Repairing Metal Corrosion

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Repairing Metal Corrosion

Postby TRS80 on Sun Mar 06, 2011 10:29 am

I recently acquired an old DEC HX-590DP server which I would like to clean up and get running again. The insides are interesting.... looks like a small army of mice had been living inside. Even if I can't get the actual boards and PCB cleaned up and operational it is a nice looking case and would be worth replacing the PCB to be my DEC SIMH host.

What is a good appeach to cleaning up metal corrosion on the case? Mainly this is surface rust. Easy enough to sand the spots back and Terry... you mentioned contact cleaner in your SX-64 post.

Regards

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Re: Repairing Metal Corrosion

Postby tezza on Sun Mar 06, 2011 4:42 pm

Hi Andrew,

A DEC HX-590DP. Sounds like a beast of a machine! :)

I'm not sure on the best product to use here? Apart from those spots on the SX-64 I haven't done any "save from rust" restoration. Yes, I think it was contact cleaner I used then, and only because it had "protects from rust" on the can. I'm sure there are other products more fit for purpose.
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Re: Repairing Metal Corrosion

Postby TRS80 on Sun Mar 06, 2011 9:12 pm

Thanks Terry... I have another equally rusty power supply I can use as a test candidate first.... it is easy enough to clean off the surface rust, will try the contact cleaner but failing that the machinery grey spray paint I used when I rebuilt the tractor might work.
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Re: Repairing Metal Corrosion

Postby Carcenomy on Sun Mar 06, 2011 10:33 pm

You would need to neutralize the rust first - look into automotive rust repair products. Once it's started it's nearly impossible to stop, so unless you can neutralize it, you won't be able to stop it forever... :(
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Re: Repairing Metal Corrosion

Postby lizardb0y on Mon Mar 07, 2011 6:26 am

I learned the other day, from a preservationist working with marine archeologists, that rust can be converted back to iron using a caustic soda solution and a small electrical charge. It needs very precise control of the solution concentration, and takes a long time.
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Re: Repairing Metal Corrosion

Postby TRS80 on Mon Mar 07, 2011 2:49 pm

Thanks for the comments guys. I have the products already to neutralize and then touch up with spray paint. I did a similar exercise with my Iseki tractor. I thought there might be something special that had worked well for computer chassis but I guess it shows that metal is metal no matter where you find it.
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Re: Repairing Metal Corrosion

Postby Gibsaw on Tue Apr 26, 2011 11:17 pm

lizardb0y wrote:I learned the other day, from a preservationist working with marine archeologists, that rust can be converted back to iron using a caustic soda solution and a small electrical charge. It needs very precise control of the solution concentration, and takes a long time.


mm.. indeed, they did a stabilisation of the revolutionary war confederate submarine "hunley" by this method. (http://www.hunley.org)
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