I'm thinking of making myself a slot mortiser using a router as the power unit. One problem I haven't resolved. Routers run in the 25000 rpm range while dedicated slotters hang in around 3600 rpm. Is there a way to slow down a router without sacrificing HP?
Also, found one plan for making the device on the WWW. You guys have any sites to recommend that could expand my knowledge base?
I don't believe you can reduce speed w/o proportionally reducing HP in a single phase electric motor. You might consider reducing speed mechanically by means of pulley system, but that would necessitate modifying the router a bit...and would also take up considerably more room.
I thought there were a few electrical engineers on this site at one time, but maybe that's changed...or I'm wrong. They could tell you why this can't be achieved. I believe there is a formula associated with this:
HP = torque X speed / 5250, so when you reduce the number for speed (rpm) then the quotient becomes less as well (quotient being the HP)
Dumb question: What is a slotter? At first, I was thinking that you were talking about a horizontal router/mortiser like David Marks uses, but then I realized that reducing speed wouldn't really be necessary...or would it? I'm relatively new to woodworking. -Bobby
I, too, think it's a risk. You could dado the shelves in, but only glue them on the back (or front, or maybe middle) 1/4 or so of the joint. That would leave the balance of the wood free to move. If...