My lathe has a potentiometer to control its variable speed function. Obviously that is connected to a couple of obscure electronics boards of Chinese manufacture, not directly connected to the motor. The motor is an 850w DC one. In the process of being moved from one house, to storage, and to our shed, and then into the newly built workshop, the knob appears to have been bashed, shoved, or whatever, as the aluminium panel its mounted in was very slightly distorted, and the lathe will not work. it is a 4k7 linear pot, with the usual nut to mount it in the panel hole. I do not fully understand potentiometers, or which wire is which, but I managed to replace this one about 5 years ago after I'd mistaken the knob securing method and destroyed it when removing the knob to replace it with a bigger one. The replacement one has often been a bit "hesitant", so if this is indeed the reason my beloved lathe refuses to function, I'd like to get a mechanically and electronically tough one, of decent quality. I can solder stuff in place (NOT tiny stuff!) as long as I know which wire is which, this is the level of my electronics knowledge, i.e. not much...
OK, so what sort of pot should I buy, and where to get it. RS seems a bit overkill for one weedy component, and I tend to avoid ebay, but Maplins is effectively dead, so what and where? This potentiometer will get twiddled a lot, like up to 50 times a day, for a couple of days a week, perhaps. I have a feeling wirewound is best, but that may be a well out of date opinion. There aren't really any space constraints, its quite a roomy housing.
My only efforts at testing it with a multimeter (in situ) showed that resistances did indeed vary as I twiddled it. Its quite possible that a crap Chinese electronics board has indeed failed, but I'd at least like to get it controlled by a decent pot. My exploration of the forward/off/reverse switch (which is the last thing before the motor) puzzled me, as I was expecting to see a variable DC voltage on its output terminals, but a mains tester screwdriver lit up, and my multimeter set to a 200v DC range resolutely showed 0v.
Help!