Author Topic: Crowning a pulley for a flat belt Question  (Read 367 times)

Offline Jim

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Crowning a pulley for a flat belt Question
« on: March 03, 2021, 11:02:23 PM »
Crowning a pulley for a flat belt, been trying on some ali before moving onto brass using the top slide set at 1 + and then set at 1 - and it ain't an easy exercise to achieve a simple crowned pulley! 

Any hints on how to do this? I thought this was going to be really simple, its kicking my arse!
Kind regards,

Jim

Offline steamer

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Re: Crowning a pulley for a flat belt Question
« Reply #1 on: March 04, 2021, 12:50:40 PM »
1 degree isn't much....5 might be better for belt tracking....try it out on the ali part first

A dead sharp tool with a small polished radius and a steady feed...consider a simple crank on the compound that you can spin smoothly

Got some pictures?    Lets see what it's doing?

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Mcgyver

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Re: Crowning a pulley for a flat belt Question
« Reply #2 on: March 06, 2021, 12:02:24 PM »
I've only seen them with a curve not two flats so thats how I've made them.  You could create the radius the way I do radii; work out a table of X/Z movements and cut the steps with the compound and cross feed.  I think on the one below I just eyeballed a few steps and hit it with a file, its not super critical stuff.  Then finish with a file and emery to round out the corners of the steps.