Bronze plate

[E.Larson]

I am about to start my first welded metal sculpture. I would like to know if silicone bronze plate is what I want and would it be better to weld or braze this metal. Also, the sculpture is going to be a large 3D wall peice. (exterior) What gauge would be best.
Eric Larson

[Jay Long]

Hi Eric, thought I would comment. Silicon Bronze is a very expensive metal, so thickness is a issue, If you are mounting this to a wall, then you can get away with thinner material, If it stands alone then it would need to support itself. Bronze is a heavy material.
Myself I weld this material with the tig process, however I do believe that you can wire weld this material, I have never brazed this stuff, so I dont know if this would suit your needs. Jay

[E.Larson]

Thanks for the help Jay. As I said, this is new to me. Could you recommend an alternative to the bronze?

[grommet]

How about something cheap? I don't know what your funds are or what your piece looks like, but a nice cheap place to start is at the scrap yard. Steel is easier to weld than aluminum. Save the fancy stuff for after you master a good butt weld. Just the opinion of someone who would like to try all the toys and build this really cool thing, if only I had... (fill in the blank). :rolleyes:

[Jay Long]

Hey Eric, Jay again. I see you are from Alaska, myself I have been to Alaska many times, and have worked as a boat machanic, fabricator, welder, etc, If you are around any fish processing plants, They usually have a bone yard( scrap yard) and there is a lot of stainless steel laying around, this stuff is cheaper than bronze, and will out last it in the elements. however it is harder to fabricate because of its chrome content, however you can stick weld this stuff pretty easy, anyway if you could describe what you are going to build a little more in detail, how big? how tall? how wide?. I might be able to tell you more of what I would do in that situation. Jay

[EJB]

The main difference in the result of weld versus braze is the color difference at the connection. Since brazing involves a dissimilar alloy, it will oxidize differently from the base metal. Another thing to consider is exposure to outdoor elements. A weld (with the same alloy) will last much longer than a brazed or soldered joint. As far as the base metal, I would use whatever is readily available and in your budget. Yeah, the bronze is expensive. If it is your first project of this nature I would definitley consider using what works best with the equipment you already have. Bronze, stainless and mild steel work easily with a MIG welder (provided you have the right shielding gas and wire). Oxy/Acetlyne torch will give you tremendous heat distortion on thin gauge. TIG is perhaps most versitile and cleanest, again with the right gas. If the piece is to be installed indoors, you can get a nice bronze-looking finish on mild steel which is the most inexpensive and forgiving material. Often readily available new or as scrap. I hope I'm not being too elementary here to suggest that you first do a mock-up in cardboard to finalize your idea, then you can use the cardboard pieces for templates to make your finished piece without using up a lot of valuable time and material on changes.

[jOe~]

EJB, so how do you get a nice bronze-looking finish on steel?
Always looking for new finishes thanks, Joe

[E.Larson]

If I did this right there is a photo attached of the project I'm considering. I know, I'm nuts, but I have a tendency to think big. I have always wanted to do something like this and don't want to pass up the opportunity. I considered bronze because I thought this piece needed an interesting patina. I'm in southeast Alaska so the environment is pretty punishing so needs to be a metal that will hold up. So what do you think? Where in Alaska?
Eric

[Jay Long]

Kodiak, King Cove, Egigik, Dillingham, Dutch Harbor, Not to mention some overnighters in Anchorage because of foul weather. From what you have pictured, you could use a 14 ga in bronze and it would be just fine, however you might consider winds if you live along the coast, so attaching it to you structure would be a key point. Stainless would give you a metallic look that would probably last longer in the long run. Bronze would slowly get darker over time and if it is exposed to salt, it would probably speed the darkening process up. Anyway it looks like a pretty cool project. Jay

[EJB]

Ohhhhh-Kayyyyyyyy......ambitious indeed if you've not done large scale before but very doable with a good sized budget for materials. I would agree with your first coice of bronze. It will weather the seasons and look good as the patina changes. The weight would be considerable. In my estimation you would probably not want to go any thinner than say 10ga. which is roughly 1/8". any less and the wobble factor and distortion could be a problem. The thicker you go there is more weight to consider. I would also give serious consideration to the number and location of attatchments to the building to keep it from flying off in a serious wind. I would also recommend the attatchments be in stainless steel as well as any mounting bolts. Bronze is very durable out of doors but not completely weather proof. Expect 'The Green Streak' where water runs off of the piece onto the wall and the ground below. Mild steel would be a preservation nightmare, stainless or aluminum would work well but very difficult to get a bronze like color that will stick over the long haul.
In response to Joe's question about bronze look on mild steel....I've gotten variable results from using a base of ferric nitrate, followed by cupric chloride and/or cupric nitrate, then always a good clear coat and waxing. NOTE: This does not hold up very well out of doors where rusting will eventually occur.
There are also many ready made 'patinas in a bottle' available at many metal suppliers and sculpture supply houses.

[EJB]

P.S. Don't forget about snow loading!!!

[warren01]

Eric,
just curious since you are talking 3D how do you plan on shaping the metal...........any metal.

Bronze will hammer shape some but you need to anneal and can also work hot. The size you are talking about would require a lot of heat and tools for forming.

If more of a 2D piece you could cut out the pieces and do very little forming.

You can braze bronze but will show. But again the heat you would need lots of work. I would not make under 1/8 in thick. The weight would be about 4 lbs per square foot of material. So how big of shop and how well equipped would be more concern than welding.

Try making one about 3 ft in size just to get the feel of how hard it is to form the metal. You could use copper and tig weld.

warren

[stockon]

A more affordable alternative would be CORETEN steel. It weighs same as mild steel but is about 30% more cost. Still cheaper than bronze by long shot. It is used primarily for bridge construction and sculpture as a matter of fact. Much of Richard Serra's pcs are CORETEN. It has a wonderful patina and it is acheived very quickly.

Even cheaper is plain on mild steel-- which I use and do not coat at all. But in Alaska, it might not last too long if exposed to salt water/air.

CORETEN would however hold up.

If you do use Aluminum-- be careful in regards to your connections to the building. Aluminum to steel contacts are highly reactive and dont last without some kind of barrier.

Good luck.