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By Wheaters
#9022
This is a non-Royal Enfield question, so I hope no-one finds that a major issue.

I'm hoping to find a recommendation for a UK company who can make a pair of small gears for a project of mine. The gears run in an oil bath. This is to make good a job that wasn't done too well by a company near me. The existing gears have always been very noisy and have now failed in service.

The gears I need are spur gears of approximately 42mm diameter, 15 mm thick with 41 teeth. Centre bore on one is 12 mm, the other 16 is mm. Accuracy is paramount. I can provide a pattern.

Thanks, any pointers gratefully received.
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By Wheaters
#80818
Papasmurf,

The gears fit inside the nose of an Eaton supercharger I've fitted to the Suzuki G10 engine in my Liege trials car. The supercharger was originally for a VW Polo TFSI. These superchargers unusually have an internal gear train stepping up the internal rotor speed to 1.93:1 because in the VW they are only "online" up to 3,000 engine rpm until the turbo kicks in.

I had a new pair of gears made to convert it to a 1:1 ratio for my purposes so it can run up to the engine rpm limit, which cost me more than the supercharger did. They weren't as well made as I had hoped (7,500 miles and they're K nackered and one of them has spun on the drive shaft), so I'm looking for an alternative company who can do the job at a sensible price.

As you say, gear cutting on this sort of small scale is a dying art. I've found online details of a few who can offer the service, but a recommendation from someone is always worthwhile.
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By Wheaters
#80841
I'm now sorted with a pair of gears after visiting HPC Gears, a company in Chesterfield. Their catalogue is very impressive!

My supercharger has an unusual internal drive setup which uses "in between" shaft centres and gear sizes, but HPC's tech expert recommended I fit a 42 tooth gear wheel mated to a 40 tooth one, rather using than two identical gears.

They had both in stock so with a bit of machining on the lathe, all now should line up and mesh perfectly. The gear ratio will no longer be exactly 1:1 as it was before (1:1.8 before I reduced it) but that isn't a problem because I can lower the boost slightly, to the car's benefit (its present 14 psi is a bit excessive for safety on a 9.5 CR).
By JonHill
#81179
Ward Engineering, Seaton Delaval in Tyne and Wear made a new sleeve gear for my 1925 BSA. Pricey but it's a complex full day's work for a skilled operator.
By Andy C
#81187
Dont know where you are in the world, but these people are absolutely brilliant & trustworthy.

Anything I cannot do I get them to do it.

Worth an ask:

https://hamlinsengineering.co.uk/

Good luck
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By Wheaters
#81189
Jon, Andy. Thanks for the info but I've already got sorted, as per my post of 7th Jan.

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