Source of small gears?

[Roger Mills]

I recently acquired a Novitech shredder from our local Freecycle, in the knowledge that it wasn't working - and accepted the challenge of trying to mend it.

It had stripped the teeth on its (nylon) first stage reduction gear. Since the gear in question was fairly wide, I managed to make it work by moving it along the shaft a bit so that an undamaged bit engaged with the next gear in line.

However, after working for a little while, it promptly stripped the newly engaged teeth, and is back to not working.

Can anyone suggest a source of suitable gears to enable me to get it working again - preferably made of something a bit more durable than nylon. I cannot find a website or any after-sales support from the original manufacturer - so am looking for something which will fit rather than for the official spare part.

The gear in question is actually two conjoined gears. The input gear (which is undamaged) is a helical gear and is about 35mm in diameter and 8mm wide, and has 35 teeth at an angle of about 3 degrees. The output gear (which is stripped) is a straight spur and is about 12mm in diameter and 12mm wide and has (or rather *should* have!) 12 teeth. The shaft size is around 4mm.

I accept that I'm unlikely to find the exact thing, but two separate gears which could be joined togther would do - or I may even be able to re-use the input gear and just replace the smaller output gear.

TIA.

[SirBenjamin]

I have a large box of gears&springs of different sizes,these were collected over the years of servicing video recorders,CD drives,printers ect.

There's a website that does gears,however I'm not too sure on the name now but try GREENWELD Electronics? or type in google electroninc components.

[Steve Firth]

if that isn't correct have a search for "gear" on the Maplin website. They have several packs of different types of gears.

[Bob Minchin]

[Matt]

will send a (free) printed catalogue

[Clint Sharp]

In message , Matt writes

Which is full of useful information and formulae IIRC, worth it if you build things that use gears. They also do custom gears so if you can't find what you want you can empty your wallet and have it made!

[Andy Dingley]

So it didn't work with its original gears, when they were new and ideally aligned. Why should it be any better if bodged?

I'd ditch the whole geartrain and replace it entirely. It's not that hard to find worm-geared fractional HP motors (industrial scrapyards are my favourite). You can add one of these easily to the end of the shaft much more easily than you can sort out the innards of the old gearbox itself.

[Roger Mills]

Thanks for the information. Thanks, too, to the others who have suggested HPC or other similar companies.

Having looked at the prices on HPC's website - even of the 'budget' range - I get the feeling that it would be cheaper to buy a new shredder!

[The Natural Philosopher]

Indeed. Quality gears are not cheap..which is why cheap gears don't last.

[Roger Mills]

My logic was that, if I were to replace the nylon gear with a metal one, it wouldn't strip its teeth. Of course, it might then strip the next one in the gear train!

An interesting thought! I'd have to suss out how to control the motor though. The existing one has several wires going to it, and I fancy that it turns backwards and forwards - rather than continuously in one direction - in order to chop the strips of paper into short lengths.

[The Wanderer]

Having taken a quick look through some of the replies, there's one other source that might be open to you if you've a mind to pursue it! Quite legit if it works, email me if you're interested. The addie in the sig is live.