Dewhurst reversing switch

The Dewhurst reversing switch seems to be ubiquitous in lathes of a certain age, and mine is no exception. Here is a picture of it on the lathe :

I don't think that handle is original as there is a grub screw to lock it to the shaft. The shaft has a threaded hole through it, which I presume was to screw the original handle into - and look at the rather nasty welding!

When I got the lathe home, I noticed that it didn't always start when you moved the switch to the "Forward" position. I suspected a dodgy connection to the start winding of the fitted single phase induction motor. I wasn't wrong - when I took the cover off, this is what I found :

The rollers were badly pitted and corroded - and all the contacts were swimming in Copaslip Time for a dismantle and clean. But before that, notice that there is no earth lead to the earthing tag - I think a rewire of the machine is a high priority. At the moment it is being run from an RCD socket - as I suspected the wiring might be dodgy. Dismantling the switch simply confirmed this.

Here are the parts from the tumbler after dismantling and cleaning.

Re-assembled it worked a little better, but I think the contact bars need replacing. A piece of 1/4 inch stainless steel should do the trick. The short bars are 0.564 inches long (14.34mm) and the long ones are 1.25 inches long (31.8mm). When I get some stainless rod I will make new parts and fit them when I rewire the machine.