How much crown should the small fan pulley have?

Post by **Rich Eagle** » Fri Jul 07, 2023 5:56 pm

I think we discussed this, and someone knew but I can't find it. My best one has .040 difference between center and edges.
If anyone knows or can find those posts, I would appreciate hearing.
Thanks in advance,
Rich

Kevin Pharis · Post by **Kevin Pharis** » Fri Jul 07, 2023 6:40 pm

I was able to dig up a flat belt pulley design formula to determine the amount of crown a little while ago. It showed that a 1-3/16” wide pulley was to have .018” of crown (radius dimension)

Post by **John kuehn** » Fri Jul 07, 2023 6:42 pm

There are several posts about fan hubs and pics of new ones and originals. But I couldn’t find an official Ford drawing and the specs. I have a few good originals and they still have a crown at least .020. or more. There is a member hand drawing but there isn’t specs on it.

Ford is bound to have a drawing in their archives I would think. Maybe someone has a picture of it on the forum somewhere?

Scott_Conger · Post by **Scott_Conger** » Fri Jul 07, 2023 7:38 pm

how does approximately 1% of the face width of the pulley (crown height, not diameter) grab you?

Post by **Rich Eagle** » Fri Jul 07, 2023 9:22 pm

All of that helps.
Thanks
I did find a drawing of the fan blade on the "Henry Ford" site but no pulleys.
Rich

kevinf · Post by **kevinf** » Sat Jul 08, 2023 9:56 am

Rich, I think Kevin has the right formula. I looked it up a while back but cant' seem to find it now. Funny story, a friend called, he was a machinist at a company that made fabric blinds. They ran fabric 60" wide and couldn't get the fabric to track. They called in one of their engineers and he put together a system of optical scanners and a controller to adjust the rolls to keep the fabric tracking. The system was so complex that it kept adjusting the rolls back and forth faster and faster, until it would finally shut down the machine and subsequently the production line. He called me and I said have you tried crowning the rolls? Apparently no one had ever heard of such a thine. I found the calculation, and he got approval to machine one of the rolls, and the fabric tracked perfectly after that. He was pretty happy until his boss told him to go through the plant and fix all the machines.
All the best and good luck with the fan hub,
Kevin

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How much crown should the small fan pulley have?

How much crown should the small fan pulley have?

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Re: How much crown should the small fan pulley have?

Re: How much crown should the small fan pulley have?

Re: How much crown should the small fan pulley have?