[big-div]

Hi all,

Starting to build a vacuum table for a 4x8 router, only going 4x4 for the vacuum table just for easy of use etc..

I've got a javac vacuum pump that was used in the air con industry, I was intending on using that but I am unsure it will be enough.

I'll mainly be using the table for half sheets of acrylic, cutting through the whole sheet, but not going though the bottom paper ( now that my tool probe works properly ). I was also intending of having 3 separate sections, going all the way down to A4 size for some engraving laminate i have.

I have bought 2 sheets of MDF that I will cut to make into the half table. One is 25mm thick ( Bottom ) other is 18mm ( Top)

So I have a few options, router channels in the middle of the table between the two halfs to channel the vacuum to a grid of holes above. On the top then have channels in a grid to accommodate a rubber cord for sealing around the edges of materials. This is my first thoughts and how I have planned it out so far. I see a few down falls with this idea though. Because I am using 3mm acrylic, I figured it would not be rigid enough to pull down the seal and id end up with a convex top. Also that I would always need at least a 95% seal to maintain proper vacuum, as the flow of this pump is small but has high pressure capabilities. Trying hold down engravers laminate probably would end up the same as the acrylic.

Next option would be to open the table up a bit and provide a bit of a plenum area. Drill a grid of holes up top. Leave the surface flat with no seal grid. No different sections. Use a shop vac arrangement instead of the vac pump. A few people I've seen have had good success with this, it was the way I wanted to do it originally, but as I own a vac pump I wasn't keen on making another purchase.

Are there any guru's floating about that could steer me in the right direction ? I'll attach my CAD file which I've started drawing which has all my channels and holes marked out. The drawing was intended for use with the vac pump. Also the channels would be routered with a 10mm half round bit, MDF would have also been sealed.

Cheers !