Quote Originally Posted by John S View Post
Build one.
Absolutely
There is one which I build. It takes MT3 ER20 collet chuck or anything with MT3. It's not final design, but gives idea how it will looks like. There will be MT3-like taper on the top to install set of reduction pulleys. I rather needs to go down with the speed than up so taper roller bearing will be perfect for this.
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So far hollow shaft including M30/1 thread for preload nu,t internal and external MT3 tapers is turned. I'll try to make some pic of it.