Archive for June 12th, 2010

Casting Machinable Wax: Oops!

Remelted machinable wax

Remelted machinable wax

I put a new bag in the vacuum cleaner while machining the prototype case for the bike radio adapters, which was a Good Thing: the swarf from those two halves filled the entire bag!

I gutted the bag and dumped the swarf in a pot to melt down for another use. It started as a brick, but I figured having some rounds might come in handy. A bit of rummaging turned up some pill bottles of just about the right size.

Unfortunately, I didn’t think quite far enough ahead: notice the shoulder around the right-hand end of the shorter cylinder? Yeah, the bottom of the bottle was bigger than the top…

Fortunately, I don’t have a deep emotional attachment to the bottles, so carving it off the wax wasn’t a traumatic experience. Things would be different if I’d made a nice custom mold…

Of course, the vacuum cleaner also sucked up the odd screw, paper snippet, older swarf left in nooks and crannies, and some of this and a bit of that. Most of the junk either floats to the top or sinks to the bottom, leaving the rest of the wax in good shape. I suppose I could filter the melt, but it’s pretty thick & gooey, even at 300 °F, and I doubt my cheesecloth is up to the task.

Memo to Self: Do a better job of cleaning up before machining the wax, OK?