Gary, after doing a Google search, it's 3/4-12. I have one, and the tools to check myself, but thought it would be quicker to just Google that info. And unfortunately, the nominal size (sizes you will find at hardware stores) are 3/4-10 National Course or 3/4-16 National fine. So you will more and likely have to have a machine shop make you one that is 3/4-12. Not hard to do. Probably cost the minimum a shop charges in your area. I could probably have one made for around 50 bucks, here. If I had a lathe, I could even make one myself. ;o)

 

If Wikipedia is to be believed, the 3/4" size of British Standard Fine (BSF) thread is 12TPI. Apparently BSF thread taps are still available. Whether the thread form is sufficiently similar is another question of course.

 

Another possibility and probably one that I would use in the absence of a suitable tap would be to rout a hole in the panel, square, round, it doesn't matter, also a rebate, similar to fitting a router table plate. Into the hole fit a metal plate, steel, brass, aluminium, whatever, and hold the the plate in the rebate with a small countersunk screw in each corner. The plate will have a 3/4" clearance hole and the Dremel poked through the hole and held in place with the housing cap. Problem solved!

 

This Shop Dremel Rotary Cutting Kit at Lowes.com would give you a threaded collar that you might be able to use.

 

Thanks everyone!

 

I realize this is an older thread but I have made dremel attachments using a 3/8 npt pipe tap. it is not an exact fit but given the short thread length threads in fine and has not damaged the plastic threads on my dremel. The 3/8 npt is .075" smaller than than the 3/4" dremel thread but snugs and squares up if threaded in to the shoulder of the threaded portion. I hope someone can use this info.

 

I have an old spindle mount for a 42mm nose router, so I 3D printed a split collar with a 3/4 12 thread inside. I used PETG but ABS would have been almost as good. So I can screw on the collar and clamp the Rotary Tool in the mount held in a vice. The added bonus is that the spindle mount has LED lights.

 

Hi and welcome Kent. Nice to have you aboard.

 

Welcome to the forum, @kent

 

thank you, i look forward to participating

 

FYI:
DREMEL mototool nose is 3/4" x 12 tpi and the spindle thread is 9/32" x 40 tpi (for collet NUT)
Collet size is usually 1/8". (usually because mine has 5 collets of 4 different sizes (2 of 7/64", 1 of 1/8", 1 of 3/32" and 1 of 1/16") and a variable 3-jaw drill chuck).
Mine can control motor Speed in 5 steps from 5,000 to 30,000 RPM

(Not a router since motor and chuck is only connected by a plasric tube by friction)

 

I bought a 3/4-12 tap years ago so I could fabricate my own adapters and fixtures.

 

Welcome to the forum @Cropwell

 

G'day from Australia, @Cropwell , welcome to the forum.