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I have a tinnie Mutoscope and the bevel gear that drives the coin chute mechanism has broken a tooth. The bevel gear has 21 teeth and measures 1.43” (36.31mm) at the biggest diameter.

I have been unsuccessful in obtaining an off the shelf replacement. I could get it re-manufactured or possibly I could repair, but this maybe difficult as it is aluminium or MAZAC. Does anybody have a suitable replacement or know where I could get one?

Also, the crown wheel has seized (this machine has been in storage for many years). It appears to have expanded and is pressing against the cast iron frame. It is not possible to get a feeler gauge blade between the wheel and casting in some locations. To avoid putting the wheel under any stress, I propose to drill out the wheel boss to allow it to be removed. I will then turn up a new boss and shaft. Has anybody else had this experience? Please see the attached image.

On the repair shop program recently I think the chap repairing a mutascope used the bevelled gear from an old hand drill as a suitable replacement. Just a thought.

Alternatively, I once repaired a missing tooth from a bevelled gear by ……
* Thoroughly degreasing the area
* Putting a blob of Epoxy Putty in the gap where the missing tooth would have been.
* Gently turning it a few times so the crown wheel impresses the shape.
* When it goes off sand/cut/grind the excess off.


That was over 5 years ago, and it's still fine now.

BP

Thanks for your suggestions. I will dig out an old drill brace - could be lucky and find that the gears are a match. Failing that, I will try the epoxy putty trick. I have used this when repairing the castings on my clutching hand machine, but it was a non moving part. I will also loctite some small posts into the gear prior to applying the epoxy to act as reinforcement. Thanks again.

That smaller bevel gear is a later replacement as the originals were brass. You could also cut a slot (keyway) into the body where the tooth is missing and glue in a flat alloy piece.