John,

Normally, I would agree with you 100%. However there is no film on top when the can is opened and as you go lower and lower on the volume, the vacuum grows stronger and the last bit will not dispense without pressing on the can.

About all I can offer you is this: "Nevertheless, it revolves."

...........

Comments deleted



Edited 1 time(s). Last edit at 09/20/2016 05:19PM by John E Powell.

I never expected it to work, but it does. Quite well, in fact.

The laws of physics can't fail, but sometimes we don't apply them correctly. There is something else going on here but don't know what it is.

................

Comments deleted



Edited 1 time(s). Last edit at 09/20/2016 05:19PM by John E Powell.

I open the bottle, pour out what I think is enough. I then open the valve on my propane torch just a little and fill the PG bottle with propane. The gas is heavier than air so as it goes in the air is forced out. I screw the top on the bottle tightly, place it in a ziplock bag and stuff it in an old peanut butter jar with the PG bottle upside down and put it in the refrigerator, not frost free, and its ready for me the next time I need it. The bottle thats in there right now was bought at the ICRBE and opened the next day after I got home. I used some of it last week and it was still in good shape. I don't know if what I do helps or not but my PG last.

Comments deleted



Edited 1 time(s). Last edit at 09/20/2016 05:18PM by John E Powell.

Is the solvent is gassing off into the container, and filling the space with enough pressure to counteract the negative pressure (vacuum)???

George Forster
Fort Collins, CO

One thing for sure, be VERY careful when working with PG. A key ingredient is xylene. Proper ventilation, no flames, no skin contact is very important.

I just checked a post that I had previously made, regarding this very subject: August of 2007. At that time, my bottle of permagloss was 2 years old. 5 years later, I am still using the same bottle. I use a little on each rod, but apparently not much!

I keep it in the fridge, nestled in a jar of silica gel (which probably doesn't do much to help, anymore).

I just got interested in U-40 PG and have been keeping to the smaller containers as I 'experiment.' with the stuff.
I've been using one of those co2 dispenseser($12Innovations Ultraflate Plus CO2 --see link) to "displace the air with a heavier than air alternative".
I think it's a bit safer than propane.:) then it's back in the fridge.
Might be over kill but it seems to work.
I'll get a couple of those cans from Sammy Mickel at next years show.
Sammy bring more than you did last year!


[www.amazon.com]

John, I add a few drops of Xylene to the empty can and allow it to evaporate with the lid lightly on the can. I then fill the can with Perma Gloss and then fasten the lid on the can. When I remove some liquid from the can, a space is created above the can that becomes filled with the volatile components in the PermaGloss ( PermaGloss has a pretty strong odor and therefore it must have volatile components). Over time the amount of liquid in the can becomes sufficiently low that very little of the liquid will seep out. When this occurs, I place a light on the can for a few minutes and the increase in temperature cause an increase in the pressure of the gas which allows me to take out what I need for applying finish. My current can has been sealed for about two and half years and I will need a new can shortly. I also treat Lumiseal in the same manner. All you need to remember is if you have a gas in a confined space, the pressure will increase directly as the temperature increases.

Mike Blomme

FWIW, the physics involved in the PG can have been laid out in this thread. The PG flows out due to the weight of the fluid above the hole. As the volume decreases there is a bit of a vacuum forming above the PG. If you tried to empty the full can in one go, it wouldn't go so well, just like pouring gas out of an unvented can. But, since you are taking a small amount at a time, you have time scales between uses that allows thermodynamics to do its thing in reaching equilibrium. After you remove PG and close the can, some of the solvents in the PG will evaporate and create a vapor cloud above the PG (just like a gas can gets a vapor cloud above the gasoline). It is the time between uses that is the key to the PG can.

Mike pointed out one very useful trick. Molecules are moving around with random energies, and once in a while one gets kicked out of the liquid and becomes a gas molecule. Once it gets kicked out becoming a gas molecule, it is much less likely go back into the liquid (see the 2nd law of thermodynamics, also the reason eggs don't go back into their shells, etc.). Just like the vapor cloud in your gas can (plastic cans will visibly change shape) will expand and contract with temperature, the vapor cloud in the PG can will expand and contract with temp. If you warm the can just before you use it, you will increase the pressure and get better flow and get more PG out of the can in the end.

Joe

Amazing information on this product !

Rick H.

rwheil@msn.com

Website
[www.facebook.com]
[home.comcast.net]

I have used Perma Gloss in the past with great results. However I am trying to find out if this can be applied in cold weather as my garage is not heated. I do not have a well vented room indoors for this purpose.