Rust never sleeps
- Thread starter Redsward
- Start date
@JDW covered this topic in one of his SE Reloaded build videos..
I've done similar in other hobbies, and as an aside if you decide you want to do some zinc chromate plating I can hook you up!
Thanks ! not sure I will be plating anything just want to arrest the rust so it doesn't get any worse !@JDW covered this topic in one of his SE Reloaded build videos..
I've done similar in other hobbies, and as an aside if you decide you want to do some zinc chromate plating I can hook you up!
I used a Hammerite rust remover gel (available in the UK) to treat the drive cage and the interior chassis of my SE/30. I bought the Mac recently from a large lot of retro computers and parts from a house clearance place - I think a collector must have died
Although the case has been battery bombed, the motherboard was OK and already recapped so I presume it's a Franken-machine. It has 20MB of RAM and a GG Labs MACSIMM ROM but it was missing its case screws and SCSI cable, and its hard drive was dead. However, the auction photos had showed the sad Mac icon on screen so I knew its board was ok. I had to refurb the SuperDrive and clean the whole machine and keyboard as it was all filthy. The CRT has decent geometry and no burn-in of the menu bar. A 50 pin IDC ribbon cable and a BlueSCSI and it was back in business.
I wanted to treat this rust since it's directly above the motherboard and loose grains of rust could cause a short. I was able to treat the rusted chassis itself without stripping out the CRT and and analogue board thanks to the gel. My technique was to apply it for a few hours at a time then scrape at the loosened rust with a piece of wood while wiping off. This worked much faster then relying on the gel alone (which I had done for the drive cage). I was able to get this result after I think one evening and applications at regular intervals for the whole of the next day. Probably about 10 applications of the gel. Once all the rust was gone I wet sanded it to reduce the appearance of the pitting, and then finished it with some finer grain wet and dry paper, and finally a light wipe with some WD40. You can still see where the acid/corrosion has been, the light in that finished picture was particularly forgiving. But the corrosion is gone. Hopefully these pictures give you a feel for what is possible.
I have taken the precaution of replacing the PRAM battery with one of these:
www.tindie.com
May this Macintosh last another 36 years!
This Mac came with the maroon coloured Apple carry bag, which was another bonus - but it will need its own refurbishment. The foam in the lining has degraded and it sheds fine black powder everywhere so I can't use it. I have seen this described elsewhere so I think it's a common issue.
Although the case has been battery bombed, the motherboard was OK and already recapped so I presume it's a Franken-machine. It has 20MB of RAM and a GG Labs MACSIMM ROM but it was missing its case screws and SCSI cable, and its hard drive was dead. However, the auction photos had showed the sad Mac icon on screen so I knew its board was ok. I had to refurb the SuperDrive and clean the whole machine and keyboard as it was all filthy. The CRT has decent geometry and no burn-in of the menu bar. A 50 pin IDC ribbon cable and a BlueSCSI and it was back in business.
I wanted to treat this rust since it's directly above the motherboard and loose grains of rust could cause a short. I was able to treat the rusted chassis itself without stripping out the CRT and and analogue board thanks to the gel. My technique was to apply it for a few hours at a time then scrape at the loosened rust with a piece of wood while wiping off. This worked much faster then relying on the gel alone (which I had done for the drive cage). I was able to get this result after I think one evening and applications at regular intervals for the whole of the next day. Probably about 10 applications of the gel. Once all the rust was gone I wet sanded it to reduce the appearance of the pitting, and then finished it with some finer grain wet and dry paper, and finally a light wipe with some WD40. You can still see where the acid/corrosion has been, the light in that finished picture was particularly forgiving. But the corrosion is gone. Hopefully these pictures give you a feel for what is possible.
I have taken the precaution of replacing the PRAM battery with one of these:
MacBatt CR2032 PRAM Apple Macintosh battery by Siliconinsider on Tindie
MacBatt CR2032 PRAM Lithium battery replacement for Apple Macintosh computers
www.tindie.com
May this Macintosh last another 36 years!
This Mac came with the maroon coloured Apple carry bag, which was another bonus - but it will need its own refurbishment. The foam in the lining has degraded and it sheds fine black powder everywhere so I can't use it. I have seen this described elsewhere so I think it's a common issue.
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