There is a good book on vacuum bagging. Its "RADIO CONTROL FOAM MODELING" by David Thomas.
It describes how to make a vacuum pump out of a discarded refrigerator pump.
It also describes how to make the press DH refers to.
The book is published in England but I found it in a US hobby shop so it must be available thru our destributors.
If you can't find it PM me and I will send the publishers address