Pouring steel at the Steel Yard
I didn’t appreciate how entertaining it could be to watch people work molten metal, until I watched Robert Houllahan’s film of The Iron Guild pouring at The Steel Yard this Halloween.
Casting & Forging
Heart mold from homebrew silicone
Greg comments on his difficulties with the stiff consistency of the cornstarch / caulk mixture, which seems like a germane time to mention a comment on last night’s Oogoo post from W. Aaron Waychoff, who claims to have had success using glycerine as an additive instead of cornstarch. [Thanks, Greg, and Aaron!]
How-To: Make cheap castable silicone from caulk
Turns out, though, that mixing in some cornstarch accelerates the drying process; just how much depends on how much starch you add. The author recommends starting with a 1:1 mix. I’m not sure about his explanation that the process works because the hygroscopic starch carries moisture into the internal volume of the silicone, but in any case there are probably other additives that will accelerate the process as well as or better than cornstarch. You might even find one that’s not opaque and allows for translucent castings.
Printable molds for casting monolithic button arrays of any size
Josef Průša saw last week’s post about choosing a silicone for casting soft button arrays and pointed me to his printable mold for such arrays on Thingiverse. The model was produced in Clifford Wolf’s awesome OpenSCAD 3D modeling package, and the .scad script is available for download with the Thing. It has been parametrized to produce molds of button arrays having any number of rows and columns–all you have to do is change two values. The individual buttons are sized to match the SparkFun 2×2 button pad used on the monome, and also include backside recesses for LEDs.
Choosing a silicone for casting soft buttons
MAKE pal Steve Cooley, who manufactures the Beatseqr hardware performance controller, has posted the lab notes from his recent experiments with various silicone products for casting monolithic soft button arrays. I love it when people do this–the steps and missteps that happen along the way are often as interesting, and as helpful, as the finished product.
How-To: Cast a solid ice beer caddy
Rob Cockerham–who has previously brought us spring shoes, a sweet Doc Ock costume, and How Much is Inside?, among other delights–wanted to serve a six-pack out of a solid block of ice. The block had to be cast with openings that would hold the bottles tightly but still let them slip loose when somebody wanted one. It took a bit of trial and error, but he eventually got the process figured out. The whole story is here. Rob hasn’t tried it yet, but he thinks, as I do, that one of these will probably float in a swimming pool fully loaded. Nice work, Rob! [via Boing Boing]
Gingery-style homemade metal lathe builds
Throw a stone at any gathering of makers, and you’re likely to hit somebody who owns a set of DIY-savant Dave Gingery’s classic books on building your own machine shop by casting scrap aluminum, melted in a charcoal-powered bucket furnace, into sand molds formed by wooden patterns. I’ve owned a set myself, for more than a decade, and “at least starting on the lathe,” which is the first tool in the series, has been on my someday list since the first time I ever saw the books advertised in Lindsay Technical Books’ classic ad in Popular Science.
