Article 1 -Vacuum Clamping and Gluing: Part1

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Article

Vacuum Clamping and Gluing System

(Made from instructions on JoeWoodworker.com)

http://www.joewoodworker.com/veneering/pumpsys-concept.htm

A weekend’s worth of work to create a fairly sophisticated vacuum system. Next, the veneering bag and a radius dish for vacuum gluing top and back plate bracing.

Construction Notes

The construction plans on the www.JoeWoodworker.com site were very straightforward. He lists the items required and allows you to purchase them directly from their sister site, www.VeneerSupplies.com. A few issues came up during construction that added a couple of extra hours of work and headache.

As suggested by JWW, I used MDF board for the housing. In my haste to assemble the system, I tried to drill directly into the side of the MDF without a started hole. The obvious happened and the board split. I quickly learned from that mistake and used undersized starter holes for the rest of the attachment locations. If you decide to use MDF this way, be sure to have plenty of penetration as fasteners in the side of MDF tend to pullout easily. I would rather have used L-brackets to hold firm the perpendicular connections, but I didn't have any handy and I was eager to finish.

After the system was completely assembled, it was ready to test. The wiring instructions on JWW again are clean and easy to follow. I wired it up, plugged in the pump and, alas, it started up! I plugged the end of the hose with my finger to allow the air to evacuate from the reservoir tanks. The vacuum gauge began to register, but to my disappointment, the system shut down at 4 in Hg. I assumed I had wired incorrectly or ruined a part. I spin my wheels for a couple of hours checking wiring and connections. I finally put on my engineering hat and figured out the problem. The vacuum controller is adjustable, but comes at the lowest setting. (It probably says this clearly in the instruction pamphlet but who has time for reading, especially after a couple cups of coffee!) It was set to shut down at 4 in Hg and the restart was probably to low to start up again. I adjusted the knob until it shut down at the desired 24 in Hg and the system worked like a charm, cycling between 21-24 in Hg. I left the vacuum contained in the system overnight to test it and in the morning it was still at 23 in Hg.

Overall, the system works great and was fairly easy to assemble. I ordered everything from www.VeneerSupplies.com, which had acceptable prices. I did buy the vacuum pump used on Ebay since new ones can really drive the overall price up. I found a Gast pump that pulls up to 27 in Hg and 3.3 cfm for around $100. It seems to work perfectly and I look forward to using it!