After (finally) dedicating “Wellspring” last week, I thought it was high time to post a wrap-up of how it came into being. I leveraged Rhino’s formidable toolset to model the entire thing in 3d on my computer.
Rhino includes some really powerful tools for “unrolling developable surfaces” – flattening out the curvy bits so they can be cut from sheet stock. I usually try to color code the parts so my simple mind has an easier time figuring out what goes where, which can become problematic when you’re dealing with over two hundred pieces like I was here. I also model the footing and whatever anchoring hardware are called for by the engineer. This way I can at least pretend I’ve planned for any possible issues that might pop up regarding clearances and installation logistics, plus it makes accounting for a bill of materials a lot more accurate.
Once I’ve got that all squared away, I export a file of the pattern in a format that the cutting job shop can use to drive their cutting machine – in this case, a water jet.
I also modeled the internal superstructure of 3″ stainless steel square tubing. Again, doing so insures that it fits properly within the base’s envelope, plus it allows me to produce most of the sketches needed by the engineer directly from the 3d information.
Once the modeling, unrolling, and pattern making are done, I get to sit around nervously while the parts are all cut out. Any mistakes can be costly at this point, and I did manage to skip a couple pieces on this one. Sorting and identifying all the parts can be daunting and confusing, especially if many of them are just slightly different from one another. I should probably implement a better part labeling system at some point, dontcha think?
Now it’s time for the real work to begin. I started with the 12 gauge parts of the base. One of the difficulties presented by working with stainless is temporarily holding the pieces in place in order to tack them together with the welder – 300 series stainless (this is 304) is non-magnetic, so the usual magnetic clamps are useless and mechanical ones have to suffice. They often don’t, requiring some fancy gymnastics, some Rube-Goldbergian jigs, or a combination of the two.
The surface of all that stainless also needs to have a nice handmade swirl applied. Below is the top of the base, which is 1/4 inch plate.
Here is the superstructure being welded up, and then with the 1/4 inch top included:
I then welded the aforementioned 12 gauge base sheets to the superstructure. Somehow, I’ve neglected to get a picture of the finished base before attaching it to the rest of the piece. Oops. With the base done, I moved on to the “frame” part of the sculpture, which is the outline of Adams County itself. I came to regret including all those jogs – which, BTW, is the part of the county that got chopped out to make Denver International Airport.
Next came the grass blades. I always like working on the curved parts, as they magically form themselves into the correct shape as you draw the edges together. Not so magical is the tranformation of the raw welded seams into nice clean corners. HOURS of grinding and honing, all by hand, all by yours truly. Weeeeeee.
After each blade is finished, it is added to the frame. The design is such that the grass blades act as stiffeners and reinforcements, adding lateral inegrity to the structure. In the pics below you can also see I’m test-fitting the mounting system for the acryllic circles – which represent an aerial view of center-point irrigation.
After attaching all three blades and welding up all the connections that were easily accessed from the top side, I needed to flip the whole thing over so I could do the same on the other side.
With all the welding and chasing (foundry ratspeak for grinding) done on the main upper portion of the sculpture, it’s time to attach the base. This was by far the most technically challenging aspect of the fabrication, as the alignment of the frame to the base determines the attitude and verticality of the whole works. PLUS, the base outweighs the rest by 2-to-1, throwing the center of gravity way off from its previous location and making rigging and picking the thing much more complicated. PLUS the welded connection between the two is structurally critical. Lining it all up:
Once the alignment is good and the top side welded, I needed to flip it again to access the base/frame connection on the other side:
And then weld that up:
With the welding, grinding, and swirling completed, I needed to attach the acryllic circles. I’d fretted a bit about managing this without scratching the material, but it ended up taking about an hour to finish up.
At this point, the fabrication is finished. Ta. Da.