AboutDave Expertise machine tool setup and operation,selection and use of cutting tools, welding and metalfabrication methods, machining of plastics and metals,cad/cam,cnc,workholding and all related questions regarding metalworking and finishing
Experience over 25 years experience as a class a machinist in both job shop and r&d
environments.
Expert: Dave Date: 12/6/2005 Subject: Pulley Speed Calculation
Question Dave,
In you expertise paragraph, you do not mention anything about this question. However, I am positive that you might know about the subject. I am a metal sculptor and I want to build a tumbler to do some finishing on my pieces. It is going to be a Plastic barrel on top of 2 axels with two wheels on each one, but only one axel is going to be driven by a pulley system; the other is going to spin freely. I have done a lot of homework on the pulley system and I came with a formula that will turn the barrel at approximately 40 RPM. I just need somebody with more expertise than me to verify if what I did is correct. Here is the deal.
1)1HP electrical motor with a speed of 1725 RPM. This motor will have a 2” pulley (A) on the shaft.
2)Pulley (A) will drive a 4.5” diameter pulley (B).
3)Pulley “B” will have a 1” shaft (Axel)
4)The axel will have two 4” wheels mounted on it
5)These two wheels will drive the 20” diameter barrel
Will this system be able to spin the barrel at approx. 40 RPM?
Thank you so much for any help that you can give me.
Alfredo Alamo
Answer I didn't try to figure it out but I think you are close.
I may have a simple solution for you. If you use a DC motor you can use a speed control to vary the speed and dial in the exact speed you are trying to get. Modern DC motors and controls are reasonably priced and widely available. www.mcmastercarr.com should have everything you need. There are also many surplus web sites that deal in used DC equipment.
