacobs chuck with tap and guide it in the direction of the work piece (the tap and Jacobs chuck will get pulled in that direction, pulled away, now looser in the MT2 tail stock).
Depending on what my objectives are, I might advance the tailstock a tiny amount towards the headstock.
I hope you get the gist of this.

The sliding LMS die holder (shown in your 4th picture) is a great way to hold a DIE accurately, but with your method, we now know how to do similarly with a TAP mounted in a ER-32 collet chuck !! . I think I even have such a collet chuck and will be using it like this in future ! . First I need to make the required sleeve just as you did.

 

[magpens]

@More4dan

I might just suggest, for greater clarity, that you edit your sentence:

"This required me to make a sleeve for the collet chuck to fit the ID of the shaft and the OD of the die guide shaft. "

to read:

"This required me to make a sleeve to match the ID of the collet chuck tail to the OD of the LMS die guide shaft (shown in tail stock)."

I hope you don't mind me making that suggestion. . I am an old f**t and sometimes need some "crutches" with the language !

 

[More4dan]

Thanks for helping me clarify my madness and methods.
I've done the Jacobs chuck dance myself. This worked much better.


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[Ironwood]

Thanks for taking the time to post this Dan.
This is better than how I have been doing it so far, my method is the same as Mals, I think.

 

[guitarchitect]

I think I'm going to try this! Can I ask - how did you lop the inch off the collet chuck shaft? I haven't really got any metalworking stuff to speak of, other than a dremel with a cutting wheel and a hack saw I'm guessing it's probably too tough for both.

 

[howsitwork]

Danny that's a really great idea . Thanks for sharing it.

 

[duncsuss]

I think I'm going to try this! Can I ask - how did you lop the inch off the collet chuck shaft? I haven't really got any metalworking stuff to speak of, other than a dremel with a cutting wheel and a hack saw I'm guessing it's probably too tough for both.

I bought one and asked Rick Herrell for help. He rebored it and make a mandrel it would slide on. Very happy with the outcome.