# Tap Follower



## KyleG (Sep 21, 2021)

My 3/8 round bar showed up last week, so this weekend's project was a tap follower. Starting stock was 3/4 and 3/8 1144 Stressproof bar.




First, I turned the #2 Morse taper. It took a couple tries, but I eventually got a fit that I was happy with. Fortunately, tweaking the taper doesn't mean scrapping the part, it just pushes a little further up the bar. After that, it was drilled to .406 and tapped 7/16-20.





At this point, the full 3' bar is through the headstock. Move it out, part it off, and then into the headstock goes the part. It was pretty trippy to fixture a part by just sticking it in the headstock. In this setup, I faced the part, chamfered it, and drilled the .250 thru hole. Unfortunately, I don't have a .250 reamer, but it came out well anyway.




Up next was the pin. First operation was to point the stock to 60 degrees. Next it needed to be turned to .250 OD, but I don't have an inverted center. Conveniently, I have a bunch of endmills that do though! Ta-da, improvised dead center! I was pretty proud of myself for thinking of that, and I hope it helps someone in the future.




I didn't take any photos of the retaining screw, but it's nothing special. Here are some photos of the finished product:










All in all, it was a fun, successful project and I learned a lot along the way. If there's interest, I can post the files or prints of the design.

Thanks for reading!
-Kyle


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## Brento (Sep 21, 2021)

I am interested! My mill and lathe are both MT2 so i could use this like crazy.


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## extropic (Sep 22, 2021)

@KyleG 

In your design graphic, does the orangeish part represent the spring at full compression?


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## KyleG (Sep 22, 2021)

extropic said:


> In your design graphic, does the orangeish part represent the spring at full compression?


Yep


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## Brento (Sep 22, 2021)

@KyleG i would love your drawings


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## KyleG (Sep 22, 2021)

After some adjustments to represent the erm.... "as-built" configuration, here are the prints and CAD model.


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## Brento (Sep 22, 2021)

Thank you!


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## brino (Sep 23, 2021)

Great work @KyleG!
....and thanks for sharing the drawings.



-brino


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## Brento (Sep 23, 2021)

You designed  it but is there enough space to get a 3/8 thread in the cap?


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## rwm (Sep 23, 2021)

Simple and elegant.
Robert


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## KyleG (Sep 23, 2021)

Brento said:


> You designed it but is there enough space to get a 3/8 thread in the cap?



Do you mean in the back of the retaining screw, like for a drawbar?


Sent from my iPhone using Tapatalk


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## Brento (Sep 23, 2021)

Yes sir!


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## KyleG (Sep 23, 2021)

How deep of a thread do you need for the drawbar? I have an idea brewing...


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## Brento (Sep 23, 2021)

Well since it would be to just pull it in prob not much but my draw bar is a nut and acorn nut. I use the acorn nut to engage whatever is in the spindle and then use the nut to tighten down.


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## extropic (Sep 23, 2021)

Brento said:


> Well since it would be to just pull it in prob not much but my draw bar is a nut and acorn nut. I use the acorn nut to engage whatever is in the spindle and then use the nut to tighten down.



Unless your MT2 taper is in poor condition, the tap follower (with an accurate MT2 shank) will stick plenty well without a draw bar.
If you have other purposes for the TF, YMMV.
If you intend to use it as spring loaded follower, you're worried about a nonexistent problem.
After all, the thing is always spring loaded into the socket while in use. The spindle isn't even turning when using a TF.
If your MT2 taper is in poor condition, it needs fixing before any more tools are inserted.
If you think anything I've said above is false, please tell us what you intend to do with the TF (or modified TF).


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## Brento (Sep 23, 2021)

You right i dont really need it. I guess i would want the thread just to have it? But my spindle is pretty good.


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## KyleG (Sep 23, 2021)

I agree with @extropic that it's unnecessary, but it was still a good design puzzle  Here's how I'd make one to interface with the drawbar. The only use for the drawbar that I do see is ejecting the follower.


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## Brento (Sep 23, 2021)

I kinda like that design better. As you guys said. I do agree that it is not needed but id rather have like threads if possible for my taper tools. Better safe then sorry. So did you make everything the same as the other except change the thread and the capture screw? Where dis you end up getting your springs?


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## KyleG (Sep 23, 2021)

I had to reduce the thread size from 7/16-20 to 3/8-16 (which I assume your drawbar is), which meant reducing the diameter of the bore, the head on the pin, and the spring. I picked the spring out of an assortment I bought on Amazon. Having a spring assortment has been really handy. For the one in the graphic above, I have McMaster 94105A603 penciled in, but I might change my mind. I'll run an updated set of prints in the next few days.

One thing to note, if you want to use this on your lathe as well, you'll probably want a removable screw so it ejects from the tailstock. I doubt it will as-is. I'll add one to the model and drawing.


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## Brento (Sep 23, 2021)

When you get around to it id love a copy. I will for sure have to add a stud to the back to eject it. I have a ER20 collet holder with a MT2 shank and it is a M10 thread bc i didnt pay attention. So im going to make that my lathe collet holder so i can use it for endmills or something. Who knows. But i have to do the same thing. I need to make a stud in the back to eject it. I just need to figure out how far i need to go to eject it.


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## KyleG (Sep 25, 2021)

Drawings for the drawbar variant attached.


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## Brento (Sep 25, 2021)

Im loving that thank you. Im not seeing a huge difference in it all so i will decide farther when i make it but i may go with the drawbar version and just make an extension plug for the lathe.


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## KyleG (Sep 26, 2021)

Brento said:


> Im loving that thank you. Im not seeing a huge difference in it all so i will decide farther when i make it but i may go with the drawbar version and just make an extension plug for the lathe.



Glad to be of service. In your shoes, that's what I'd do.


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## Brento (Sep 26, 2021)

I find its always nice to have stuff to fit your machines even if you dont need it.


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## rwm (Sep 26, 2021)

I need a very short tap follower to use on the Mill and DP. This has inspired me to make one. 
Thanks
Robert


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## Ken226 (Sep 28, 2021)

I made one this morning.  I went with a 5/8" shank so I could use it in collets, end mill holders or drill chucks. It's only got 1.5" of plunger travel, but will work for most of my tapping jobs.


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