Timing Belts

[JoeHarris]

Edit: My machine doesn't use this system it use's short belt from motor to screw then long belt between screws. This is because my screws are 1300mm centres so suits it better.

Images of Jazz's set up - link below (posted when I was asking a similar question!)

http://www.mycncuk.com/forums/showth...xis-CNC-router

[Jonathan]

using 24T on screws 48T on motor but you can use any size pulleys that suits.

Within reason - using too small pulleys can stress the belt too much or risk leaving not enough belt teeth engaged with the pulley. I avoid using less than 15T pulleys for this reason.i

[JAZZCNC]

Within reason - using too small pulleys can stress the belt too much or risk leaving not enough belt teeth engaged with the pulley. I avoid using less than 15T pulleys for this reason.i

If you look I said any belt that "suits" and obviously too small giving wrong tooth engagement wouldn't suit would it.?

Am I missing something but, isn't it possible to locate the motor between the two lead screws and fit two pulleys to the motor to drive two belts?

Yes it is and that's how I did it first time but found it hard to get even tension on each belt.! It also means having the screws offset or one machined longer or like in my case where I hadn't allowed for this when machined due to originally going to use slaved motors screw extensions needed making.

The way I have it now isn't pretty but it works very very good and super reliable and easy to swap ratios.!

[Jonathan]

If you look I said any belt that "suits" and obviously too small giving wrong tooth engagement wouldn't suit would it.?

True, hence I clarified for anyone who does not know that a small pulley not be suitable.

[Ricardoco]

I will PM you about those as i cant use them on this project, but i can on another that im having some bits made for on pay day Ive just got to send the drawings off..

Rick