I am shipping this metal wall sculpture to San Clemente tomorrow. It has a remarkable patina, beautiful blues and greens and browns.
This is one of my layered puzzle designs that I have been doing since 2000. This metal wall sculpture was originally designed to be mounted on a circle, but that design was very heavy – about 75 lbs. This design works very well without the circle. This metal wall sculpture has 12 pieces, each 2″ wide, made from two sets of 22″ squares with the next smaller square cut from inside the larger square.The smallest pieces are 2″x2″ squares – a little hard to see in the photo, but they add that je ne sais quoi.
Metal Wall Sculpture – Preparatory Steps
To begin, I laminated .020 pure copper to 1/4″ 5052-H32 aluminum with two coats of Weldwood contact cement applied with a roller. I applied the first coat, then let it completely dry for 24 hours before applying the 2nd coat. This works very well. Three coats of glue does not seem to adhere as well as two coats.
The secret to waterjet cutting these laminates is to place the copper side down while cutting. This works because the copper is thinner and much softer than the aluminum. If they are cut with the copper side up, the high pressure stream pierces the copper then hits the aluminum and blasts out in a 360 degree radius while piercing the aluminum. This may only take 1/10 of a second, but the high pressure stream finds weak areas in the glue and effectively delaminates the composite, which then requires a lot of gluing and clamping to repair it.
Inevitably, some repair is required. I use 3M 2-part urethane epoxy 190 and clamp it tightly for an overnight cure. The next day I cut off the excess glue with a razor blade.
The next step is to do the layout. I lay the metal wall sculpture pieces out on a piece of clear mylar. It can take many iterations to get a good design – it used to take me days, now only hours. Since the design is on a table, I climb up on a step ladder to get a bird’s eye view. When I have the design I want, I trace the outlines with black marker, then flip the mylar and all the pieces upside down and redo the layout inverted. I then carefully clamp each piece to the next with a 90 degree angle brace. I then drill 3/32″ holes though the center of each intersections, being careful to pierce the top layer but only leave a mark on the next layer – the mark indicates where I will weld on the 1/4-20 aluminum nuts.
Next I weld on all the aluminum nuts with 4340 aluminum mig wire, including nuts for hangers and wall spacers. The welds need to be quickly cooled with water or they will warp badly. Also, the welded area can warm the glue enough to cause delamination , so I clamp each welded area as soon as possible to let the hot area cool down while it is clamped and reattach.
The patina ensues – the greens are usually created with Sculpt Nouveau’s Tiffany Green though I occasionally use some vinegar as well. The blue is with a special patina I mix up with lab-grade ammonia plus ammonium chloride. Patinas can take a week or more to develop. Usually I let it go for a day or two. When dry, I rinse it off, inspect it and reapply chemicals as needed. Sometimes I have to grind away the patina and start anew with fresh copper. Whatever it takes. When the patina is done, I spray it with Krylon Clear Triple Thick and let it dry 24 hours. Note: Lab Grade Ammonia is highly noxious to the eyes and lungs! Use protection and good ventilation!
Now I drill the holes to their full size – 5/16″ diameter to accept the 1/4-20 bolts. I need a little play for adjusting the pieces. I don’t do this earlier because that would let acid and water inside the holes, which adds an extra step to clean up.
Next I clean the edges of the metal wall sculpture pieces with a 3M 80 grit sanding pad on my grinder. Then I paint the edges with a latex brown paint that matches the copper brown patina. This usually takes several coats – at least 5 hours to do edges, including touch ups. But I love the way it looks. Then I clean the backs to a shiny aluminum color. People inspect the backs – you want everything to look perfect, even the parts that aren’t seen.
While I am finishing the edges, I also cuts spacers from 1/4″ aluminum tubing and paint them the same color as the edges. Usually these spacers are 1/2″, 1″, 1.5″. etc. depending on the number of layers.
Metal Wall Sculpture Assembly
Now the assembly of the metal wall sculpture. This is very high-focus work. I use 3M epoxy 460 on the nuts in place of loctite. I have had very bad luck with loctite – even the red high strength loctite has worked poorly for me. I get all the 1/4-20 bolts and spacers in place, but loose, not tightened down. Then I start checking angles and separation – I am going for an accuracy of 1/32″ because I know at some point I will end up being off 1/16″ somewhere, which isn’t so bad. A little wiggledy-woggledy makes the piece more mesmerizing. When I get two pieces lined up exactly, I torque the nuts down to 40 inch-pounds and move on to the next piece. I have to get all this done in 3-4 hours before the epoxy sets up too much. Get the hangers on, get the wall spacers on and let it sit over night. The 460 epoxy sets up to 60 inch-pounds, much stronger than any loctite I have tested.
It is a long way to California for a metal wall sculpture inside a crate in the back of a truck vibrating all the way there. Plus the crate is heavy and someone is bound to drop it. And the forklift boys are hard on these crates that aren’t on skids. But I think it will hold together with the 460 epoxy and 40 in-lb of torque on the nuts. The box is foam-lined and I am hoping for the best, as usual. What else can I do?
This metal wall sculpture ended up weighing 30 lbs. It has 4 layers and measures 43″ x 45″ x 2.5″. The box weighed 75 lbs (105# total) and will cost $153 to ship to Escondido via Fed Ex Ground.
Interesting back story to this metal wall sculpture. Originally it was ordered by a company in Newark, CA, just South of San Francisco. They said they wanted a green patina – no indication of what kind of green. So I shipped them this metal wall sculpture. Turned out it was the wrong green! They wanted a green to match their carpet! So they sent it back! But of course, they wouldn’t send me a sample – I had to send them a dozen samples of green patina and they finally picked the one that matched their carpet – an ugly brownish green! So now we know to send photos first and get approval before shipping. We used to just ship and everyone would love what they received. It’s a different world after the 2008 economic collapse and we have adjusted accordingly.
Well, the couple who chose this piece for their sun-filled home near the beach in San Clemente objected to some whitish areas on the patina and asked me to tone those down, which I did with multiple applications of transparent blue and black layers of Smart Coat plus numerous photos back and forth. They also wanted a matte finish. I preferred the semi-gloss, but I am a people pleaser, so I did as they asked.
The most common question I get from the non-artistic buying public is “how long did that take to make”. I’d guess this metal wall sculpture took about 40-50 hours, start to finish. It’s a labor of love. That’s why I do it.