14-11-2011, 10:59 PM
So, to continue:-
Step 13 was to measure the shaft. It's 1/4" as Col said. However, I can't find any evidence of how the shaft is located. I can only think that it's the knob and the detent mechanism, at least in this version.
Step 14 was to photograph the 4 shaft positions - there's no real point Posting them.
Step 15 was to remove the Switch Blocks - I can't think of another name.
Step 16, finally, was to remove the shaft. Anyone of a nervous disposition should stop looking now. It was still very stiff to turn. The bearing surfaces are the front and back plates - there's a clearance hole in the middle one. A gentle tap on the end would move it but only a little. I was very nervous about applying any serious force because I didn't want to damage the partitions, which were only supported at the bottom at this stage. Anyway, I decided in the end that my best bet was to grasp the shaft with a big pair of pliers and tap the pliers. In a way this was 100% successful in that the shaft was extracted with no damage to the partitions. The bad news ius that the shaft is now in 6 pieces as it broke at its weakest points, as Col found. In retrospect I suppose the way to do it would be to make a gadget to push the shaft out of the end plate. Anyway, what's done is done. I don't think the replacement needs to be ultra accurate as there's clearly a lot of (potential) slop in the arrangement. However, Col, if you made a sketch of your shaft when you made the new one it would no disadvantage to have it.
So, I need some material to make a new one. Just like Col I favour Brass. Stainless Steel would be good but it's often a pig to machine. Anyway, Brass is more in keeping with the era.
Alan
Step 13 was to measure the shaft. It's 1/4" as Col said. However, I can't find any evidence of how the shaft is located. I can only think that it's the knob and the detent mechanism, at least in this version.
Step 14 was to photograph the 4 shaft positions - there's no real point Posting them.
Step 15 was to remove the Switch Blocks - I can't think of another name.
Step 16, finally, was to remove the shaft. Anyone of a nervous disposition should stop looking now. It was still very stiff to turn. The bearing surfaces are the front and back plates - there's a clearance hole in the middle one. A gentle tap on the end would move it but only a little. I was very nervous about applying any serious force because I didn't want to damage the partitions, which were only supported at the bottom at this stage. Anyway, I decided in the end that my best bet was to grasp the shaft with a big pair of pliers and tap the pliers. In a way this was 100% successful in that the shaft was extracted with no damage to the partitions. The bad news ius that the shaft is now in 6 pieces as it broke at its weakest points, as Col found. In retrospect I suppose the way to do it would be to make a gadget to push the shaft out of the end plate. Anyway, what's done is done. I don't think the replacement needs to be ultra accurate as there's clearly a lot of (potential) slop in the arrangement. However, Col, if you made a sketch of your shaft when you made the new one it would no disadvantage to have it.
So, I need some material to make a new one. Just like Col I favour Brass. Stainless Steel would be good but it's often a pig to machine. Anyway, Brass is more in keeping with the era.
Alan
