Hand Boilers

Dragonharper · #1 2012-12-02, 4:25am

Any one ever make one of these?

http://www.youtube.com/watch?v=GB916OHfFiU

It looks like it should to fairly simple to do. In the simplest form blow a bulb for the bottom, remove the tube. Cork the tubing, blow a ball for the top. Attach to the bottom bulb with a ring seal and let cool. Add some ethyl alcohol and some dye, then seal the top. DO NOT ANNEAL!

istandalone24/7 · #2 2012-12-02, 6:40am

haha. i used to have one of those when i was a kid....so fun to play with.
thanks for the link!

menty666 · #3 2012-12-02, 8:04am

Might be fun to try. Just be careful, that volatile alcohol's flammable.

Dragonharper · #4 2012-12-02, 8:22am

Quote:

Originally Posted by menty666

Might be fun to try. Just be careful, that volatile alcohol's flammable.

Ehtyl Alcohol (aka Ethanol) is very flammable (also available as denatured alcohol). However, if I fill the bulb correctly there should be very little air in the final assembly, just alcohol vapors, which will not burn without oxygen.

I've been thinking that one could also assemble the the piece, and leave a bit of tubing on the top, and anneal the assembly before filling. Leaving only the sealed bit at the top under stress.

wickedglass · #5 2012-12-02, 5:02pm

Methylene Chloride is the liquid most commonly used for these and you can use food colouring to colour it. Methylene Chloride, aka Dichloromethane, is paint stripper by another name. Dry ice will freeze it so you can seal it without much trouble, but you will also need to introduce a vacuum via a pump through the tubulation at the top seal. Using lightwall glass will reduce the risk of strain and you can seal it more safely without annealing, the thicker the glass of the seal at the top, the more risk of it cracking there is. This is why the glass in most love thermometers is so thin ... also to facilitate faster transfer of heat, but mostly because of strain issues.
You can also make drinking birds using this technique, you will need to flock the head so the water has something to soak into and evaporate from.

Dragonharper · #6 2012-12-03, 4:11am

Thanks for the info. How strong of a vacuum will I need to pull?

laserglass · #7 2012-12-03, 6:27am

you need to pull a vacuum inside this piece before you seal it off, so that it takes body temperature to boil.....i have a vacuum pump that connects up to a water faucet....as you run water through it, it pulls a vacuum on a side port....this is good as the alcohol vapors go down the drain....i also have more conventional vacuum pumps but you need to build a cold trap to capture the alcohol vapors which can be dangerous....

wickedglass · #8 2012-12-03, 7:41am

Glass pumps are the shizzle.
I use a mechanical pump, I don't have much space to keep a diffusion pump set up or want to use a water driven one, we recently broke a 10 year drought over here. The cold trap is a good safety measure for mechanical pumps, as they get hot. Freezing the alcohol in dry ice will prevent it from evaporating and producing fumes, but it's better to be cautious. If you can make a bubbler, you can make a cold trap.

As to the depth of the vacuum, my pump goes down to something like 3 torr. It's a pump out of an electron microscope, but you should be able to find a cheap single stage refrigeration vac pump relatively cheaply on eb that will do the job. It's not necessary to go down as deep as my pump does (I use mine mostly for plasma pieces), but the deeper the vacuum, the more effective the result. You'll also need to consider the strength of your vessel, if it's thin, a really deep vacuum may collapse it.

menty666 · #9 2012-12-03, 8:02am

I picked up a manual bleeder pump the other day to do something similar for another project. I'm hoping it works because the next step up was a 100.00 mechanical pump that didn't even include the hoses.

Given the size of what I'm making, I shouldn't need anything *too* intense.

Or maybe I will...we'll see LOL

laserglass · #10 2012-12-04, 7:17am

a diffusion pump is not required....it would not do anything because of the high vapor pressure of alcohol!!!! you can make a real cheap vacuum pump by using the compressor from an old refrigerator or air compressor in reverse. the water one is best, and you can capture all of the water in a sink so there is no waste.

wickedglass · #11 2012-12-04, 5:27pm

I get your point, but I refer you once again to my mentioning freezing the alcohol on dry ice. No vapor, no evaporation, no positive pressure from fumes, so a diff pump does work in this situation. I did, however, forget to mention that a roughing pump to draw a partial vacuum is needed to get a diff pump to work effectively.
But you're right, a diff pump is not necessary and it'll give a vacuum that's deeper than required. I just mentioned it because because the options I mentioned in my post above are what I personally have in hand and because of the water issue with water pumps and not wanting to be stuck with a sink full of water.

greymatter glass · #12 2012-12-05, 12:22pm

seems it would be better, and not too much more difficult, to draw the vacuum then introduce the Methyl Chloride via a syringe or stopcock manifold...no vapor problems at all then. I mean, if we're playing with vacuum pumps and dry ice, and other dangerous chemicals, we should have enough technical smarts to figure out a simple filling manifold...