wow what a mess

[mikenieves]

The dry vac does not contribute towards the removal of moisture, guess what I have tried and tested the method. Moisture removal should always without exception be carried out before any resin injection system gets near the damage.

i used to be a ac&r tech and instructor in the military retired in 2004, and i can tell u for a fact that i or any ac tech in the field always vacum a closed system for two main reasons, check for leaks, and to remove moisture and dirt before recharing the system with freon, the same exact theroy applieds here.....

[Brent Deines]

The dry vac does not contribute towards the removal of moisture, guess what I have tried and tested the method. Moisture removal should always without exception be carried out before any resin injection system gets near the damage.

i used to be a ac&r tech and instructor in the military retired in 2004, and i can tell u for a fact that i or any ac tech in the field always vacum a closed system for two main reasons, check for leaks, and to remove moisture and dirt before recharing the system with freon, the same exact theroy applieds here.....

I understand your thought process here but a windshield repair is not necessarily a "closed system"; often there are cracks that come to the surface. Also, if you use the same tool to remove moisture that you use to inject resin it is quite likely the resin will become contaminated before it is ever injected into the break, unless of course it is thoroughly cleaned and dried between the moisture removal and resin injection steps. Correct me if I'm wrong but I don't think you store freon and water in the same container.

[screenman]

I can tell you that I have put moisture in a chip vacuumed it to the max and left it, 24 hours later the moisture is still there. I have performed this test many times over. Please explain why this happens.

So lets look at it another way, using a Mitty Vac this time with a clear tube and a mushroom adapter, place a few drops of water in the clear pipe, place the mushroom head on say a piece of glass and pump like mad, leave for say 24 hours and guess what. Yep! the water is still there in a state of total confusion not know where to go.

Please try the tests I have and let me know your results, if they are different to mine I will be extremely surprised. However I will be extremely happy for you to prove me wrong, as you know moisture is one of our biggest problems.

Now we all know that placing water in a vacuum lowers the boiling point of water, now we also know that when water turns into steam, which we also know is 1600 times the volume of water. So my question where does the steam go to in a closed or dryvac system system?

Believe me I am open to any suggestions at all on how to speed up the drying out of 2 inch star breaks and the such like.

Oops! forgot something else, when we use a vacuum we are often closing up the break, think of a bulls eye cone and you will get my thoughts.

[Brent Deines]

Screenman, my findings were the same as yours which is why I put away my vacuum pump back in the 80s and only pull it out to prove my point when this question comes up.

Here is another point to ponder. If a vacuum pump removes water, would it not also remove resin? Yet vacuum pumps in various configurations are commonly used to remove air but supposedly "not the resin". How the vacuum pump distinguishes between the fluids is a mystery to me.

[screenman]

You win, I cannot better that one, yet.