Restoring a corroded & rusty Fender chassis

Discussion in 'Shock Brother's DIY Amps' started by trancedental, Nov 3, 2012.

  1. trancedental

    trancedental Tele-Meister

    Posts:
    236
    Joined:
    Aug 15, 2010
    Location:
    London
    I've picked up a battered old empty '73 Super Reverb chassis with some corrosion & bit of rust & need to clean it up so I can use it for a Vibroverb build.:D

    I'm just wondering what's best to use for the task, I've scratched away some of the surface rust with wirewool & polished that area with metal cleaner & polisher & it looks much better. I assume that I need to seal where the rust as been to stop it coming back?

    Most of the inside of the chassis has corrosion, what's the best way of getting rid of that? Any recommended cleaning products? Has anyone managed to restore one of these old chassis?

    Cheers
     
  2. macaroonie

    macaroonie Friend of Leo's

    Posts:
    2,288
    Joined:
    Mar 24, 2009
    Location:
    Loch Lomond Scotland
    I'm a little rusty ( ha) on this but it would probably not cost all that much to have it re plated. Muric acid will get the rust loosened and all the dirt and as far as I recall the platers can go straight to nickel from there.
     
  3. trancedental

    trancedental Tele-Meister

    Posts:
    236
    Joined:
    Aug 15, 2010
    Location:
    London
    Cleaned the corrosion up with some white vinegar & metal shining pad / wet & dry. Got rid of the surface rust & used Brasso metal polish finish, it's a lot better now!

    I'm assuming that this chassis is made of stainless steel or aluminium? Parts of it now look almost like new, other areas will perhaps need more vinegar (or even baking soda :rolleyes:) to get the chassis looking really good!

    Took an hour so far :rolleyes:
     
  4. Viejo

    Viejo Tele-Afflicted

    Posts:
    1,047
    Joined:
    Feb 12, 2011
    Location:
    Central IL
    It is most likely zinc plated steel and will quickly develop that chalky gray finish again. I hate to rain on your parade but that chalky dull look is normal for a Siverface Fender chassis
     
  5. trancedental

    trancedental Tele-Meister

    Posts:
    236
    Joined:
    Aug 15, 2010
    Location:
    London
    I've got a Dual Showman Reverb chassis which has a slight dull shine to it which is the same as the chassis I've just been cleaning. Like this one.

    [​IMG]

    The cleaned chassis had lots of round spotted stains which were hard to get rid off, if it was a just flat dull grey look I would have left it alone.

    Might have been some type of corrosion or even some old mould which caused it?
     
  6. Viejo

    Viejo Tele-Afflicted

    Posts:
    1,047
    Joined:
    Feb 12, 2011
    Location:
    Central IL
    Yeah, I guess I worded my response poorly. I mainly meant to tell you that a chalky appearance would not be a problem. The only places I have had problems with corrosion on Fender chassis are between the chassis and the brass grounding plate and on the RCA jacks for the switches and reverb jacks
     
  7. trancedental

    trancedental Tele-Meister

    Posts:
    236
    Joined:
    Aug 15, 2010
    Location:
    London
    Thanks for the advice! :D
     
  8. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    New member, log time reader. I have recently acquired a 1963 Fender Showman (chassis only) that a friend of mine found IN THE TRASH!

    It's in pretty rough shape but all original, complete with the old fender "blue sausage" tone caps. The faceplates front and back are in great condition but the chassis has a layer of surface rust on every square inch inside and out.

    I am starting this restoration project soon and before I try some of the suggestions mentioned here, I thought I would run it by you guys one more time to see if some new tips have come up since this post in 2012.
     

    Attached Files:

  9. schmee

    schmee Poster Extraordinaire

    Posts:
    7,825
    Joined:
    Jun 2, 2003
    Location:
    northwest
    Wow, worst I've seen. Not sure there's a lot to salvage there. Face and Back plates. Possibly transformers will still work and tube covers. The turret board is too warped to use.
    I suppose you could acid etch the empty chassis and paint it somehow if your new grounding scheme can be done without using the chassis itself. But I wouldnt. Those amps dont go for a ton in good shape.
    I wonder if you might find a chassis somewhere. Also wonder if the BF bandmaster chassis is the same...? Many of those BM chassis had 4 power tube holes with two of them covered.
     
