The taillight housings I'm working with are arrow-straight but have quite a few pits in them. I'd like to reuse these if possible - because finding replacements may not be. Can the pits be ground and filled with lead, then rechromed? Or is there another process you recommend? Thanks.
Google search pot metal plating. There are several places that repair and rechrome. Most are in the classic boat restoration biz.
Yes, the piece was originally chromed. I would like to perform the repair myself if possible. To save money and to know that I did it..
It really can,t be done at home.How the pro's do it,they drill all the pits with a fine drill to remove the all of the corrosion then they heliarc the holes and grind smooth.It now gets copper plated and buffed until flawless,then nickel and chrome plated.It is expensive but if you can,t find the parts in good shape it your only option.Phil
I tried heliarcing pot metal to no avail. However I have filled holes in it with 90% silver silbraze and paste style flux. FEDER
The place I used to work at, Custom Plating Specialists in Brillion, WI, do some amazing stuff with really pitted pot metal. I'm sure they can be saved. A couple words of wisdom, though. You won't save a dime doing your own prep work. We sometimes charged extra for stuff that someone had already worked over, because it all had to be undone and redone. And a good plater isn't going to risk reputation putting plating over a piece that they didn't prep themselves. Depending on the piece, it's not always more expensive to redo a pitted piece, some stuff looks good with the old plating on and looks like shit when stripped, and vice versa. And I don't know that I've ever seen a chrome shop drill out a pit and weld it shut. That seems way too complicated, some pieces would be like swiss cheese when you're done doing that. We chemically stripped the pieces and blasted them to get the "dead metal" out of the pits. Then they were ground and bad pitting was filled with silver solder. Then heavy copper, sanding, more copper if necessary, buffing, and flash copper before it went to the nickel tank. In short, yes it can be saved, and you aren't saving money by prepping it yourself.
That's what I needed to hear. Since I've got your ear, how heavily pitted can a bumper be before it is unsalvagable? For instance - this DeSoto bumper. I know the passenger side bumper guard is shot because it has holes in it. But while the lower half of the bumper has no holes in it, the surface rust is heavy and I bet the sheet steel underneath is thin. I know it's impossible to say without a close inspection, but in your opinion do you think this is something that can be chromed? Thanks for the help guys!
Using the bumper and hood on my project, the 341 Hemi and side trim are going to be used to get a convertible on the road. Unfortunately it is just too far gone to use. Frame was completely rotten and every panel had thin steel, it would not have even been possible to weld patches to most bady panels. Shame - a factory red/white 2dr HT Firedome..
As much as possible will be salvaged from this car and like Danny said, this sucker is wasted... btw...When I am done on my 57 Convertible, I will offer up the remaining bits to the masses here and at the Forward Look sites pretty much just to make sure as much gets used as can be used...these Desoto bits are like hens teeth....if you need `em, you will have a rough time finding them.
As for the bumper, it's hard to say from a picture. When I sent my dad's '65 GTO bumpers off to get plated, they beat them with a pick hammer and punched a couple holes in the rear, then sent it back saying it was too thin. If you can tap it with a hammer and not do any damage it's probably fine. Northstar/keystone bumper in Minnesota does amazing work but they've been getting very picky with cores lately, be it bent or rusty. They're so booked up with work I think they just want the gravy stuff. You're best off to take the bumper off the car and bring it to wherever you're going to have it plated, have them look at it and tell you if it's useable or not.
Bumpers are easy, lots of metal to work with. As for potmetal, we have it stripped, and copper plated first, then solder it up (95-5 works well), vixen file sand, and let the plater do the rest...even if they have to put some heavy copper on it and resand it smoother.
Has any one actually had any experience with muggy weld working with pot meal? I'm always suspicious of any product you have to buy direct from a manufacturer or carnival/fair/trade show spruker that you can't buy through the shops.
Cecil N. Muggy's Super Alloy works great. I think it has been covered here on previous threads along with cheaper sources for the same or similar product - a search might bring it up. PM sent.
