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Gallery, Projects and General => How do I?? => Topic started by: Chuck in E. TN on October 04, 2013, 08:50:07 AM

Title: Motor Speed reduction gearbox
Post by: Chuck in E. TN on October 04, 2013, 08:50:07 AM
 I’m looking for a speed reduction gearbox to reduce the rpm of a ¼ hp AC 1725 rpm motor to about 40 rpm. I have searched online and prices are amazing.
The application is a sand muller for my foundry.  Anyone know a good source for said gearbox? Anyone have plans that a novice could follow to build one?
 [font=]Chuck[/font]
Title: Re: Motor Speed reduction gearbox
Post by: 75Plus on October 04, 2013, 09:03:39 AM
Chuck, you may be able to adapt a treadmill incline motor for this application. If so they can be bought for a song and you can sing it.

Joe
Title: Re: Motor Speed reduction gearbox
Post by: Chuck in E. TN on October 04, 2013, 09:13:33 AM
Joe, that's my fall back plan. I have a 1 1/2 hp treadmill motor and a MC-60 controller I could use. If I do use that one, I'll develop a method of quick removal so I can move it to other machines.
I have collected about 6 treadmills but only 2 had the MC-60 controller. The other MC-60 is running my X2 mill at the moment.
Chuck
Title: Re: Motor Speed reduction gearbox
Post by: unc1esteve on October 04, 2013, 11:49:07 AM
Can you cut a worm gear?
Title: Re: Motor Speed reduction gearbox
Post by: Chuck in E. TN on October 04, 2013, 12:13:08 PM
I  don't have any indexing set up yet, unless I could do it on a rotary table. I think Ive seen a large tap used as a worm cutter.
The worm is just a large screw thread, right?
Chuck
 
Title: Re: Motor Speed reduction gearbox
Post by: RussellT on October 04, 2013, 12:28:58 PM
Hi Chuck

You could screw cut a worm on the lathe, the coarser the thread the better, an acme style thread is what you need.  If you do it in steel and make it much longer than you need you can then use part of it to hob a matching gear in aluminium.  Cut a couple of slots in the thread you've cut to make it resemble a tap and put it back in the lathe.  Mount your gear blank on the cross slide so it's free to rotate and advance it to your rotating tap.  You'll need to make the gear blank about the right size for 43 teeth.  A steel "tap" should manage a single gear wheel in aluminium without hardening - if you make the tap long there'll be some extra cutting edges.

Russell
Title: Re: Motor Speed reduction gearbox
Post by: unc1esteve on October 04, 2013, 04:51:24 PM
Good book with instructions for cutting worm.
http://www.bookdepository.com/Gears-Gear-Cutting-Ivan-R-Law/9780852429112
Title: Re: Motor Speed reduction gearbox
Post by: 75Plus on October 04, 2013, 06:12:01 PM
Chuck, the incline motors are 120 Volt AC and run at a constant speed. They are actually a power driven nut which runs the screw up and down. In your application the screw would become the output shaft.

For speed controls, the KB Electronics KIBC 125 is an excellent control for treadmill motors and can be found at reasonable prices on the Ebay. With a heat sink they will handle up to 16 amps which is close to 2 HP.

Joe