what pump to use for vacuum bagging

[kiteguy]

my friend and i are trying to figure out how to make a vacuum bag pump out of a fridge pump but can't seem to understand how it all works. if anyone can explain it with pictures or what ever.our problem is the pump itself,not the bagging tecnique.what to hook up to the pump and where on the pump to hook up to is the question. thanks

[pdkite]

turn it on, put a hand on one of the tubes.

if you feel it sucking air in, that's prolly the sucking end. if its blowing air out, that's prolly the blowing end.

google like, "convert fridge pump for vacuum bagging" or something.

i just used this ghetto setup, worked for me

don't forget to post pics of the build/finished board here! always nice to see

happy building

[Kamikuza]

My LEI's pump has an in and an out hole to plug the tubing into ... but then you'd have to do it by hand!

EDIT : oh now I see this is in the board builders thread ... I thought maybe you were trying to pack it down for travel or something sorry!

[FredBGG]

Don't underestimate the value of a good pump.

First of all you need the vacume pump to run as long as 8 hours at a time.
If your pump fails you can end up throwind out a bunch of expensive material.

Second ... most low end vacuume pumps produce oil vapour and if that vapor gets on your building materials in the area you are working the material will be useless.
This oil vapor is also highly unheathy.

You also want a fast pump as the quicker you can crate the vacumm the better especially if you have had a glitch durring the layup.

I use very high end medical grade vaccume pumps that are two stage.
Mine retails at $ 5,000. However you can get these extreamey cheap on the used mediacal surplus market.

It is dead quiet, procudes absolutely no vapour, does not overheat. It also has a very very good.

Cheers

Fred

[frankm1960]

Here's a couple links I was looking at sometime ago.

http://www.berkut13.com/sucker.htm
http://www.dream-models.com/eco/vacuumpump.html

[jaros]

I am using fridge pump with great resaults and have build many boards with the same pump. Sometimes when it is a bit cold the pump was on for more than 24 hours without any problem. It produces mor than 0,8 negative pressure. Until now it has not let my down.
My fridge compressor has 4 tubes. Two are sucking the air in and two are blowing the air out. You must use both "intake" tubes.
The oil from the compressor is not the problem, since if a drop comes out, it comes out trough "blowing" hole and newer from the "intake" hole.
The vapor is also not a problem. When working with epoxy anyway it is best to work outside or in a good ventilated room and allways use the mask with fiters for organic matter.

I am sure a 5000$ pump works better, though....
Greetings,
Jaros

[zob]

Does a fridge compresor have to run non stop? Does it lose vacuum if you turn it off?
Do you have a membrane instaled like in the upper links?...

[jaros]

Hi,
It is the best if you make the switch which turns off the comperssor when the desired negative pressure is reached and turns it back on when the pressure rises again, like in the upper links. But I am to lazy to do that. I keep the compessor operating the whole time. I am making wood core boards only, so there is no worry to press the core to much.
Greetings,
Jaros

[lawless]

All these graphics relate to DIY fridge pump vacuum setups:

vacpump.jpg (63.38 KiB) Viewed 1659 times

vacuumpumpsetup.jpg (10.42 KiB) Viewed 1659 times

vacdia.gif (4.3 KiB) Viewed 1659 times

[zob]

tnx lawless!

where can I find this vacuum switch (what kind of shop?), what is it used for?