Hey, I've got this 100 ml size hemispherical Glas-Col heater. I actually took it apart, cleaned the wool and cloths, and sewed it back together. (This
was not simple or easy!)
Anyway, I should have paid more attention to the heating element, which had some crust left after I rinsed it, because it reeks when operating.
For a "burn-in" I boiled water with it for 4-5 hours. I could see (at night) a faint glow from the element, which I figure gives the max temp of ~450
C. The smell did not seem to diminish much. It smells like burning notebook paper (kak!). Perhaps reminiscent of papermill..
Should I just be patient and keep boiling water? Or perhaps soak the thing in acetone or something. Any help much appreciated.Magpie - 29-9-2006 at 19:51
I bought some Glas-Col heaters off eBay which also had something spilled on them. But I think it was just petroleum distillates so it wasn't hard to
burn off.
Since you say it is the element itself that is contaminated this seems like a tougher problem. All I can suggest is to turn up to high heat (as high
as you dare) and let it burn off the stink for as long as necessary, preferably outside, of course.BeerChloride - 29-9-2006 at 23:36
Ok I'll turn it up a little more and let it cook. Maybe with just a dry spare flask. I just don't want to scorch it, since that was the whole reason I
took it apart and sewed it up in the first place. leu - 30-9-2006 at 01:42
Quote:
I actually took it apart, cleaned the wool and cloths, and sewed it back together. (This was not simple or easy!)
Some of the members might be interested in more details about this operation such as what sort of thread was used BeerChloride - 30-9-2006 at 05:21
Ok, I snipped the outer stitching and undid the thread, keeping it intact. I reused it later. There's actually a couple feet of extra thread inside,
wound in a supporting loop the diameter of the vessel it's designed for. Now, I'm not sure if all the material is glass: it occured to me that it
might be asbestos. ?
If you take one apart, you'll see how it's made - there's the fabric on the bottom, the one on the top, and another one beneath that which the element
is stitched to. The bulk of the thing is formed from a blanket of fiberglass padding. All of the pieces are just circular, and the shape is formed
during the sewing.
I replaced the topmost fabric on mine using glass cloth used for doing fiberglass/epoxy resin reinforcement. It's not nearly as dense as the original
fabric, though, so I doubled it.
I was actually able to get brown stains completely out of the original material using a mixture of bleach and phosphoric acid ("naval jelly"). It
releases some chlorine, but I didn't need to use much. The padding holds a lot of water, so I squished it in a towel (which I later threw away) and
then baked it in the oven.
Putting the thing back together was a mess. I definitely wore a dust mask. And later I realized that tiny airborn fibers had dispersed all around my
assembly area.
So using the original thread, I sewed it in the manner it was originally sewn (more or less..). It seemed like a disaster at first, but I was
pleasantly surprised when it took shape from the first sewing (sewing the element piece to the bottom piece). It helped alot to use a proper size
flask as a mold during assembly. Now the hardest thing about it was the 2nd final sewing, because the fabric edge has to be tucked under, and the
folded edge sewn in, while keeping the proportions right. I'm still not sure how I would do that step again. Maybe temporarily taping it, undoing the
tape as you sew.
It actually turned out better than I thought, but not REAL pretty - it does take some crafting skill, but definitely useable. The final thing I found
was that it was covered in fiber dust. I wish I had compressed air. But I just kept working with it, and patted it with tape (don't use very sticky
tape or it WILL pull and break fibers). Then I flame polished it with a propane torch. Very quick scans with the torch, or the material will brown.
Lesson learned: if you go through all that, make sure the heating element is clean!