Author Topic: Tailstock tap/die holder  (Read 1654 times)

Offline PekkaNF

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Tailstock tap/die holder
« on: December 16, 2017, 09:02:47 AM »
Gobled together small tapping holder.

MT3 blank arbor has 12H7 reamed hole.

ER11 OD12mm collet shank fit into MT holder pretty nicely. Easy sling fit. Planning to use it for under M4 taps. Planning to turn a small knurled aluminium collar to it.

Then udes some 12 mm nominal shaft and turned 9,6 mm OD to it. THere is going to be a 3/8"-24 UNF thread for drill chuck. Planning to use to open holes for tapping.

Next thing is to make a small holder for 16 and 25 mm dies. I don't have any plans yet. Some questions:

Even small die needs some torque. Seen many with stick out on the side. Do not like it. Key or dog clutch?

Pekka

Offline chipenter

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Re: Tailstock tap/die holder
« Reply #1 on: December 17, 2017, 03:23:17 AM »
The stick is handy for resting on the tool post for large threads , I remove it for small treads and just grip the body , I may get round to putting on a knurl one day .
Jeff

Offline PekkaNF

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Re: Tailstock tap/die holder
« Reply #2 on: December 17, 2017, 02:54:26 PM »
Had splitting headache - used that time cleaning house.

Felt better two hours ago and made it into garage. Second part turned out right, first was exactly one millimeter too big on spigot.

Threrapeutical really. This is for small taps. 2,5 mm tap as a scale and the thread die OD is 16 mm.

Bigger tap is short M12 tap to give some scale.

M4 crub screws are way too long, they are thre just to check the fit. Need to get shorter cone point set screws.

Pekka

Offline JHovel

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Re: Tailstock tap/die holder
« Reply #3 on: December 19, 2017, 03:00:42 AM »
Looking good, Pekka!
I'd be a worried about the proximity of the grub screws to the knurled hand grip though! Either much shorter grub screws or a bigger diameter knurled section for safe hand hold.... or both.
Cheers,
Joe

Offline PekkaNF

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Re: Tailstock tap/die holder
« Reply #4 on: December 19, 2017, 05:35:12 AM »
Thank you

Looking good, Pekka!
I'd be a worried about the proximity of the grub screws to the knurled hand grip though! Either much shorter grub screws or a bigger diameter knurled section for safe hand hold.... or both.

That's what I thought I said...They are just as a placeholder and to check that I tapped them right....would have been a bit silly to tap for wrong thread.
M4 crub screws are way too long, they are thre just to check the fit. Need to get shorter cone point set screws.

Need a new knurls and knurling holder, these don't look too great. Did not want to push parts too hard.

I am still a bit undecided for the next bigger size construction. Really thinking of a dog clutch type to allow short thread formation and then sleeve (with tap or die) to spin freely when set thread distance is reached. Bit like this:


Pekka

Offline PekkaNF

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Re: Tailstock tap/die holder
« Reply #5 on: December 19, 2017, 03:34:07 PM »
Got drill chuck at the end of the shank. 3/8-24 imperialistic thread...

Now, few small projects and maybe a bigger die holder.

Pekka

Offline JHovel

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Re: Tailstock tap/die holder
« Reply #6 on: December 21, 2017, 03:22:31 AM »
Sorry, Pekka, overlooked that comment about thread testing with longer screws....  :doh:
I really like the releasing die holder you linked to. I had not seen that before.
Looking forward to your implementation!
Cheers,
Joe

Offline PekkaNF

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Re: Tailstock tap/die holder
« Reply #7 on: December 21, 2017, 03:53:56 AM »
No problem...your comment about the protrudig screw is valid on work safety point of view and well worth extra words.

My initial plan was to go with reckless abandon....but daughter needed to make a review about movie and she chose Inglourious Basterds - we had a long chat and exhange of opions....she was typing her work on the net at the other side of the kitchen table and I were "planning" the release type die/tap holder. Design came four pages long with all the scrible and notes. I think I have a viable design.

The idea is simplified dog clutch. Total stroke in order of 35 to 40 mm, which can be limited shorter with a positive stop. The idea is to use tail stock screw to engage die/tap and use a stop to set engagement (threading) length.

Pekka