Where to buy gears

Am asking because I can find suppliers of expensive high-precision gears but this is for a piece of garden equipment so something relatively rough and ready would do.

Incidentally, I changed my mind from belt drive to gears partly for reasons of speed reduction. AIUI a single-pole induction motor would run at approximately 2800 RPM. If that's what I end up using then I will need to reduce that by between 20 and 30 times (yielding between 140 and

A while back I found HPC Gears of Chesterfield tel. 01246 268080 email snipped-for-privacy@hpcgears.com very helpful:

If not then try Arc Euro Trade Ltd in Leicester tel. 0116 269 5693 - the owner Ketan is very knowledgeable:

Alan

I don't think you want gears, I think you want a *gearbox* (or a geared motor) where the shafts and bearings, lubrication, and protection are also sorted out for you. And then a crank on the output shaft.

I'm of the same opinion. Open gears in a environment of grit and dust is asking for trouble. Pulleys and belt drive might be a better option.

Mike

I'm a great fan of belts but even so they don't take kindly to grit

Nor will the bearings

Yup, grab a sheet of plywood, and make em...

Just design them and print the template:

Stick it to the ply and cut out with a bandsaw, scrollsaw, jigsaw etc.

bike gears and chain?

I'd use pulleys and drive belt. Can slip if pushed - rather than shear.

I think what I would do is look for a small second-hand cement mixer with a knackered drum. Remove the motor and gearbox (which already come bolted together) and throw the rest away. Fix a crank to the drum spindle which will be going at about the right speed.

Or even one of these

They do the kinds of gear I need but at outrageous prices, e.g. a

All I wanted was a small drive gear turning a very large driven gear. Imagine the way a starter motor turns the flywheel of an engine.

I can't see a need for a gearbox but it looks as though I might have to use two pairs of gears to get the RPM reduction needed.

Pulleys might do. One trouble with them is tensioning the belt without putting too great a lateral force on the large driven pulley. I think it would be pulled off to one side unless it also had a very strong bearing.

By contrast, toothed gears don't have the same lateral pulling force.

Maybe. Would need two chains and the first would probably run at quite a pace. So it might be lethal!

This simple reduction drive is way harder to do (economically) than I expected. I assumed there would be a shop chain which sold gears and customers could just walk in and select the right parts. Machinemart sells various related things but not ranges of gears.

I need about 120 RPM. Much greater than a cement mixer, I would have thought. At that speed the cement wouldn't mix but would stick to the drum all the way round in a sort of wall-of-death feat. :-)

Interesting that just 375 watts can mix cement!

worm drive may work.

You need very little lateral force on a cambelt style gear system

375 watts is half a horsepower.

Take another look at using a mains electric drill in screw driving speed.

Mike