Has Anyone "made" A Foot Brake?

lowlife

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Just wondering? It seems if I could make the VFD stop the lathe quick enough that maybe I could hook a rigged up foot brake to a micro switch or something. Seems similar to an E brake knob.

Its getting late for me, maybe this is one of those thoughts that should remain in my head?
 
I've been planning on doing exactly that, I fitted my lathe's VFD with brake resistors (from China... 80 Ohms, 1500w as per manufacturer's specifications but about 1/10th the price), I'm planning a checquer plate bar hinged from the lathe base with a couple of springs, actuating a pair of normally-closed microswitches wired in series. Painted in yellow and black diagonal stripes so it's Obvious!
I already have a Big Red Button E-Stop over by the door so my nearest and dearest don't have to step over my corpse and dodge dismembered flailing limbs to turn the lathe off...
 
Thanks, that's the problem with an attached garage/workshop, they get annoyed by the noisy noise in the night, damn youngsters - in my day we wouldn't have heard it over the stereo :(
 
Ah a Foot Brake & a Neutral for mine would be sweet! Gonna require a few 20A interrupting current relays just to begin for me. I like the All Stop mentioned above. I have Emergency Kills on both sections of my lathe / mill combo. I just so happen to have them split onto separate circuits so the lathe can power feed milling operations. I know to kill the feed first if I get in a bind while milling, but was startled the other night when my wife came out (& forgot protocol). Oh & kill the mill too. The lathe portion is belt driven through a gear train - so there is 'coast' when stopping & no 'neutral'. I can see adding a simple hydraulic disc brake operated by a foot pedal - as the OP said - once the power is tripped. Back to lowlife's setup, If the VFD uses a stepper motor, would not a micro switch as he suggested halt the motor immediately. Assuming it has enough oomph to overcome all the moving parts it kept in motion?
 
Hydraulic disc brake would work - and you could add a second master cylinder teed into the hydraulic line, activated by a spring and with a solenoid to latch it "off" when power's applied that releases when power drops on hitting the Estop? You'd have to reset it each time you powered the machine up, but worth it maybe?
I've not thought about stepper motors, but the VFD with braking resistor does a pretty good job of stopping "on a dime" (as I believe they say in the rebel colonies).

Dave H. (the other one)
 
I already have a Big Red Button E-Stop over by the door so my nearest and dearest don't have to step over my corpse and dodge dismembered flailing limbs to turn the lathe off...

That is actually a good idea I need to file away for my future workshop build. If your wiring a new workshop anyway an E-stop at the entrance that kills all the sockets is a great idea (probably want to leave the lights on a different circuit).
 
My late 70's vintage Harrison M300 lathe has a foot brake that interrupts the electric latched circuit and has a friction brake that uses the v-belt grooves on one of the drive pulleys. It is a standard feature on many makes of engine lathes.
 
A foot brake is not something I have, but I have thought about it. My thoughts are to repurpose an electric 12V clutch from a car A/C unit, wiring it in, such that when the brake pedal, or the emergency stop button, is pressed The holding power relay for the motor drops out and automatically switches on the repurposed clutch/brake. The 12V supply comes from a battery which is always charged as I run 12V lights and coolant pump, and other bits around the shop. The clutch/brake would mount on the main spindle shaft, or alternatively on the shaft input to the headstock gearbox. Not sure yet, it's not an urgent project just a thought.
 
I was extremely uncomfortable with the time it takes for the lathe to coast to a stop after pushing the big red mushroom switch on the front panel. So I cobbled some things on the lathe to 'stop' the lathe more quickly.
Basically a trip wire or lever operated friction brake on the unused grooves of the motor pulley. It is a contraption that only a mother could love but it works and I feel better with it being available. I suspect that it stops the lathe more quickly than would my shirt wrapping around the chuck.

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