# 100 mk3 Back gear Missing a Tooth



## Vandal Machining (Mar 5, 2013)

Like it says the back gear is missing one tooth.  Is it possible to braze in a new one or would I be better off welding and filing?


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## RLWP (Mar 5, 2013)

The usual way is to cut out a slot, fix in a piece of metal and then form the tooth profile on that:







I posted those into another thread on broken teeth that I can't find just now. Those inserts are Loctited in place

Richard


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## Vandal Machining (Mar 5, 2013)

Do you file them to shape or is there a place to buy semi shaped teeth.  Also which loctite did you use.

If I'm seeing this right it looks like you did a straight through slot with an end mill and then glued in a square piece with a shaped tooth of that you shaped the tooth.

Thanks !


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## RLWP (Mar 5, 2013)

Close. I made the slot with a thin side and face cutter, because that's how the machine was set up at the time, fitted a plain piece of metal with the first bottle of 'strong' Loctite that came to hand. I then shaped the blank by turning the faces and tips in the lathe, and cut the tooth form with an involute cutter because I happened to have one

End milling the slot will work, and so will filing the tooth form if you have no other way of doing it. If you squash a bit of lead sheet against the side of a few good teeth, you will have a profile gauge to use when filing up



Richard


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## iron man (Mar 5, 2013)

The method shown here looks like it would work pretty good I never tried it that way but most of the one's I had come into the shop had more than one so I had to fill in with brass or weld them up and hand file them. But if you only have one tooth this might be the way to go.. Ray


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## Vandal Machining (Mar 8, 2013)

I am looking into getting a new back gear cut.  Is there any interest in a second one?


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## Vandal Machining (Jun 4, 2013)

Well, I couldn't get a quote to cut a back gear so now I'm back to fixing the one I have.  I've got the gear notched and need to fix in a piece of metal for the tooth.  After that though, is there a shop that someone would recommend to send the gear to that can cut the new tooth?

Thanks!


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