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bonderized sheet metal
what exactly is bonderized sheet metal
I really am not familiar with this but I think it is galvanized steel with some sort of inexpensive primer paint finish on it.
for heaven's sake get the information before you start posting replies as an'expert'! Bonderized sheet metal is a galvanized sheet metal that has been put through a phosphate bath and chromate drying process leaving it ready to accept paint, and is used for downspout, gutter and other applications.

Bonderize means:
Coat with a substance that will prevent corrosion.


Therefore Todd's definition could well be accurate.
LOL. It's been more than two years since the original post and I still don't know for certain what "bonderize" is! Oh well!
my research aligns with your statements. what are your credentials or references.
This is pretty wild that folks are dragging up this very old post. Something is driving us to it.

A phosphate bath and chromate pre-treat as Greg mentioned is a way of prepping metal to receive paint. In most coatings systems, this is a precursor to a primer paint coating.

I am unaware of anyone selling metal that has only had these processes done and has not had primer applied. Does not mean its out there but, if it is out there, I am not sure I'd want to work with it due to the small risk of chromate remaining on the surface and not having a primer in place to protect those handling the metal.
it's out there in GARY,IN.
Someone can make something and call it anything. I have to side with Todd. I think I'll take galvanized steel and coat it with an elastomeric and call it rubberized steel.
I do have a customer looking for this material, prime phosphate bonderized sheets. 11 & 13 gauge. Where in Gary did you find it?
I would appreciate your help!
That is some really heavy stuff. I might check with a steel distributor such as Ryerson or the like.
Thanks Todd, I'll try them.
good luck
We use it WITHOUT a final coat for the insulation jacketing of oil pipelines in Alaska (but only in 24 gauge). Apparently some hippie spoke to the caribou and they said they don't like the typical shiny stuff in their tundra.
I used to be in the steel coating and lithograph buiseness. Bonderized steel looks like what we called black steel, and If I rember correctly this metal had a crome coating in lieu of a galvanized coating. Not sure it it's the same and the old memory ain't what it used to be.
You can buy 24x36" sheets of it at Home Depot now. One store also had what appeared to be 25ft. rolls of it, 10-12" wide. It has a slightly blackened appearance to it. I'm making a guitar pickguard out of it.
I work for a supplier who carries 24ga 4x10's in bonderized.

Here is a brochure on the material -

Wow. Thanks.
How funny!

A contractor (Los Angeles) just informed me the metal will be "bonderized". Having no clue what it meant, I came here for answers to the apparent 4 year question!

Pretty much what I thought.
Bonderized is what we roofers call paint grip metal. It has a dull primer bonded to the metal. It is meant to be painted and it holds paint quite well. We make flashings (mostly wall flashings) out of it so that it can be painted to match siding. We also make copings for parapet walls out of it so that the building owner can paint it to match the decor of the exterior of a building.
Matthews Roofing
The company I work for has started using this "Paint Grip" metal for lighting products. We are using straight Muriatic Acid to aid in the solder process to allow the solder to actually stick. Does anyone know of another product to make this solder stick more readily? Next question is, After soldering How does one deoxidize the metal and what type of primer is needed to make paints stick????? We have a job that we painted (Hammerite) but did not prime and the paint is peeling off in large pieces.
Did you manage to find the correct primer for hammerite?
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