DIY vacuum pump

[TPink]

So the fridge at home recently died, wasn't cooling anymore.
Older unit, so instead of fixing we just bought a new one...

How hard is it to determine if the compressor pump is still good?

How hard is it to pull and assemble a vacuum pump for board building?
Was thinking a simple system w an old grill type propane tank.

Thanks!

[Rattlehead]

http://www.seabreeze.com.au/News/Windsu ... 93413.aspx

Built one pretty much the same as this one , used a vacuum advance off a car distributor connected to a micro switch ( which is adjustable) to regulate the vac pressure.

Thing works a treat.

[Bigdog]

Or just buy new. Safer solution and can run without a tank or pressure switch.

http://www.ebay.com/itm/3-CFM-1-4HP-Rot ... 53f811f373

[KerryBara]

There is lots of useful information on youtube

[Bille]

It's kinda Easy !!

I got a discarded refrigerator from the curb ; beat the
garbage man to it.

Next i pulled the, (120v) pump & compressor out of it .
Then i got a discarded beer-keg as a holding tank.
Got a vacuum switch, and relay from ACP :

http://www.acpsales.com/Vacuum-Switch-3 ... Range.html

Plummed it in brass, from Home-depot ; used a brass one-way valve
to keep the vacuum in the keg.

I bin using this devise for over 20 years now. I
spray WD-40 in the one-way valve, every time i use it.
I even got a hose from the pump ,to go outside ; now
i don't got to breath the epoxy fumes !

It runs about 5-min , an hour ; IF the bag is sealed tight .

Bille

[plummet]

I added an LPG bottle to mine as a vacuum reservoir. It helps with initial suck down speed and can extend the length of time between the pump switching on.

If I remember i'll upload a photo when i'm home.

[KiterDon]

Hi guys

I noticed the vacume pump Bigdog posted on this thread (the one on ebay). I've been experimenting with an old fridge vacume but have no way to regulate pressure and am drawing to almost one full atmosphere (about 26 psi on a car vacume guage).

My laminates are coming out dry-looking and the cloth is not going fully clear. I want a clear finish on a cedar core board and am wondering f I have too much vacume pressure?

Does that pump on ebay have a way of regulting the amount of pressure it exerts?

Thanks for your thoughts.

Don

[rynhardt]

[cleepa]

Hi guys

I noticed the vacume pump Bigdog posted on this thread (the one on ebay). I've been experimenting with an old fridge vacume but have no way to regulate pressure and am drawing to almost one full atmosphere (about 26 psi on a car vacume guage).

My laminates are coming out dry-looking and the cloth is not going fully clear. I want a clear finish on a cedar core board and am wondering f I have too much vacume pressure?

Does that pump on ebay have a way of regulting the amount of pressure it exerts?

Thanks for your thoughts.

Don

That seems like too much pressure. As far as I understand, about half that is what you should be using. If you add a vacuum reservoir with a pressure guage on it, you'll be easily able to control the pressure.

[kitexpert]

KiterDon, no way vac pump can draw too much of a vacuum for pressing. Real glueing presses use much stronger forces, equal of many atmosphere pressures.

But usually atm pressure is enough and it dont even need to be perfect vacuum. Frigde pump is actually more than enough, I tested one and it drew over 90% vac. That equals 4,5 tons of pressure if board area is 0,5m2, for perfect vac it would be 5 tons.

26psi is 1,8 atm, that kind of pressure is not possible with vacuum.

If laminate looks dry it is not wetted properly. More resin and/or harder press would be my suggestion.