Cannon on my bench?

Hi Phil,

I think I'm done with the pyrotechnics for now while I still have my eyebrows.  But, I suspect you are right about the alcohol.  I'm still going to keep lacquer thinner around, but only for hand cleaning of small parts when necessary.  Flushing is going to be strictly mineral spirits.

Don

Hi Don,

I don't know if you're game to try another test, but I rather suspect something similar may happen with alcohol (as used with many acrylics). Liquid alcohol will ignite readily, so I suspect that vapourised alcohol may also react similarly.

Be careful if you do try this - as you may be aware, many alcohols burn with an invisible (or near invisible) flame.

Don Wheeler

put a dent in my ceiling and a stain in my shorts.

I appreciate that bit of humor!

Although good to know, I only use acrylics so don't have that worry.

Back in the day, a couple of us used to make "bombs" & "cannon's" with Sodium Chlorate weedkiller - add the correct amounts of sugar & carbon & it was pretty potent. We went from lighting pretty poor mixes of it on the ground, to making cannon's from cast drainpipe's. The secret to getting decent power out of it was to get the percentages spot on, grind the ingredients very fine & contain them in something reasonably strong that could withstand a decent pressure build up before exploding.

It was a bit like loading the guns on a battleship, in with this, in with that, in with the (charged) projectile, light it & cover your ears - sodium chlorate has now been banned in the EU.

As they say on Myth Busters, "Don't try this at home".  I can now say with some certainty, that there is an explosion risk here.

I put a Kleenex tissue across the top of my cleaning jug and held it in place with a rubber band.  My first test was with mineral spirits.  I filled my Patriot cup about half full of thinner and sprayed it into the jug through the little hole I normally use.  Then I quickly put on a full face mask that I use for wood turning and carried it outside.  I applied a flame from a long butane lighter, purchased for Halloween jack-o-lanterns, to the hole.  Nothing happened.  I even removed the tissue and stuck the flame inside; still nothing.

Then I repeated the test with lacquer thinner.  When the flame met the hole, there was a WHOOMPH, the tissue blew apart, and what was left caught on fire.  Before I could put it out, it partially melted the top of the jug.

So I have to conclude, if I had something like a filter firmly attached to the top of the jug, there would have been a possibly dangerous explosion.  Mineral spirits seem pretty safe, but not lacquer thinner.

This has caused me to re-think my choice of thinners.  I have always used lacquer thinner, but I believe I'm going to switch to mineral spirits for my enamels, both for thinning and clean-up.  I may have to re-adjust my technique a little, but I'll feel a little safer.

I you use a cleaning jug and lacquer thinner, please make sure that the top will pop off easily in case the fumes ignite.

Don