  10. schmee

    schmee Poster Extraordinaire

    Posts:
    7,825
    Joined:
    Jun 2, 2003
    Location:
    northwest
    What's the width of that chassis?
     
  11. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    I think you're right about the Bandmaster chassis. The Showman is 8 x 24 x 9½.

    What's your opinion on this. Another friend of mine offered to sandblast the chassis for me. It's surface rust.

    All the blue caps tested okay. I still have to bench test the transformers. I'm concerned about the obvious fire that took place on the rectification board and the possibility that the power transformer is toast.
     
  12. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    Oh, sorry. Those specs are for the head not the chassis. I'll have to measure it.
     
  13. FenderLover

    FenderLover Friend of Leo's

    Posts:
    4,976
    Joined:
    Jun 11, 2009
    Location:
    Minnesota
    We see a lot of relic guitars. A friend has a beat up 5E3 that he affectionately calls 'The Turd'. It looks the part, but really sings. I've always thought it would be fun to have a chassis that looked like that in a matching cab that worked PERFECTLY. Rebuild the electronics, leave the grime, and play it. It would get some looks for sure.
     
  14. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    Yeah, I had considered that because I don't mind the look. I just thought that the ground would not work well. I probably at least have to do something about the inside of it.
     
  15. FenderLover

    FenderLover Friend of Leo's

    Posts:
    4,976
    Joined:
    Jun 11, 2009
    Location:
    Minnesota
    Not really (regarding the ground). All sorts of electronics for decades are designed in plastic cases. An amp can be built in a plastic or wood case. The chassis need not be an electrical connection for circuit grounds, it should serve only as a metal shield and conduct fault current for the safety ground. Rusty or not, doesn't matter. Fender did use the chassis as an electrical connection for circuit grounds but didn't need to. It can be an exceptionally quiet amp if wired by modern practices over the old wiring layouts. It's a very hard thing for people to accept though, "It's gotta be wired vintage..."
     
  16. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    Good point. So I just need to put in a ground bus and that should do. As you can see, I'll have to replace the fiberboards.

    I don't plan on selling the amp ever so function over value is my main goal.

    Thanks for the idea.
     
  17. Bill Moore

    Bill Moore Tele-Afflicted

    Posts:
    1,126
    Joined:
    Feb 2, 2012
    Location:
    Silver City, New Mexico
    Faceman, I think if that were mine, I would pull everything down to an empty chassis, and glass bead it. You are going to have some pitting whatever you do to clean it, and this way all the rust is gone! (You could also plug any openings in the transformers, and blast the rust off of them too, maybe a coat of paint afterward).
     
    Wally and boredguy6060 like this.
  18. strat a various

    strat a various Friend of Leo's

    Posts:
    3,273
    Joined:
    May 9, 2008
    Location:
    Texas
    If the chassis is steel (it probably is) you can treat it like an auto body. Wash the hell out of it with a stiff brush and soapy water after removing as much rust as possible with a Dremel or a wire brush on a drill. Dry with a hair dyer. Get some "Rust Mortician" from the auto parts store. That will stop the corrosion from coming back. The parts you treat will turn black. It will never pass for original condition, but it will stop all corrosion in the original sites. You can paint it gunmetal gray if you like, or a metallic silver or gray. If you don't care how it looks, you can use a clear coat. Sand through the finish wherever you need to solder later.
     
  19. schmee

    schmee Poster Extraordinaire

    Posts:
    7,825
    Joined:
    Jun 2, 2003
    Location:
    northwest
    I think that is WAY beyond surface rust. It's surprising how transformers can survive being wet. They may work, hard to say. Beware that the Fender Amp Field Guide has some of these widths wrong. Why I asked it's actual width. Pretty sure the BM and Showman were the same but not 100%.
     
  20. Faceman

    Faceman TDPRI Member

    Posts:
    96
    Joined:
    Aug 15, 2018
    Location:
    Ohio
    Thanks for all the input guys. I'm going to tear it down next week, bench test the transformers and try to see more of what I'm dealing with with the chassis. With any luck, I can get it cleaned up and looking fairly presentable before I start the rewire process. I'll keep you posted. Thanks again.
     
    Wally likes this.
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.