OK, I want to add some reduction to my DIY router. I have 360oz servos and THK 5mm pitch ballscrews. (300ipm rapids are scary!!)
I'm thinking in the 3:1 range, and am checking out the McMaster catalog....

I'm leaning toward 3/8"width, .2" pitch .... will this be adequate?
How much backlash can I expect ? (near zero now)
Will they need to be accurately tensioned ?
Do I need a tensioner device (spring-loaded idler) ?
Will they stretch ?
How often will they need replacement ?

Any input/ opinions would be much appreciated. Thanks

Check this site, they have design criteria and formula's etc
http://www.sdp-si.com/
Al.