Cholchester Student gear cutting selector lever removal help

[Deema]

I’m really stuck! I had to take off the front of the gear cutting selector box to find out why the gears where difficult to select. I managed to do it without taking off the gear selector lever, but clearly to put it back on the lever needs to come off. After a few hours of fiddling, looking, thinking, fiddling again I've come to the conclusion either I’m missing a fastening or it’s truly stuck on. I’d really appreciate knowing how to take it off.

I found two grub screws that I’ve removed (nit shown in the manual), one in the centre and one that acted to maintain the index of the arm. I’ve tried to see if the indexing grub screw would also act as a jack to push off the lever, but either the lever is crudded or, the threads don’t go all the way through.

OK, I accept that this is a question I shouldn’t be asking, as I should be able to work this out myself if I’m ever to hold my head up as a metal chip maker! but I left my pride behind years ago and would welcome any help.

I found the cause of the gear change problem, the selector tumbler and gate had been abused and the tips of the gate were bashed. A quick file sorted them out. I was surprised that the metal used is very soft and not hardened. It was also a good opportunity to clean out area out. I’m not sure it had ever had an oil change! Luckily all the gears had all, their teeth. The gear box picture is before it was cleaned.

On a different note, I can’t see how the oil gets between the two galleries, there are two sump plugs for draining it, and the central pillar of the case has a gasket that runs up so nowhere for the oil to sneak around that I can see? The oil filler feed just one side.

 

[Boswell]

First, I have not direct experience with this lathe. I think that your second picture shows the situation well. The slot in the coller is there to allow the coller to be tightened around the shaft by the screw that goes through the coller below the shaft. To me that implies that once that screw is removed you should be able to press it off the shaft.

 

[Deema]

Thanks, that’s what I’d assumed. There was a cap screw tightening the slot which I also removed. I’ve tried gentle prying the gap part to release it to no avail. It’s got a bit of a death grip at the mo.

 

[kb58]

Probably time for a gear puller.

 

[Deema]

Yep, your right it’s looking like a gear puller......I just don’t want to try if there is a secret fastening I’m missing. The bit that has me worried is there was a grub screw in the centre of the shaft, can’t see what it’s for / what is was holding on. Again nothing in the exploded diagram in the manual to show one should exist! The end of the shaft looks as though it should have had a counter sunk screw rather than a grub screw, I’m just wondering if the end of the shaft is actually a cap and there is a nut under it.......but no apparent parting line or way of getting it off. I’ve tried screwing the central grub screw in to see it that jacks off the ‘potential’ cap.....but not torqued it too much as it’s a casting......and nothing happened.

 

[benmychree]

If you were able to remove the cover without removing the lever, why is it not possible to simply reverse the process and reinstall the cover?

 

[Deema]

There are three dogs on the cover that need to be aligned back into the shoes that actuate the gears. Getting everything to line back up whilst manipulating the cover back on isn’t I don’t think possible.

 

[hman]

Thanks, that’s what I’d assumed. There was a cap screw tightening the slot which I also removed. I’ve tried gentle prying the gap part to release it to no avail. It’s got a bit of a death grip at the mo.

If the threaded hole for the cap screw extends all the way through the casting, you can try slipping a narrow piece of steel into the slot and running a suitable screw in from the back end. Then carefully tighten the screw against the steel "barrier" to apply (and hold) opening pressure to the slot. This should make the application of a gear puller just a bit easier.

 

[Deema]

Thanks for the suggestion, unfortunately the threaded holes are both blind.

 

[Deema]

Thanks to everyone for the suggestions and input, it’s appreciated
I had another really good shufty around and couldn’t find any other fastenings so popped a puller in it and it came off easily. Phew!
I found that the centre of the lever is a cap and the set screw hole allows the pressed on cap to be removed. Under the cap is another fastening that I’m presuming attaches the shaft to the gear train. Anyway, the central set screw acts as bung to stop the gear box oil leaking out.
Oil changed and everything back together.