Is there a metalurgist in the house?

[compo]

Every now and then we do daft things. I did yesterday.

I removed my chain and cassette to thoroughly clean them in a tub of paraffin with a stiff paint brush. Afterwards I warmed the cassette on the gas, without getting it too hot, and that dried it nicely. Then I had to work out how to remove the paraffin from the chain, and from inside the rollers. I coiled the chain and sat in on the gas, just for a few seconds to burn off the residue. It worked OK, but a couple of links must have got too hot and have blued. No worries on the chain, I just fitted a new one rather than risk failure. Then I suddenly thought about the cassette. I assume they are heat treated during manufacture, so will my heating of it be likely to adversely affect it. It hasn't discoloured like the chain. I am just slightly concerned that the teeth may bend up when I put pressure on the pedals.

Guess what? I wont do that again!

 

[smokeysmoo]

I'm not a metalurgist TBH, but if I can STEEL myself a few minutes later I'll try and help.

I just need to IRON out a few things with this COPPER at my door



don't worry, I've already got my coat and left

 

[Drago]

That's a golden question. Did you alloy it to cool slowly, or we're uranium to quench it? Id be well brassed off me self.

 

[green1]

It'll be ok, heating it up for a couple of seconds isn't going to make any difference. Next time though just wrap it kitchen roll put it in a bag and spin it round your head a few times. Paraffin leaves carbon residue when burnt.

 

[compo]

I'm not a metalurgist TBH, but if I can STEEL myself a few minutes later I'll try and help.

I just need to IRON out a few things with this COPPER at my door



don't worry, I've already got my coat and left

Well, you're a GAS

 

[black'n'yellow]

next week: how to remove stubborn mud stains using a flame thrower...

 

[Globalti]

You will only make metal brittle if you heat it then quench it quickly.

 

[Tim Hall]

Not all metals surely. Memories of 3rd form metalwork classes, back when the world was black and white, we heated copper and quenched it to anneal it after it got work hardened. Still got the copper ashtray somewhere.

 

[compo]

Not all metals surely. Memories of 3rd form metalwork classes, back when the world was black and white, we heated copper and quenched it to anneal it after it got work hardened. Still got the copper ashtray somewhere.

We used to do that if we reused copper head gaskets on MZ motorbikes. I probably melted more than I managed to re-use so was always worth having a sheet of copper handy to cut out new ones.

 

[Red Light]

Well all I can say is you blue it. But no, it won't affect it unless you ran it under the cold tap while it was still hot.

 

[GrumpyGregry]

Even then doesn't it need to be heated to cherry red or some such for any material change (ba-dish!) to take place?

 

[numbnuts]

you would not have taken it up to cherry red 800-850c I bet the max termp would have been no more than 400 or lower so know you would not have damaged your chain
How do I know, I'm a Blacksmith

 

[Red Light]

I've blued the discs on my mountain bike once or twice doing long technical descents. They still work fine and they also often get quenched by splashing through a puddle or stream after a big descent.

 

[compo]

you would not have taken it up to cherry red 800-850c I bet the max termp would have been no more than 400 or lower so know you would not have damaged your chain
How do I know, I'm a Blacksmith

Thanks. I will accept that as a definitive answer taking into account your trade!

 

[bicyclos]

We used to do that if we reused copper head gaskets on MZ motorbikes

Were you in the MZ riders club by any chance? Your comment has brought back memories from the golden 80s.