Summary for pot metal before welding Discussion
Pot metal before welding is the core issue here, and the thread suggests caution rather than a simple cleaning recipe. Stavros Pardini asked how to clean a 40 Ford grille before welding two bars back on, assuming the chrome should be ground off and asking what to use to remove impurities. Paul Bowsher replied that he was not aware of any method to actually weld pot metal. The editor’s note added that there is more than one supplier of rod and flux, implying specialized low-temperature repair products may exist, but not conventional welding. In a later question, another reader asked about chemically removing corrosion from a complex pot-metal object before painting, since scraping every surface was impractical. No direct chemical solution is given in the excerpt, so the practical takeaway is that pot metal is difficult to weld and may require alternative repair or specialized low-temperature methods rather than ordinary cleaning and welding.
Q. I have a grille to a 40 Ford that I need to weld 2 bars back on. I take it I should grind the chrome off of the areas I need to weld, but what should I use to clean it of its impurities. I have a cleaner from Dupont which is called a first klean – 3900, but I don’t think that would be right. please let me know thank you
Stavros Pardini
auto body – Redwood City, California, USA
2005
A. I’m not aware of any method to actually weld pot metal.
Jeffrey Holmes, CEF
Spartanburg, South Carolina
A. I believe that pot metal can be soldered and sometimes carefully brazed but not welded. Welding would mean using a rod of pot metal.
Gene Packman
process supplier – Great Neck, New York
A. It is said that “POT METAL” can be welded [look up def. in dictionary, mentions nothing about a “rod”] There is supposed to be a rod on the market that melts at 350 degrees, half of the melting point of pot metal, AND the most important, “FLUX” that allows the weld to be accomplished. But the company that sells the rod is slow to deliver and has a less than stellar appreciation of the customer. Too bad.
Paul Bowsher
– St Clair Shores, Michigan, USA
November 6, 2008
Ed. note: Thanks Paul. We’re sure there is more than one supplier of the rod and flux.
 | Hi, Paul. Whether to call it welding, brazing, or soldering may be more semantics rather than fact, but I agree with Gene. When a joining process requires flux for activation, and involves joining the parent metal with a different metal than the parent metal, and the melting point of the joining metal is half that of the parent metal, I too call it soldering rather than welding. I think people believe that welding is stronger than soldering — so someone selling a process would probably rather it be called welding :-) Regards,
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I would agree with you on the verbiage….HOWEVER, I now have a very nice upper grill bar for the 1950 Buick that had a BIG crack
> 50% its width. After taking the chrome off and getting past the copper, I applied the flux and welded, brazed, soldered and somehow joined and filled the crack. Waited about two days and sanded the weld, braze, soldered crack and it looks and FEELS like new. I am pleased, I now have a $300.00 part for 40$. I will have it re-chromed and bolt it on. I am looking forward to doing other pot metal projects with this muggy weld product, even though I do not like the company. Paul
Paul Bowsher [returning]
Rocking-b – St Clair Shores, Michigan, USA
December 12, 2008
Q. I’m cleaning a VERY extensive, complex pot-metal object for painting, and I want to get all the corrosion out before putting the paint on. To me, this calls for a chemical treatment, since I can’t quite access every square millimeter to scrape it.
Is there a chemical I can use to dissolve/wash away corrosion from pot metal?
N. Joseph Potts
– Miami Beach, Florida, USA
Q. My name is Jerrald Cline, I live in Modesto Calif.
The part I’m trying to join is a 1940’s Buick eight grill. Not sure how to attempt this job. Help please!
Jerrald Cline
Car restorer – Modesto,Calif. USA
August 4, 2010