[gavztheouch]

I have a DIY laser cutter that uses two 15mm diameter 20mm pitch ballscrews to drive the y-axis.

My trouble is one of the screws is badly bent and because the machine is so lightly built the bent screw is moving the gantry and causing a wobble to appear.

I would like to try and bend the screw back into shape. Has anyone had any luck trying this themselves, if not where should I be looking to find a pro to do it for me and what should I be looking to pay. Bear in mind the screws themself cost me £80, cheap enough to attempt a staighten myself.

I have been practicing with some 10mm stainless steel rod. It is proving difficult to get it anywhere near staight. My setup is a pair of vee block and a dial test indicator and a relatively straight cast Iron table of my belt sander.

[dmalicky]

It's possible but not easy. I was able to improve one, but couldn't get it super straight. I rolled the shaft on a surface plate to try to find the bend point. Rolling half-on and half-off helps narrow the problem zone. The trick, of course, is to apply just enough force to bend it but not over bend. "Calibrated" dead-blow hammer strikes can work, or if you have a milling machine, use the z.

This is how the pros do it:
[ame="http://www.youtube.com/watch?v=Vg7KHaHd9I4"]Eitel RP-16 straightening press - ballscrew demo - YouTube[/ame]