Wednesday, June 15, 2011


Speaking of lab safety.... I spent the evening soldering up a copper connection between my Welch Duo-seal 1402 vacuum pump and the cheap Nalgene bell jar that was on the shelf when I got here. Now, I figured an old plastic vacuum chamber (circa 1989) might not be up to the task of withstanding the forces, so I took precautions. Namely, I was wearing PPE and had my camera handy. As the gauge drew nearer and nearer to 30inHg I grew more and more incredulous that I really did such a great soldering job in the first place and that seals weren't crumbling at all and the bell jar seemed to be holding up to the constantly increasing stresses while the tension in the room grew palpable, somewhat squishy though oddly unyielding, and as it passed 29inHg and crept ever closer, yes improbably still closer to thBAM!!!!!e baseplate imploded with a thunderous crack and blasted shards of brittle plastic far and wide (and into my noggin' and torso), and catapulted the bell jar through a series of somersaults in the opposite direction. I immediately pulled the plug on the pump, took some photos of the mess, and then flipped the camera around to see myself smiling through the face shield I was not-accidentally wearing. Damn good thing this test wasn't conducted with a pot of resin in it, eh? That wasn't an accident either, by Jove! So now, as the hour has drawn late, I plan to stop on my way home at the local tavern for an oat soda.
[Edit 6/16] A friend on Facebook asks Q: What makes the baseplate so shitty?
A:The baseplate isn't inherently shitty, just made of plastic. And plastic doesn't last worth a damn, even though we think it exceptionally clever to build everything out of plastic these days. This baseplate was probably 20 years old, and if I'd peeled up the stuck down gaskets I would have seen some crazing that wasn't visible from the bottom. I'm guessing that this is a result of not just age, but also resin fumes. Contrary to "The Graduate", plastics are not the future. They are a temporary present.

Shame on me for not taking a Before picture. This is, uh, After.
Why is it that only old guys wink any more? I think we should recapture the non-flirtatious wink.


1 comment:

Paleodigger said...

AWESOME!! You should invite people has a live audience to watch this..."experiments" :P (all wearing the adequate PPE i.e. A camera!! :P

Also that base place seems pretty week..