Motors & Stepped Pulleys

Visit your local motor shop or McMaster-Carr/Grainger. Also check the usual online suspects for used motors. Consider a 3-phase motor with a Variable Frequency Drive.

Brad.

Try W.W. Grainger http://www.grainger.com/
or Johnstone Supply http://stores.johnstonesupply.com

I just bought some pulleys from an ebay seller that had several viable options for my C&P…. I have yet to see how my pulley size ratio will work, but I am planning on using an 18.65” on the letterpress shaft and a 2” on my 1750rpm motor shaft. If my calculations are correct this should result in an impression rate of approximately 30 per minute since the letterpress shaft turns 6 times per impression. I plan on using a variable speed router control on the motor which I believe will reduce power/rpm by 80% which should cut me down to a maxed out speed of about 24 impressions per minute, for my novice use, I think that should be more than I need.

Anyway, the ebay seller is:

http://myworld.ebay.com/redsheller/?_trksid=p4340.l2559

If I have done the math right, you’ll get about 9.3:1 from the pulleys and 55+:1 by multiplying by the 6:1 gearing of the press, and dividing the result into the 1750rpm tells me you’ll get 31+ impressions per minute — pretty fast for feeding, at less than 2 seconds per sheet. Reducing that to 80% might be OK for an experienced feeder, but a bit risky if you aren’t good!

Bob

Yep, it will still be a bit fast, but the key is that the reduction in speed/power comes from a Variable Speed control, which means the TOP speed will be as you calculated and can be dialed down to near stop…..

Anyway, I’m glad to to have the numbers verified…. I am really curious to see how the router motor variable speed control will work….

http://www.amazon.com/MLCS-9400-Standard-Router-Control/dp/B001JHQ3G8/re...