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Show 1847: Potter's wheel question

Caller Jim said someone told him an old transmission could be used to make a home-brew potter’s wheel, and he wanted to know what sort of junkyard transmission to use. Ray suggested to find one that the gear shift lever attaches directly to the transmission, like for many pickup trucks. To avoid having to deal with the linkage presumably. The way it works apparently is an electric-motor drives the input shaft, and the wheel is attached to the output shaft. You get however many speeds the transmission has.

I got to thinking (rarely happens :wink: ) , for a direct drive to the potter’s wheel configuration like that, the transmission would have to be oriented up and down instead of horizontal. Right? So how would the gears inside the box be lubricated? Wouldn’t all the transmission fluid leak out? Or is the idea to just run the gears dry?

The transmission can be oriented in any direction as long as there is a differential to spin a shaft that is vertical.

The caller intended to attach the wheel directly to the output shaft. Ray said a welder would probably have to weld on a flange. There’s no differential. The wheel’s plane from what I understood is oriented 90 degrees to the output shaft.

Edit: I got to thinking I’d read about this issue before here. Maybe this was the thread.

It may be that the gears don’t need to be lubed in this application.

Bevel gear to leave the trans horizontal and turn the output up.

My guess you could just apply a little grease to the gears once in a while and get away with no other lube. That’s the way my cement mixer works.

Transmission would be under such a light load used as a potters wheel residual gear lube is probably adequate.
Having said that, by the time your done with a project like this you could have purchased a very good wheel.

Artists often have more time than money I guess. The $$ expense for the callers proposed project probably isn’t that much, but indeed there’s gonna be significant time investment between the idea phase and making pots. Ray told the caller he could walk out with a wheelbarrow full of used transmissions for $50. Now I think about it, I seem to recall that old vw (air cooled engine versions) junkyard transmissions were repurposed for potters wheels too.

True. But then there is the coat of the electric motor, building the supporting platform etc. when it comes to mixing water with electricity I would want a tool made for the job, not something cobbled together.
Just my humble opinion.

I don’t understand why you’d need a transmission at all. A wheel hub, a steel wheel, and a piece of MDF that you cut to match the diameter of the wheel is all you need to make the spinning part. You can either hook that to a motor or a kickplate depending on how utterly cheap you want to go.

You don’t want pottery work pieces spinning really fast, so it’s not like you need a 5-speed potter’s wheel. And using the wheel setup, you’d eliminate the possibility that your slip will find its way inside the transmission and end up binding it.

That said, if you can afford a kiln, you can afford an inexpensive potter’s wheel…

I don’t know what the optimum rpm a potter’s wheel is, but probably has to do with that and the available motor speeds available from inexpensive motors. For a given power, low rpm motors tend to be more expensive than high rpm. And with a transmission the artist would have 3 or more rpms to select from. The steel wheel & hub idea would work if the diameter was ok for the artist, but may develop a problem eventually w/the axial-directed bearing load. Still you make a good point, for a super-cheapo manually-rotated potters wheel, the hub and wheel might work out pretty good, especially if you got a hub style using the conical roller bearings.

Put the motor off to the side and hook it to the wheel with a belt. Put drill press pulleys on both to give you variable speed options.

Or do it the way a real potters wheel does it and have a motor and a variable speed controller so you can get exactly the RPM you need for whatever you’re throwing. The optimum RPM changes depending on what you’re doing, but it’s generally on a scale that stops in the mid-200’s.

But really, no matter what solution you come up with to use car parts to throw pots, you’ll end up with something of questionable utility because it’s doubtful you’ll get the surface and wobble down to the point where you have the precision you need to throw pots without wrecking them. Meanwhile, you can often get a good kickwheel on Craigslist for under $100. :wink:

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