proxxon KT70 CNC ?

That's a shame. It's going to be a deal breaker for me. I thought I would be able to just control the spindle speed with one stepper motor and sync it with the movement of the rotary tool rather than having to carve it out of a block. I think I'll just leave this project to one side for now and hope something changes.

It will do it but not just a case of one simple spiral cut along the length of your workpiece. Hopefully one of those suggesting using a CNC Router will chip in and say whats involved better than I can. Anyone?

This is a good example of how one of those small gantry routers will go about cutting a spiral.

https://www.youtube.com/watch?v=nzbcRKQO1U0

this is what I'm after. I realise it'll take more than one pass but I never really expected anything else. Obviously this is a bigger budget machine but it illustrates the principle of what i want to achieve.

https://www.youtube.com/watch?v=nzbcRKQO1U0

Edited By john constable on 27/06/2018 21:09:46

ha! Finally got it!

John, that is a legacy mill that I mentioned in the very first reply (though CNC not manual) to your first post about this we have gone full circle and not got very far.

The Stepcraft one achieves exactly the same result just has to take many more passes due to the low power spindle and small dia tool it has to use. The one in your video starts off with a large dia barly twist cutter.

Other good thing about a gantry router is that it can be used to cut the pockets and close fitting contrasting woods for inlay work on your boxes, carve textures and features and could even cut things like wooded hinges.