Thank you John. That would be 0.2", as far as I know no such cutter/drill exists so it looks like I'll be manufacturing one from silver steel – it will probably be a flycutter.

Would a 5mm x 30 mm HTD belt do the job, the cutter for making those pulleys is 1/8"?

Edited By James Owens on 27/10/2013 18:18:14

Thank you for the replies. I have found out that a 5 mm HTD x 25 mm wide belt should be well within the the power rating, so my miller will be getting those and not the 8 mm HTD belts. My reasoning is that the pulleys are cheaper to buy and more available and, more likely, easier to manufacture – as they only require an 1/8" ball nosed cutter.

I will be using the 8 mm HTD pulleys I bought on another machine at a later date but will use most of Doug's suggestion by using a 5mm ball nosed cutter and doing 3 passes, one down the middle of the tooth and then off-set each side with another pass taking off 0.07mm. It will be interesting to see if it works, I'll draw it up in CAD first though so I get the depth right.

James

Edited By James Owens on 29/10/2013 14:48:03