You can braze to pot metal. The trick is to remove all the active iron. I use an electrolysis process that I use for rust removal. First I wash the part in degreaser and then rinse. Then Battery charger gets connected to the part and to a sacrificial piece of iron or steel. Positive to the part, negative to the other conductor. One tablespoon washing soda per gallon of tap water. I let the part plate out the corrosion. It should only take a couple of hours at 2amps, but it will do no harm to run it over night. The idea is to have a line of sight from the negative conductor to the part you are stripping of rust. I have a 300 gallon tank with 20 bars that I change out and clean after each part, but you could easily do this with several pieces of sheet metal or rebar or anything iron or steel. Now... Presure clean the part to force off all the residue and your ugly part will be rust free and have only raw Iron and some black spots of a material called martinite (iron/carbon molecule that is quite hard). Take some borax and disolve it in hot water and paint the part with that solution. This will be your flux. Take the entire part and heat it to the temp you will be brazing to. Dull red or cherry read. Don't melt it or allow it to deform. I use an oxy acetalene torch and make slow passes until the entire part is hot enough, but not so hot that the flux burns off. Then, touch your brazing rod (also fluz covered) to the pits and fill them up. There will be some pits that will not fill and you will have to grind into that area and reclean and reheat and do teh same work. It is quite doable. If you can get to this point, why not powder coat the part? If you are building it for you, nobody cares. If you are buildinig a 1000 point restoration, you would not be on this board....
I have seen very pitted pot metal & bumpers at a shop in Oregon City. They metal spray it with copper, then sand off the hi spots & it fills all the pits.On the spendy side, but it works great.
Theres a lot of information on this thread, which means theres probably more than one 'right' way of repairing pot metals, but if you go to this website and watch the videos it looks like its exactly what your after - something you can do yourself on the cheap.
For some additional discussion of this, and a start-to-finish effort with prices, check out this earlier thread: http://www.jalopyjournal.com/forum/showthread.php?t=279714
Danny ... Squablow has it completely right ... don't try to do the prep yourself ... let the Pros do the entire job (you'll be $$$ ahead in the long run). When we were restoring our '57 Chrysler 300C, just about every pot metal piece was badly pitted ... we took them to a very reputable chrome shop in our area ... their work was sub par ... so we dropped them off at another (more expensive) plater in our area ... but his work was just as bad as the first shop (and he blamed the first plater for poor prep work) ... so my father finally "jumped off his wallet" and sent the pieces down to Master Plating in San Diego ... and all pieces came back spectacular! ... including the tail-light housings and the (extremely pitted) trunk emblem bezel: These pics don't do the plating justice (and no, those aren't dents, they're reflections). Oh and BTW, Master Plating is no more ... it was shut down in 2002 due to "environmental issues."
It's pot metal http://en.wikipedia.org/wiki/Pot_metal you guys with your take it to a pro, one wrecked mine stories. If you don't know someone's work or can't afford it and have a clue you can surface copper yourself, they can put it on thick so doesn't require solder
I spoke at length over the years with three different platers about this very subject. Here are the highlights: Yes, it's true most good platers don't want any prep work done preferring to avoid unwitting mistakes. One of them explained for example that grinding away the chromed/nickel, copper plating to get the base metal further contaminates it. They prefer to electrically strip all that off. It usually costs more for the plater to correct improper metal prep than to deal with a virgin piece. Pot metal pitting is corrosion. ALL of it must be taken out to avoid seeding of future pitting. Paul's Chrome at their booth told me once at a NSRA meet in Knoxville that once the pitting is removed they continue to build up copper plate with intermediate buffing and more copper plating until the pit is covered and level with the original surface. His display demonstration of Desoto grille teeth showed exactly what he was talking about. The stuff isn't cheap but it's one of those areas best left to a pro. If I were you I'd go to a show near you where a reputable chromer is present and discuss your job with him.
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