Purchased a sewing machine motor off @#$%& it runs at 7000rpm it has a footswitch and a 5/8 pulley on the motor now whats the average rpm on a rod wrapping machine?and what size pulley do I need to step up to to get the rpms I need for power wrapping.



thanx steve

Steve,
The lower the maximum rpm the more resolution you will have or the finer control you will have with the foot pedal. I would not make the maximum rpm more than about 500 rpm. To get the size of pulley that you will need just divide the 7000rpm of the motor by the rpm that you want the wrapper to have and then multiply that number by the 5/8" of the pulley that is on the motor. In other words the ratio of the motor rpm and the wrapper rpm will be the inverse of the ratio of the two pulleys. At a wrapper rpm of 500 you will want a pulley that is 14 times larger than the 5/8" pulley on the motor or about 8 3/4", a wrapper rpm of 400 will require a pulley that is about 11" and for a wrapper rpm of 300 you will need a pulley that is about 14 1/2".

any ideas on where I can get a 14inch lightweight pulley?

If your motor has a foot control to allow for variable speed you can put a stop mechanism on it to keep it from turning 7000 rpm and you would not have to have as large a pulley. Kind of like putting a governor on a go cart motor. You could do that by drilling a hole in the base of the peddle (Being careful not to hit any wires) between the base and peddle. them mount a bolt to it with a nut on each side of the metal of the base to lock it in place. You want the bolt so that it is pointing up toward the peddle, so that then the peddle is pressed it is stopped by the bolt. Then thread the bolt up or down until you determine which is the best speed for you.

Steve,
Several of the vendors on the right that sell the Batson or Pac Bay wrappers will also have or can get parts. I think that the pulley on those wrappers is about 6" which would result in your wrapper having a max. speed of about 600 rpm. You could also probably get a chuck from them.
You could use some sort of mechanical limit on the foot pedal as Steve Gardner is suggesting. That would certainly be the simplist but you will not have much torque and very limited control, a very small amount of movement of the foot pedal will result in a large change in speed.

I bought a "Cabrillo" variable power control which I also found on @#$%& and pluged my sewing motor into it
and pluged the power control into the wall. The power control has a dial setting for power output just like a
pac-bay power wrapper and a foot pedal already wired in. There are switches for on, off, pedal control, and
manuel full power. A very cool unit!! I mounted a plastic chuck mounted directly to the motor shaft (no pully)
and still had OK control via the pedal. Would work better with a headstock and pully though.

I may place it on the Buy/Sell page as I do not need it any longer. Maybe the motor as well.

Raymond Adams
Eventually, all things merge, and a river runs through it..