# Dremel tool spindle thread size?



## dicej32

I made a milling column for my taig lathe which uses a dremel tool. I need to know what the thread size is for the spindle. I want to make a few accesories but would rather screw them onto the spindle than use the collet. Any help would be appreciated.

Thanks,

Jenaro


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## rake60

Jenaro I just measured it up.

It appears to be a 7mm X 1.0 thread, however I do not have a 7mm X 1.0 tap die or screw to 
confirm that. Perhaps someone else here can.

Rick


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## jgarrett

I bought a Dremel chuck to make a small drill adapter a while back and I remember the thread size was 48 tpi but don't remember the major dia. Not good enough at the math to figure out what 48tpi is to 1.0mm thread.
Julian G.


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## DickDastardly40

This is a quite recent addition to our arsenal, being cordless etc, but I don't believe they will have changed around with the business end too much, so hopefully still the same size.

The pitch looks to be 40 TPI, my metric gauges won't touch it nor will 1.0mm, looks adjacent to 60 deg included angle. 






Diameters in both flavours closest whole size is 7.00mm so a bit of a bastard being metric OD and imperial pitch









I think 1.0mm pitch will equate to 25.4TPI

Al


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## rake60

A second attempt at measuring the pitch without thread gages come a little
closer to .75mm That would be .004" per thread wider than a 40TPI pitch.
Over the length of a thread gage that would be visible. 

It is also possibly a propitiatory thread size specific to Dremel.
None of my measurements work out to any standard thread.

Rick


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## shred

I did some searching around a few months ago because I was going to make an adapter for it, but have since lost the key information-- as I remember it was some funky thread. Frank Ford has a bit on machining a tap for the 'big' thread (along with a ton of other cool info)-- the one that holds the collar on: http://www.frets.com/FRETSPages/Machining/Projects/19mmTap/19mmtap.html

update: on the Alisam site, they sell Dremel toolpost adapters in "3/4-12 or 3/4-16, measure first".. eek.


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## dicej32

Thank's for all the responses. I may just go ahead with the collet since it's not really worth the trouble to get a tap if it even exists.


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## georgeseal

The tread is propitiatory

.276 X 40

if we just have to make this thread we take a 1/4 X 40 tap and run it through( hole is now .026 to small .016 on each side of hole.
find a wire that will almost fit in one of the flutes. back the tap out , slide wire in & tap again. Keep doing this with larger wires or two wires and sneak up on your shaft. This will work for one of, more than that make a tap.

This tip will also work on dies that cut a little large

Well that's all from the peanut gallery for now

George from Conyers Ga.
Edited because I got my figures wrong. I am old enough to make mistakes not Bads


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## Shadow

.275 x 40 is a standard thread size for 8 mm watchmaker's collets. I checked by threading a dremel chuck onto a Sherline made chuck adapter and it threaded on. A tap and die can be found on eBay usually under the watchmaker's sections. An article in home shop machinist some years ago for a micro drill press listed this as the thread size the author used.


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## rake60

How about this...

Mine mics .278" on the OD of the thread.
It does look to be 40TPI.

9/32" is a nominal .281"
*Hobby Mechanics* lists 9/32-40 taps and dies on their web site....

Could it be?

Rick


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## mklotz

When I made this pin vise...






I single-pointed a 40 tpi thread and the three jaw chuck sold by MicroMark fit perfectly.


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## Shadow

Thread size for the metal output shaft is .28 X 40 threads per inch.

If we can assist further please let us know. Email or call Dremel customer service with questions at 800-437-3635.


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## crankshafter

hello everybody in the"imperial" part of the world :'(
 Spindlenose threads on Dremels are for sure 8mm x o.75 pitch

And I will wish you all a happy New Year ;D


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## Toble928

I think it's 9/32" x 40 TPI.

Tony Blewett, UK


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