source for small cams and followers

One thing that comes to mind is to use the same gears, etc. that you are using, and make eccentrics to actuate the actions via pushrod or pull-pull cables in tubes.

Thinking like soldering a pin off axis on the face of a gear. (Does that make any sense?)

Gearing a couple sets of gears together like spirograph can get some pretty complicated motions going too.

Cheers Trevor Jones

Bend up a cam out of 1/8 rod and weld or braze it to the shaft; use a lightweight follower. As long as you actuate _really_ lightweight stuff with it and dress any welds on the working surface carefully it ought to stand up pretty well.

Oooooooooo! Me want pictures! :-)

Go to

and buy his DVD. You will see tons of ideas on how to arrange linkages, etc. Most are brazed from wire. Fascinating stuff, and incidentally, a great way to keep visiting nephews rivetted to the couch and out of trouble... --Glenn Lyford

Thanx to you and the other respondents. I didn't know there were cams in copiers and laser printers, so that is a good pointer. I don't have any pictures right now, but I will post some soon...

I would be happy

Dunno if it'll help ya but ask an appliance repair store for a couple of defective washing machine timers. If you can get enough covers off of one, you will find cams stacked as much as 6 high.

technomaNge

Emmo: I was just at a very large copier repair facility the other day looking for bearing and rod asssemblies. . They had several large copiers that were slated for the junk pile. Most of the parts are unfortunately, linear in nature. Actuators, slides...that kind of thing. I own several of these large copiers in my business. I have one in fact, that cost me over 40K 7 years ago, is out of service and is in storage because it costs more to move it or dispose of than it is worth. Weird.

Anyway, these types of machines, have motors, rack and pinions, air pumps, air tanks, cylinders, valves...all interesting stuff, but not a lot of cams and followers. Hope that info will save you some time.

-Mike

Steve: Why not take a short piece of round stock, drill a hole off-center, and braze a rod or shaft into it. I guess this is an eccentric rather than a cam, but the resulting action is the same.

This makes really good sense, and would be very easy to do - great suggestion !! A huge benefit is that I can easily make them any size that I might need - I have both 1/2" and 5" aluminum rounds that I picked up off the floor at Westbrook Metals. I also think that the followers or tappets would ride easier on rounds than on actual cams, especially if I were to use something like slot car wheels. My mental gears are turning...

Thanx!

Only problem with eccentrics is you have a much longer "activation phase" because the ramps are shallow. A cam gives a good "kick" to activate, then de-activates quickly. An eccentric slowly activates, then slowly de-activates (relative to the action of a cam)