SA-200 Range switch replacement

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SA-200 Range switch replacementThis is an old work horse of an SA-200 that I'm freshening up. When finished, it will be skid mounted and sent out to stay on a job site as a stand alone mini welding shop. This is the same machine that received the recent alternator conversion.This post is mostly about removing a stuck control handle without damaging the switch. Although this machine needed a range switch, the same stuck handle problem could be encountered when replacing only the face plate or control handle.Attachment 23873The range selector switch needed to be replaced because the terminal board was burned.I had a nice clean donor switch still in the front panel of a cannibalized SA=200, but to remove the donor switch from the panel, the control handle would have to be removed first.The handles, -as with many exposed controls- can be very difficult to remove because of rust.So... I heated the tin cap red hot with a torch, this allowed the set-screw to easily be removed. I didn't want to stress the switch while struggling to pull the handle, so while hot I broke the switch handle away from it's hub. With the handle broken away, the very rusty and stuck  hub was accessible: Attachment 23874Hard to tell, but the control handle was red hot in the picture.Next I would heat the hub cherry red. But first I placed some heat shields around the switch shaft to protect the face plate.Attachment 23875The hub was then easily removed from the shaft. Top left is the replacement switch. Nice clean switch, it just had the handle stuck to the shaft. Marker points to the burned board on the old switch.Next I cleaned up the hub, and then plug welded the handle back to the hub:Attachment 23876The hub and shaft were treated to anti-seize compound.I know a new handle would have been a lot less hassle, but I didn't want to send the machine out without a handle, and then end up with the replacement switch's stem chewed up by vise-grips. Now with it's new range switch and charging system the old SA-200 is ready for service.Last edited by denrep; 10-19-2010 at 11:35 PM.