Garage Gazette

General Category => GENERAL DISCUSSION TO INCLUDE OFF TOPIC => Topic started by: jabberwoki on October 04, 2019, 09:23:19 PM

Title: Gearing question
Post by: jabberwoki on October 04, 2019, 09:23:19 PM
Of late my brain just cannot focus on simple problems like this, the thoughts just muddle up and disappear.

So on Chomper the motor drive pulley is now broken  , being cast iron I`m not gunna fuss with welding it so I`m getting another used one.
The question is to lower the start up load do I get a larger drive pulley or a smaller one?
I`m trying to relieve some of the start up load on my converter and I`m not worried about it running slower.
Title: Re: Gearing question
Post by: muddy on October 04, 2019, 09:34:23 PM
What the hell is a Chomper?

Anyway.. small gear means the motor will spin up to full speed faster
Title: Re: Gearing question
Post by: slip knot on October 05, 2019, 10:27:16 AM
Why not run the chomper on a dedicated VFD. They've gotten pretty reasonable for smaller motors.?
Title: Re: Gearing question
Post by: gtermini on October 05, 2019, 12:05:55 PM
I'll echo Slip. Using soft start mode on a VFD will be the easiest way to go. You may be able to run a VFD 3ph to 3ph with input from your generated power off your rotary.

The next easiest option will be some sort of slipper belt arrangement so you fire up the motor with no load, then clutch the machine into gear using an idler to tighten the belt. Put a big, old, badarse looking amp meter on the line and watch it as you pull it up to speed to keep things under control.
Title: Re: Gearing question
Post by: fatfillup on October 05, 2019, 07:59:31 PM
A smaller pulley  On the motor  will end up driving the Chomper slower and  I would imagine lessen the start upload.
Title: Re: Gearing question
Post by: pep on October 05, 2019, 08:16:08 PM
X 2 , could also in crease the bite as if it ain't good enough as it was.

LOL
Pep

A smaller pulley  On the motor  will end up driving the Chomper slower and  I would imagine lessen the start upload.