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Pratt Whitney 13 x 30 model B (Motor pully & Clutch box pully Sizes)

miketig

Aluminum
Joined
Jun 30, 2022
Anyone out there know what size pulleys were on the Pratt Whitney 13 x 30 model B ???? it was recommended in the original specs to have a 3hp 1200 rpm motor but I cant find as of yet what size pulleys go to the motor or the clutch box on the rear of the machine. Any knowledge on this is highly welcomed !!!
Mike T
 
Anyone out there know what size pulleys were on the Pratt Whitney 13 x 30 model B ???? it was recommended in the original specs to have a 3hp 1200 rpm motor but I cant find as of yet what size pulleys go to the motor or the clutch box on the rear of the machine. Any knowledge on this is highly welcomed !!!
Mike T
See linked catalog
Drive pulley is 8"
Speed is 600
You would need a 4" motor pulley if on a 1200 motor, and you would need a smaller motor pulley (3") if motor was 1800

Probably be smart to not run it in excess of placarded top speed since it is a plain spindle bearing design from the early twenties
 
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Thanks, that is helpful and makes a lot of sense because it would match the shape of the guard for the machine . I am dealing with 4-3/4 " drive pulley that someone intended to be powered by a 6" motor pulley with a 1725 rpm motor that was never mounted to the machine. If I did the calculation correctly I came up with that some one was intending to run it at over 2216 rpm witch would be over double the 1200. The problem with the set up someone was intending on using on it is it is probably to fast, and the guard on the machine is only 6" at the bottom witch leaves no room for any clearance for the pully not to rub against it, I am also thinking that it would be better for the motor to have the smaller pully on it and the larger on the machine, unsure if it that matters but it seems it would. I am going to make a 8" drive pully for the machine and will make up a pully for the motor, if I am doing my calculations correctly I came up with 5.56" for 1200 rpm from a 1725rpm motor. If 1200 is the corect speed then all marking on the machine should be in sync with the specs. Thanks for the input, I will do a little more research to double check just in case, the link catalog shows an extra lever on the front of the machine than my machine has. My machine is 13 x 30 M-1395 serial # 230 it is not as exactly as shown in the catalog. Any more info is welcomed !
Thanks, Mike T
 
I just realized you said 600 rpm. I got 1200 on the brain for some reason. a pully @ 2.78" should put @ 600 with a 1725. Do you think there would be any benefit in using a 3600 rpm motor with a smaller drive pully ?
Mike T
 
Thanks, that is helpful and makes a lot of sense because it would match the shape of the guard for the machine . I am dealing with 4-3/4 " drive pulley that someone intended to be powered by a 6" motor pulley with a 1725 rpm motor that was never mounted to the machine. If I did the calculation correctly I came up with that some one was intending to run it at over 2216 rpm witch would be over double the 1200. The problem with the set up someone was intending on using on it is it is probably to fast, and the guard on the machine is only 6" at the bottom witch leaves no room for any clearance for the pully not to rub against it, I am also thinking that it would be better for the motor to have the smaller pully on it and the larger on the machine, unsure if it that matters but it seems it would. I am going to make a 8" drive pully for the machine and will make up a pully for the motor, if I am doing my calculations correctly I came up with 5.56" for 1200 rpm from a 1725rpm motor. If 1200 is the corect speed then all marking on the machine should be in sync with the specs. Thanks for the input, I will do a little more research to double check just in case, the link catalog shows an extra lever on the front of the machine than my machine has. My machine is 13 x 30 M-1395 serial # 230 it is not as exactly as shown in the catalog. Any more info is welcomed !
Thanks, Mike T
1200 is a motor speed. All that is really important as far as avoiding over speeding is that the upper pulley turn 600 as per the linked pub. Top spindle speed on the 13 is 525 also as per the linked pub
 








 
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