soldering galvanized sheet metal
- Thread starter wazzabie
- Start date
if I recall from my plumbing & heating days in school, clean it with sulphuric acid and solder with ( used to be 50/50) solder with paste flux.
Rockable
Well-known member
Lead Free Acid Core Solder
Black Swan's Lead Free Acid Core Solder is a lead free wire solder that combines 95% tin and 5% antimony alloy. It is a general purpose solder for sheet metal, radiator repair and galvanized gutters. Acid flux is in the core of the solder.
Dagny
Well-known member
stay brite no. 8
619DioFan
Well-known member
Jbweld it.
The bucket is used to hold drinking water. Would this be a safe solder to use?Lead Free Acid Core Solder
Black Swan's Lead Free Acid Core Solder is a lead free wire solder that combines 95% tin and 5% antimony alloy. It is a general purpose solder for sheet metal, radiator repair and galvanized gutters. Acid flux is in the core of the solder.www.blackswanmfg.com
Pinemarten
Well-known member
JB Weld, some random epoxy, candle wax, chunk of tallow or lard.
jsaw
Well-known member
Everdur, silicon bronze. I was told that back in the day it was used to join galvanized roofing because it melted at a temperature that was low enough that it did not damage the galvanizing.
The silicon bronze rod’s lower melting point makes it ideal for joining together thin sheet metal, galvanized steel, and nuts and bolts, too. It’s nice for sheet metal work because the lower melting temps means less heat, which equals less warping when compared to TIG with, say, an ER70 rod. And you can still sand a…
See more on millerwelds.com
The silicon bronze rod’s lower melting point makes it ideal for joining together thin sheet metal, galvanized steel, and nuts and bolts, too. It’s nice for sheet metal work because the lower melting temps means less heat, which equals less warping when compared to TIG with, say, an ER70 rod. And you can still sand a…
See more on millerwelds.com
Rockable
Well-known member
You said "lead free". As far as I know, those buckets were originally soldered at the seams with lead based solder. This should be safer than that.
seber
Well-known member
All plumbing solder is lead free. Has been for at least 70 years. Clean it well and use acid core plumbing solder. Be sure to neutralize the area after.
dnschmidt
Well-known member
Have you ever considered buying a new bucket? Seriously the cost of the lead free solder, the flux and whatever else you need would seem to me to exceed the cost of a new bucket. You're going to have to grind off the galvanizing to get the solder to stick anyway so that's just going to promote more corrosion which obviously has already started. If I cared enough about it I'd TIG braze it but you need to remove the galvanizing to do that anyway.
rlitman
Well-known member
I'm nowhere near 70, and I distinctly remember lead solder in the hardware store plumbing section, because the EPA only banned it in 1986.
For the OP, soldering onto galvanizing can be difficult in the best of cases, but now that your bucket is already corroded, it will be hard to get anything to stick. I think your best bet would be to skip the solder and try the stuff made to propane torch "weld" aluminum. It's not a good welding product, but should work here, because it's mostly zinc and cleaning agents.
dutchgray
Well-known member
One of our plumbers is still using lead solder for non potable applications, as it is a bit easier to use.
Can still buy it here in the UK, but can't use it on drinking water systems.
no way . 20 maybe, I have half a 5 lb roll of 50/50 tin/ lead that gets used on occasion as it flows better & lower temps required
neophyte
Well-known member
You can still purchase 50/50 lead tin solder, because it’s still used for a bunch of applications not involving potable water or food.
If you want solder or brazing rod for potable applications, look for alloys that have an NSF rating.
Soldering, brazing, and welding rods are all available in NSF rated versions, although the alloys used sometimes make them a bit harder to use.
For corroded surfaces, you usually need to sand or brush all the corrosion off to get to bare clean metal.
There are repair sticks and powders that can be rubbed onto galvanized netal to repair the galvanized surface, but I’m not sure whether any of those are NSF rated. (I think they usually contain Cadmium).
If you want solder or brazing rod for potable applications, look for alloys that have an NSF rating.
Soldering, brazing, and welding rods are all available in NSF rated versions, although the alloys used sometimes make them a bit harder to use.
For corroded surfaces, you usually need to sand or brush all the corrosion off to get to bare clean metal.
There are repair sticks and powders that can be rubbed onto galvanized netal to repair the galvanized surface, but I’m not sure whether any of those are NSF rated. (I think they usually contain Cadmium).
seber
Well-known member
Of course you can buy tin lead. It just won't be advertised as plumbing solder.
kd3pc
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run small sheet metal screw in....one and done.
housewolf
Well-known member
Yes.
I haven’t done a bunch of soldering on galv sheetmetal but I have done some. Clean it up as best you can, smear some flux on it, and go to work. Keep your heat low by increasing the distance between your work and the torch. You may have better luck applying the heat on the outside of the pail while applying solder on the inside. We use what’s called a “chip brush” about 1” wide. You can use this to clean up your patch while the solder is still soft. Seems like a fair amount of work in lieu of replacing the pail with a SS one but I don’t know how large it is. I have one that holds about 1/2 gal I hang in my dogs kennel.
On 50/50 solder; it’s certainly been used on potable water within the last 70 years. I like to use it soldering a brass water closet flange to a lead stub since the lead melts so easily but that’s about it. Everything else I use lead free on.
danski0224
Well-known member
The galvanizing would be etched with muriatic acid, applied with a small flux brush. Wherever you spread it, the solder would stick. And if you get a good whiff of the vapors coming off of the metal, you'll seriously regret it.
Some put a little acid in a glass jar and add some small pieces of galvanized metal to cut/dilute the acid.
The heating/soldering would be done with a tinners iron. This is a chunk of copper (they come in different weights) on a metal rod with a handle that is heated over a flame. The copper is tinned and shaped accordingly. There are new fangled tinners irons with the flame built in.
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danski0224
Well-known member
It isn't easy. There is a skill to preparing the iron and more skill to apply the solder.
Flatwork is easy compared to pulling the solder up with the iron.
dnschmidt
Well-known member
Is this a serious question? How much does another bucket cost? The entire idea seems stupid to me.
Have you read half the posts on this forum before? Honestly fixing a hole in a bucket is better than some other stuff you see here.
My dad was a sheet metal man, and would routinely solder scuppers and roof jacks to make them water proof for roof use. Muriatic acid to eat away the zinc, then bar solder with a copper soldering iron and blowtorch for heating. Not potable water mind you. That was mid 70's.
rlitman
Well-known member
Don't forget to cut free any hair tangled on the bucket handle.