Thread: using larger end mill

With a threaded end, that would be designed to be used with a collet chuck made for them, like a Clarkson. Or, a simple holder such as is popular in the US, which is just has a hole and a grubscrew. They both should be available in MT3.
Jordan

Probably your cheapest way out of it would be to Turn up an adaptor to suit the OD of the End Mill and the ID of the Collet.

For a positive drive you could either,put a flat on the End Mill so that a Grub Screw can locate against.

You could if this is going to be a purpose made adaptor, make the Bore .0005" to .001" undersize and heat and shrink onto the OD of the End Mill,I would still have the Flat and Grub Screw.

If you dont make it interference I would Drill,Bore and Ream the Bore.

I would machine the Bore 1st and then either turn the OD for the Collet in the same setup,or if doing it in 2 setups use a 4 Jaw when setting up for the Collet OD,

If you make it in ! set up and partoff the 3 jaw would be fine,but dont use the 3 Jaw if it is a 2 part opperation.

You could make a end mill holder for it like the one in this link half way down the page.
http://www.micro-machine-shop.com/9x20_lathe_spindle_collets_adapters.htm
I would turn the MT3 end first, that would allow you to seat it in the lathe spindle to drill and bore the hole for the end mill. Then as said above drill a couple of holes in the side of the holder for a grub screw and grind flat on the side of the end mill that aligns with them.

Dave

Hello Tanii51,
You can probably turn them down to suit your largest collet if you have a lathe with a carbide tool. I have two 1" P&N Unimills (3 flutes) Which I turned down to 3/4" and then threaded to suit my Clarkson Autolock Chuck. The threaded end is not as hard as the cutting end. Check it with the edge of a file.
Regards,
Russell

Originally Posted by Dave J

http://www.micro-machine-shop.com/9x20_lathe_spindle_collets_adapters.htm

ta dave....he makes me want to do things...just need to finish of the bathroom, paint the house....and then I might be allowed some time to myself to do all or some of those projects...lots of good stuff there for me