Getting gears off these motors I bought

Hey everyone,

I bought a set of four NEMA 17 motors off eBay and they each came with a gear on the shaft (which is not the right pitch at all). I need to get them off to continue construction, but don't know how! They don't have set screws, so I'm not really sure how else they might be attached. I have tried gripping the gear in a vice and using a punch on what looks to be the shaft coming through the gear. I have tried prying up against the bottom of the gear, levering on the edge of the motor casing as well.

How else could this thing be attached. I guess threaded with a threadlock compound is possible. I posted some pictures on my build log on the wiki. Thav's build log

Thanks!

They're probably attached by using heat, as in heating up the gear so that it expands and then pushing it on the shaft where it contracts. You should be able to use a vise and punch like you were saying, Just give it a bit of force, you aren't going to hurt anything that way. Prying against the motor casing is likely to damage the shaft inside the motor or pull it out completely.

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Thanks for the advice, it game me the courage I needed to slam on them a little more. Instead of trying to grip the gear with the vice, I got some support under the gear and punched down the shaft. Worked like a charm. Updated my build log with pictures.

I used a propane torch to heat mine up a little and they came right off, no slamming or prying

Thav:

What's the url for your build log. I'd like to see it. Those eBay motors sure are cheap. Maytbe the way to go on my next printer.

Thanks

Roy

You can make a cheap mini gear puller using scrap metal, a tap and a screw.
Instructables has a pretty good description of how to do it at [www.instructables.com]