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Thanks for your input.

Now my question, but first one final tangent:

I’m a woodworker and do marquetry. I use veneers that are .6 and .3 mm s in thickness, and I dye these to assure color permanence. I have a vacuum pump that will pull around 24” of mercury and sometimes I use that to force the dye all the way through the wood. I hate the noise that pump makes,so I’ve adopted another method.

The new method involves quart mason jars 3/4 full of dye,into which I plunge the veneer. Then I put the jar in the microwave to heat the dye. Once the dye is boiling I put the lid on it and screw the ring tight and take everything out of the kitchen (I always do this when the wife is out). Then I stash the sealed jars and forget about them for a few hours.

When I return to my jar stash, they’ve cooled to room temp and created a vacuum that infuses the veneers with the dyes. This method is just as reliable the vacuum pump.

I’ve been trying to figure out how much vacuum pressure is in those jars once the water cools to around 70f. I know some of it is caused by the liquid, but most is due to vapor condensation— in other words, the 8 ounce empty volume is creating most of the vacuum.

Would anybody care to take the time, or suggest where I could find the info? Yes, I ought to know this, but I was probably asleep that day in school...

Good question. You’re pulling 24” Hg of vacuum and then allowing it cool which will increase the vacuum but by how much?

You need the GayLussac Law for the answer.

The expression Gay-Lussac’s law is used for each of the two relationships named after the French chemist Joseph Louis Gay-Lussac and which concern the properties of gases, though it is more usually applied to his law of combining volumes, the first listed here. The first law relates to volumes before and after a chemical reaction while the second concerns the pressure and temperature relationship for a sample of gas often known as Amontons’ Law.
http://en.wikipedia.org/wiki/Gay-Lussac%27s_law#Pressure-temperature_law

Pretty easy to figure out once you know the boiling temperature where you live.

I could work this out for you... if I had all the unknowns... which h there are many.

An easy model would be to assume that the gas in the mason jar is 100% saturated steam at 212 degrees F. After capping the jar, the steam cools and condenses to a liquid.

I the thing to consider is the unknowns... like... what is the actual mix of air and steam... what is the actual temperature of the gas... the liquid... what gas volume is lost when the lid deform inward... how does the volume of the jar change when cooled?

How about we just accept that it works and have a beer instead?