Not too long ago, I had to straighten a motor shaft - bent where the shaft left the motor - Shaft stuck out about 100mm[4"] and it it was out 0.5mm[.020"] at the end. I thought of doing flame straightening - tried it on some scrap material - it sort of works but easy to over shoot and hard to fine tune. Then I remembered an exceptional tool maker I knew back in the '70s - one day he was tweaking a shaft via peening - it stuck in my mind.
It was hard to find the info on that process - for a shaft you want to form a tool with a grove that fits the shaft - rounded polished edge. I set the bottom of the shaft on some copper - and peened - took a while. If I did it again I would use a press and get close - then peen the rest of the way. The key is I could dial in about .002mm[tenths] - much more accuracy than I needed, I was surprised what was possible. Once I finished I tapped the end for a while to see if it would move - applied a bit of heat - it stayed put.
I have a spindle that is just a tiny bit out - so in the back of my mind, I've wondered if I could set it up on rollers - indicate - map out where the ding is and peen it straight? Different metal than a motor shaft - but it might work? so I'm wondering if anyone here has wondered down this road? (There was an old thread here about straightening a spindle - mentioned flame straightening, press straightening - but nothing this delicate.)
It was hard to find the info on that process - for a shaft you want to form a tool with a grove that fits the shaft - rounded polished edge. I set the bottom of the shaft on some copper - and peened - took a while. If I did it again I would use a press and get close - then peen the rest of the way. The key is I could dial in about .002mm[tenths] - much more accuracy than I needed, I was surprised what was possible. Once I finished I tapped the end for a while to see if it would move - applied a bit of heat - it stayed put.
I have a spindle that is just a tiny bit out - so in the back of my mind, I've wondered if I could set it up on rollers - indicate - map out where the ding is and peen it straight? Different metal than a motor shaft - but it might work? so I'm wondering if anyone here has wondered down this road? (There was an old thread here about straightening a spindle - mentioned flame straightening, press straightening - but nothing this delicate.)