Kenwood Chef A701A fault...

[flyingsparks]

So today I have taken mrs sparks mixer apart after a burning smell was coming from it.
After removing the motor, it appears fine, and the burning smell is from a small copper contact on the underside of the plastic piece which moves up and down to vary the speed. Disassembled this and clean the contacts, it's better but still on low speed it is arcing a bit and smelling hot. Then on low speed the 450ohm wire round resistor started to smoke!
Two things, where can I get spare parts for this age of mixer, someone must do them because there are people who advertise refurbishing and repairs!? The other is how does the speed control work? I can't for the life of me see how when the knob is turned, the black plastic lifts up and down, which Varys the speed? Any ideas?
Cheers!

 

[DIYTom]

From your description it sounds like turning the knob switches the circuit into different value resistors, that then varies the voltage to the motor. Resistors are easy to find, Maplin, RS, Rapid, they should all do them. Just make sure it's the right resistance and wattage.
As to how the knob and slidey bit connect pictures or a drawing would help. Is there a hole on the knob and a pin on the slider (or vice versa) to join them?

 

[Nozzle]

this has a great thread on how it works http://howtomendit.com/answers.php?id=45632 Sorry for the cross posting (also ignore the notes about a triac as your mixer doesn't have this). It's a mechanical regulator, similar in some ways to an old skool centrifugal regulator you'd see on a traction engine or stationary steam engine. The minimum speed should be adjusted such that it is high enough so it does not stall when first started. I believe the regulator works by varying directly the magnetic set-up of the motor, rather than the AC supply to it. Very clever really!

Nozzle

 

[ban-all-sheds]

Any ideas?

Buy her a new one for Christmas. On balance, 2 + vs 1 -

1) Problem fixing this one goes away.

2) Problem finding something to buy her for Christmas goes away.

3) You might be going away on Boxing Day if she's not impressed by the idea of kitchen appliances as presents.