Flat belt step pulleys

Derf,
Those pullys are to good looking to actually USE! :D. Nice job. Have you crowned them as well or are my tired eyes decieving me? Any thought on Epoxy impregnation?
 
I have not made a pulley out of rolled steel, but I think it should be very doable... All of the flat belt pulleys I'm familiar with have a slight crown on them to keep the belt centered.

Good luck,
Ted
 
I fabbed up a 3 step flat belt pulley to match a driven pulley on a 7" Rhoades shaper. Materials were all repurposed and turned to size.
 
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That is a little radical putting a motor in direct drive to the pulley on the spindle. They generally on a retrofit to a motor drive, put a jack shaft in there to get the RPM's back down to the original spindle speeds, which probably topped out at around 400 RPM on the spindle.
Is that a No. 1-1/2 or 2 Brown & Sharpe mill?
 
I just went through the same unique situation with a Seneca Falls lathe. The solution I came up with works very well. The easiest way to fab up some cone pulleys is to build them from hard wood. I used some exotic south American wood of which I cant remember the name for the biggest pulleys and some purpleheart for the smallest. It is very hard and stable. I first started by building a sleeve to mount them to, and then turned them one at a time before I stacked and glued them all together.
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I have also made a pulley this way, but used softer wood. It may not work to make the steps the same sizes as the pulley on the machine; there is a method of designing step pulleys by graphic means (making a drawing) taking into account the center distance, drawing a radius off to the side halfway between the centers and projecting a line from the existing pulley steps to the center of the new pulley location; this method insures that the belt will have equal tension on all the steps and also allows the second pulley to be a larger or smaller size than the existing pulley. I found the method in an older Machinery's Handbook, 1960s, I think. An example of different size pulleys is the lineshaft drive Hendey lathes, the upper pulley had steps a good deal larger than the headstock pulley to raise the speed range.
 
I made these pulleys the same size as the ones on the headstock, and with a crown. They track just fine. The belt we were working with was an amateur version of a leather belt put on by the previous owner that was stitched in place. It was made from saddle leather and stretched quite a bit. We opted for a J12 poly vee belt, which was doable, but we had to remove the spindle and the back gear to get it on. No big deal, as we tore it apart to clean it up and paint it anyway. The poly vee belt has about 10 times the traction as leather and won't stretch, meaning it will probably last a lifetime.
When I get a little more time, I am going to start a thread about the whole resto-mod on this lathe.
 
The belt will wander if both pulleys are crowned, leave one flat.

Greg
I have never seen a pulley that is not crowned as you suggest, and I have seen and used a lot of them; they are all crowned to keep the belt centered on the pulley. If the belt wanders, it is likely the fault of the belt itself, it likely would have a stretched spot in it.
 
I have never seen a pulley that is not crowned as you suggest, and I have seen and used a lot of them; they are all crowned to keep the belt centered on the pulley. If the belt wanders, it is likely the fault of the belt itself, it likely would have a stretched spot in it.
May be wrong, thought it was in the Machinery's Handbook that I read it many years ago, but can't find it in the house copy. I've only done a couple of flat belt drives and a stroke sander that was about 7 feet between the pulleys. One flat pulley worked on them.

Greg
 
Rolling the pulleys will work fine, I've had some made fors awmills. CAST iron will transmit more power thans teel, woodw ill alsoA good shop should be able to roll thec rown in steel ones,,,cast or wood willha ve to be turned. jackshaft to the motor,a s they likely will be too long for shaft mount
 
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