Bronze for Sculptures – Silicon Bronze
I only use C65500 high silicon “A” sculpture bronze for my bronze sculptures, such as Dancing Fire #1 (image at right). It has a beautiful gold color, slightly brownish. It can be patinated like copper from light tan to browns, blacks, all manner of greens, reds, blues: in fact, any color imaginable. But why? It is such a beautiful color. I like to celebrate its natural beauty. Coated with the proper outdoor-grade lacquer and the clear coat will last 10-20 years.
Mig Welding Aluminum Problem – Black Powder Residue
I had a struggle recently trying to solve a mig welding aluminum problem. I do a lot of aluminum mig welding, primarily with 4043 wire and always wonder, what is that black powdery residue on the edges of the weld? Was it soot? If so, where would the carbon be coming from? Was the argon sucking in carbon dioxide from the atmosphere (venturi principle) and contaminating the weld?
Which Stainless Steel to Choose?
- I prefer 304, a low-carbon, austentic stainless steel for stainless steel sculptures. 304 is the primary stainless steel used for sculptures, architecture, manufacturing, etc. 304’s composition provides a better structural advantage and durability over 316, in most cases, as well as being less expensive.
- I am usually planning to weld the stainless steel and choose 304L, the low carbon version of 304. 304 and 304L are both 18-8, i. e. 18% chromium and 8% nickel. 304L has a lower carbon content (.03% maximum) than 304 which minimizes carbide precipitation occuring when welding. Consequently, 304L can be used ‘as welded’ in severe corrosion environments and eliminates the need for annealing the metal
- I usually choose the 2B finish. The 2B finish is a mill finish, which is smooth and not the brushed finish commonly seen on kitchen appliances. I do a lot of shaping, hammering and welding of the metal, which mean I have to repair the surface and create my own finish.
- 316 looks exactly like 304 but has 2-3% molybdenum added for even greater resistance to oxidation and corrosion. 316 is the preferred metal for food preparation, breweries, pharmaceuticals, laboratory use, etc. and any containers or objects that require resistance to extreme environmental conditions such as salt water, halides and acids.
- Occasionally I will use the 201 alloy of stainless steel for non-fountain, indoor sculptures. 201 is 4.5% nickel, 7% manganese and 16.3% chromium – it looks the same as 304 but is less expensive. It has a lower level of chromium and nickel than 304 but more manganese. It’s about 30 percent stronger than 304 but has less corrosion resistant and is more difficult to form and weld than 304.