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Harold and Susan Vordos Harold and Susan Vordos is offline
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Default Rusted gears usable? (Harold)


"Ignoramus13560" wrote in message
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On 2008-01-16, Harold and Susan Vordos wrote:

"Ignoramus25819" wrote in message
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On 2008-01-16, Harold and Susan Vordos wrote:

Best of all, it doesn't attack parent metal. That's one of the negative
attributes of HCl.


Harold, how serious of an issue, practically, is hydrogen
embrittlement related to HCl? For example, let's say that I dunk a
lifting chain in HCl for 20 minutes. Would it become unsafe
afterwards? I always appreciate your knowledge and opinions.

i


I can render only an opinion. For what it's worth: Yes, it would be a
problem. Hardened steel has an affinity for hydrogen, thus it is
readily
absorbed. What would concern me with a chain is the relatively thin
sections, which would likely be fully penetrated in short order. The
roasting process is simple----and would assure that there was no problem.
375 degrees F for a couple hours and there's no worry.


I did this to one chain a while ago, and do not mind taking corrective
action if necessary. Is that correct to say that taking it to an oven
as you described, can be done quite some time after it was derusted?

Thanks Harold. Maybe your advice would prevent me from getting in
trouble.

i


I'm not privy to any information that dictates that the operation can't be
performed at a later date. I would assume doing it late is better than not
doing it as all. As long as the chain appears to be good now, you have
nothing to lose by following the procedure. The temperature is below that
which would alter the heat treat condition, so you have nothing to fear.

Harold