onelittleshop
Plastic
- Joined
- Apr 19, 2022
I've got a tiny shop and I often build prototypes. Periodically I've wanted a metal shaper. In my potential usage the fact it isn't cutting in one part of the action does not bother me at all. I desire cheap tooling I can grind to shape at 2AM, a predictable action, and a good finish. I've seen people use the carraige on a lathe with a HSS steel tool to shape a gear tooth in brass. I've done some research and found a document done of instrumenting a HSS steel cutter on a big metal shaper in India that broke the cutting ground edge off around 38lbs of force.
I don't need a very large shaper. I don't really want to beat an antique to the end or move a 400lb machine either. A small manual shaper like the smallest Perfecto metal shaper or Rapid Lime metal shaper would even satisfy my needs. After looking for a long time I've had little luck finding these small machines here.
So this has led to a question: given the high gear ratio of a lead screw, what stops someone from operating the ram of a metal shaper with a lead screw instead of a Scotch Yoke? I know they made hydraulic metal shapers, the lead screw would just rid the system of the hydraulics. I mean a lead screw may not be as fast reciprocating as a Scotch Yoke but surely a lead screw on dove tails can apply more than 50lbs of force pushing a piece of HSS steel as a tool. Sure you might not get to common SFPM rates if you go slower, but I guess that's not going to ruin the tool as long as it can keep cutting and the clapper works.
I'm thinking if someone just used some CNC steppers and appropriate parts there seems no good reason one can't achieve the table advance in sync with the ram either.
Am I missing something? With the average shaper in my area hitting $1,200 and a pile of stepper CNC stuff laying around this alternative seems economically attractive to me.
I don't need a very large shaper. I don't really want to beat an antique to the end or move a 400lb machine either. A small manual shaper like the smallest Perfecto metal shaper or Rapid Lime metal shaper would even satisfy my needs. After looking for a long time I've had little luck finding these small machines here.
So this has led to a question: given the high gear ratio of a lead screw, what stops someone from operating the ram of a metal shaper with a lead screw instead of a Scotch Yoke? I know they made hydraulic metal shapers, the lead screw would just rid the system of the hydraulics. I mean a lead screw may not be as fast reciprocating as a Scotch Yoke but surely a lead screw on dove tails can apply more than 50lbs of force pushing a piece of HSS steel as a tool. Sure you might not get to common SFPM rates if you go slower, but I guess that's not going to ruin the tool as long as it can keep cutting and the clapper works.
I'm thinking if someone just used some CNC steppers and appropriate parts there seems no good reason one can't achieve the table advance in sync with the ram either.
Am I missing something? With the average shaper in my area hitting $1,200 and a pile of stepper CNC stuff laying around this alternative seems economically attractive to me.