Well a few days of milling and construction I have built a small frame press. The press is about 29 5/8” wide by 47 5/8” long and is 3/4” height of upper room. The unit is sitting on a 30” x 48” x1” thick melamine covered top. The picture shows the top on two aluminum stools. The press was made using an article from Joe Woodworker website. See details of building a frame press, links to parts and a good explanation on vacuum pressing on Joe Woodworker website
The frame is made from 3/4” thick x 2 1/2” wide solid Maple rails and stiles joined together using Kreg Jig joinery. The frame was sprayed with a couple of coats of Zinsser Bulls Eye Shellac before I added the poly top and wooden sealer strips. The top of the frame has a 3/8” x 1/8” vacuum gasket tape added around the parameter of the frame 1/2” in from the inside of the frame. A 20mil Poly sheet is then placed over the whole frame and wooden 3/4” x 1” strips are screwed through the poly and over the gasket tape to seal the poly to the frame. The excess plastic from the outside edge of the top wooden sealer strips to the outside edge of the frame press is cut off and a good bead of clear silicone is applied to the outside bottom edge of the wooden strips where they meet the frame press rails and stiles to further help seal the unit. Two rows of gasket tape are run around the underside of the frame, one near the front edge and once near the outside edge of the frame, to help seal the frame to a top surface the frame is placed on when in use. A hole is drilled through the side of the frame and a brass fitting is threaded through the hole. The fitting provides a way for the vacuum hose to be connected between the pump and frame. The vacuum hose from the pump to the frame is connected to the frame using a quick connect value. Once the vacuum process has been complete you simply remove the quick connection to the bag and the outside air flows in.
(I have made the testing room, my living room, which does provide easy access to seating for mulling over decisions and a much warmer environment than my garage which is around at 32 or 36 degrees F.
In the picture I have 4 small panels under a piece of 1/4” MDF which has a melamine covered side facing the top of the panels. The MDF has had all corners rounded over to prevent and sharp side puncturing the frame’s poly surface while in use. The panel and MDF combo is covered with a piece of “Breathing Mesh”, which provides a way to ensure that you can release the frame after the pressing. This setup prevents glue from getting on the bag and provides a good vacuum pressure distribution over the panels. The surface which you place the frame press on for the vacuuming operation, should be “flat” and “clean” and have a surface that will not allow air to go through or glue to stick to. In my case the melamine covered top.
The advantage of using the frame press is that you can apply glue to the substrate of you project fit the substrate to the top and bottom veneers and then place the frame over the whole thing and apply the vacuum. This eliminates having to do the same prep outside of a vacuum bag and then lifting open the bag. placing in the substrate and veneer sandwich and then closing the bag and applying the vacuum.
I will add there is a constraint on my setup, and that is the size of panel(s) I can press is restricted by the inside dimensions of the frame and a need to have space between project and side walls of frame. Also I can not exceed 3/4” to 7/8” above the table top surface the unit is mounted on.
However there still seems to be a small leak and I want to find it as the pump keeps recycling. Well back to finding a small leak which is going to be the challenge.
See you in the Workshop!