yep - I sat mine int he garden on a camping stove. Once they get burning you can actually switch the stove off. Leave to annoy the neighbouts for 20mins, leave to cool and the whole lot crumbles out.
Tidy up with sandpaper/wire wool.
You can be far more environment/neighbour friendly if you drill out the main rubber with one of those round cutters (used to cut big round holes in wood etc.) I did this. If you get it right you can drill out the centre tube with lots of rubber attached and end up with only a thin layer of rubber stuck to the inside of the housing. You'll need to lubricate it as you go or it will seize the cutter.
Did both bushes in about 30-40mins total but there was plenty of time in there to have a beer whilst watching the inferno.
Apart from annoying the neighbours, does anybody know what grade of alloy and in what temper the casings are made? Attacking the alloy casings with a burning torch may well soften the casing considerably, if they were heat treated to start with.
They are pretty big numb lumps of metal though, so I don't suppose it is likely to cause any problems in normal use. It would make the steering pretty dodgy though, if the wings snapped off the butterfly
This process was a little less vicious than it looks! We pressed the majority of the rubber out in a fly press, then 'warmed gently' the remaining rubber to get it out.
Being an alloy the bushes conduct heat extremely well, but they do not hold it for long. It is unlikely that this moderate heating and cooling will change the properties of the casting or weaken it in any way.
P.S I'll let you know if the wheels ever drop off!
hmm - when I did it, as long as the rubber had been given a good burn, it just crumbled out once it cooled and I tidied up with a bit of wire wool. Try a curved file with an aggressive cut to get the last of it out?
I have tried a wire 'brush' attachment in a drill, by pure coincidence the one I had was exactly the same size as the ring of metal, but all it does is create fantastic amounts of friction. This just seems to occasionaly throw out something similar to the 'marbles' at side of a race track.
The rubber softens up which causes it to become VERY sticky, I have tried a vicious file etc. but these have exactly the same effect.
well, along with my suspension overhaul i have planned for this weekend (i have 4x Bilstein shocks, poly ARB bushes, new VGX front pads sitting on my floor and i have a left side wheel bearing, 4x ball joints, a tie rod end and 6x control arm bushings in the mail, due by friday at the latest).
i will be taking the front rotors, the left side steering member (for the wheel bearing) and the 6 control arm bushing brackets to a machine shop to have them pressed out... the thought of putting a torch to something as important as a control arm mount makes me nervous. of course, a moron in a machine shop using the wrong size press could easily do much more damage than any amount of damage that propane torching could do.