Vacuum table Setup Advice

[GEOFFREY]

Surely for wood the bit needs to fully penetrate the work so therefore a sacrificial (mdf?) board is still required. What type of expanded plastic board do you use as most plastics are virtually impermeable, or do you use some kind of foam board (polystyrene?). G.

[Boyan Silyavski]

Surely for wood the bit needs to fully penetrate the work so therefore a sacrificial (mdf?) board is still required. What type of expanded plastic board do you use as most plastics are virtually impermeable, or do you use some kind of foam board (polystyrene?). G.

3-4mm expanded PVC, used usually as backing for large photo prints. have friends with photo studio and use for free the rests. its sth like 6euro per sq m , sold on sheets of 3x2m. Easily cut wit cutter/exacto knife/. One of my favorite materials.

also from them i get super strong ultra thin double tape sheet, used to stick photo prints to methacrylate. This i use on small pieces for fixing the center not to flap. very strong stuff, if used bigger is impossible to separate. if cutter passes through it though the last cut should be way slower.

If the machine is precise and the table is surfaced plastic or even better- some phenolic sheet, the bit does not need to penetrate more than 0 for wood and plastic.Its very pleasant to the eye how it cuts through and does not damage the surface. of course after auto 0 procedure, preferably using calibrated material touch plate.

Only for aluminum it needs to go deeper as its slightly pushes the last material instead of cuttingwhen set to cut to 0 depth.

[GEOFFREY]

Thanks Boyan. Your machine must be super accurate if you can cut through without marking the undersheet. I have a metal matrix table and neoprene gasket material is fed into the matrix slots to form the vacuum to the the areas where i want to cut. Under vacuum the gasket compresses, more or less flush to the bed, but not 100%. This would certainly preclude only cutting to the spoilboard top, and all the large flatbed routers that I have seen ALWAYS leave a witness mark of some description. G.

[JAZZCNC]

Thanks Boyan. Your machine must be super accurate if you can cut through without marking the undersheet. I have a metal matrix table and neoprene gasket material is fed into the matrix slots to form the vacuum to the the areas where i want to cut. Under vacuum the gasket compresses, more or less flush to the bed, but not 100%. This would certainly preclude only cutting to the spoilboard top, and all the large flatbed routers that I have seen ALWAYS leave a witness mark of some description. G.

This is why you need a thin permeable layer to allow cutting thru without marking base.

Boyan most the Ali plate I cut comes with plastic protection layer and this offers enough cut thru in most cases. I always use finish pass which helps remove most of the burr and then I De-bur anyway so doesn't really cause a problem.

[Boyan Silyavski]

Here is short video of the ebay pump. I went today to my friend and tried it. In Russian, we speak about the additional pieces and that obtaining the clamps from the seller is very important.. Now to have in mind that this is 7cfm pump at the same time only 0.37kw and very quiet. Its 3 phase so as you can see at the video. Definitely worth purchasing if sb is on a hunt for vacuum pump. All extra pieces are custom made.

https://photos.google.com/photo/AF1Q...jnfNiLBkTyDYMU

[andy_con]

wont let me view, says I need an account to view

Here is short video of the ebay pump. I went today to my friend and tried it. In Russian, we speak about the additional pieces and that obtaining the clamps from the seller is very important.. Now to have in mind that this is 7cfm pump at the same time only 0.37kw and very quiet. Its 3 phase so as you can see at the video. Definitely worth purchasing if sb is on a hunt for vacuum pump. All extra pieces are custom made.

https://photos.google.com/photo/AF1Q...jnfNiLBkTyDYMU

[Boyan Silyavski]

Here is the vid in YouTube now.



The connection and bracket are named KF25. plenty of them cheap in ebay.

What you will need more for the system:
-outlet- additional bracket and oil trap filter for the exhaust oil vapors, which is basically a box with sponge inside
-inlet- at least another bracket and hose adapter. Inline air filter at least 5 micron, so no dust enters the sucker. Maybe cheap car fuel filter or sth similar. Liquid separator?
-2 capacitors so you can run it 2 phase. its 3 phase originally. One for start and other to run, see video.

additional notes:
-I don't see a reason for an air reservoir as the system will be very tight and it will take time to achieve pressure with big deposit. Switch on, use and then switch off. This pump has nothing to do with the cheap ones/similar price new/ sold at ebay with similar ratings in CFM, though i believe even they will work ok as here the purpose is not removing the last atom...
-digital vacuum gauge is recommended, though even a analogue will work ok. i don't see actual need for switch except to make some sort of bleed valve when certain vacuum is reached. hopefully there will be some smallish leaks in the diy seal anyway, cause that thing is a sucker.

I am very inclined to grab one. If you are even more patient next week i will go there again, so can try it with some improvised vacuum fixture and make video of it.