I’ve always used EtOH to remove oil residue, then flushed with excess H20 and soap. I don’t seem to see a lot of cross contamination. Do others avoid simple methods like this? I haven’t run into problems yet.
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Soap should never be used to clean glassware. Soap scum is a contaminate, better is to use a lab grade detergent.
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Acetone, salt if necessary. Distilled water in a steam cleaner setup i have that @Photon_noir turned me on to.
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I’be done some weird experiments that require more aggressive cleaning methods, but generally, soaking in ethanol, maybe a light scrubbing, and rinsing with fresh ethanol in an angle-necked sprayer works well.
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Just boil glass with ethanol a few times and that should get rid of your pesticide problem
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I went and bought a large kiln.
I remove as much of the waste as possible, flush with ethanol. Then I put it it in my oven. Let it slowly ramp up to 565c. It’s hold that temp for 2 hours then slowly cools off.
In the morning I have nice clean glass.
You ever get breakage or stress from heat cycling? Have you got a polariscope? Have you looked at the stress regions before and after? I am interested in this cleaning method.
http://www.davebross.com/GlassTech/polariscope.html
Cheap glass will sometimes break. At 565c it re aneals the glass and removes all of the built up stress. Our processes, especially a short path create localized stress areas in the glass due to the fact that the entire glass piece does not heat evenly.
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Do you did any distortion in the ground glass?
That’s a good method to deal with the stess. I’ve had old boiling flasks break like candy glass.
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With ceramic and any crystalline/glassy material for that matter, annealing at an elevated temp for some time allows the individual domains at a microscopic level to align and relieve any built up stress. Annealing at higher temps reduces the amount of time needed to relieve this stress as long as you do not hit the softening point of the glass (2/3 of the melting point temperature). This is common practice in computer materials research where stress has large implications.
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So far I have had no sagging of round bottom flasks,
Make sure your kiln is vented to outside, it will smoke a bit. I have mine programmed to turn on at 9pm and run when everybody is out of the building. We have had great results with this process and my lab techs love not cleaning my boiling flasks. a 20L is a bitch to clean.
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I’ll say, how many 20l can you fit?
I can fit 3 in mine, but I only clean one at a time. Just in case things go bad
If you look on Craigslist you can find large Kilns for almost free… I bought a very large one that is computer controlled for only $600
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Damn skippy, thanks for the low down!
I may have to try this kiln idea… athough it may push me to start making glass because id have a piece of the puzzle
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Still no glassbower?I have some recommendations for california.
Tom at techni glass in Windsor ca fixes all of my glass for me.
707-838-3325
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No thats not the issue. The current one and the one issue ove had the whole time is capital. To start the project i need quite a bit and other projects keep getting in the way
I admire the do it yourself attitude. I’m right there with you, although currently I’m too busy to pick up that trade lol. I outsource glass, if it’s stainless, ptfe, electronic,or whatever else we make it here. Although a kiln as @TeachandTech recommended is certainly worth a try. You wanna make me some cows with a spherical vaccum takeoff to test out my spherical kf adapter? I’d have @Indofab rep it on his gram?