Vacuum table Setup Advice

[Boyan Silyavski]

As Dean says- be reasonable.

Now you know, the most important thing is to find the most sticky mat possible. I would go further and say that best result is a combination of screws and vacuum, hence, custom fixture for each part done in quantity. I also have thought to make the sticky thing from casting silicone gasket in shape if necessary

Not trying to sell, but if you have a total of 30 euros to spare, i can send you a slightly used brand pressure switch with digital pressure readout and analogue 5v output, which new goes for around 80-90euro at least. PSA4-102VP. I have 2 of them if sb needs. so you could use it to read negative pressure, switch on off compressor by relay / if additional deposit for vacuum, and so on...

as i said any 1hp-2hp air compressor, take out inlet filter and fit there vacuum hose. Usually 3/8" adapter. Rarely 1/4". At the output fit some connector so the compressor blows out at all time, without switching off. Furthermore a vacuum deposit made from propane bottle could be fitted between vacuum hose and air inlet, plus the switch could stop compressor when desired negative pressure achieved. So electricity is saved.

[andy_con]

ok so mat important, I may have to buy a few and test them. not a problem

screws are a no, if it cant be done 100% by the vacuum table then I wont be doing it. like I say part size is 250mm by 160mm by 5mm thick

id rather have the vacuum table completely separate from mach3. but thanks for the offer.
ok will see what compressor I can find for a cheap price. does the size of the tank on the compressor matter? or is it just the power that's important?

sorry but I don't get the purpose of the propane bottle? do I really need that?

As Dean says- be reasonable.

Now you know, the most important thing is to find the most sticky mat possible. I would go further and say that best result is a combination of screws and vacuum, hence, custom fixture for each part done in quantity. I also have thought to make the sticky thing from casting silicone gasket in shape if necessary

Not trying to sell, but if you have a total of 30 euros to spare, i can send you a slightly used brand pressure switch with digital pressure readout and analogue 5v output, which new goes for around 80-90euro at least. PSA4-102VP. I have 2 of them if sb needs. so you could use it to read negative pressure, switch on off compressor by relay / if additional deposit for vacuum, and so on...

as i said any 1hp-2hp air compressor, take out inlet filter and fit there vacuum hose. Usually 3/8" adapter. Rarely 1/4". At the output fit some connector so the compressor blows out at all time, without switching off. Furthermore a vacuum deposit made from propane bottle could be fitted between vacuum hose and air inlet, plus the switch could stop compressor when desired negative pressure achieved. So electricity is saved.

[andy_con]

would this compressor work for example?

http://www.screwfix.com/p/stanley-82...kit-240v/48089

[JAZZCNC]

You'll notice I'm not commenting on the Compressor setup and thats because I don't agree with it. Not saying it doesn't work it's just not correct way IMO and just a lottery to when it dies.!.

The better way is to have a dedicated Vaccum pump(or Generator) pull a Vacuum into reservoir tank that is strong enough to hold high vacuum pressure. Fit a Vacuum switch so pump is turned on / off has required. If used with good sealing practises then you'll hold small parts no problem.

The secret really is simply lowering the vacuum loss so often dedicated Jigs or Pods with unbroken Vacuum seal work best or the only way without getting silly on the Vacuum system.!! . . . Mats etc work but only to a point and the cutoff point will depend on part size and size/amount of cut-thru.

[andy_con]

So I'm assuming you would need an in and out for the reservoir tank?

So table in, compressor out (so to speak)

Still not sure I get the reservoir tank, so you just remove all the air from it, so it then wants to pull the air from the vacuum table and acts as suction for the table?

[GEOFFREY]

Just think of the reservoir as a storage system for the vacuum so that there is vacuum available sometimes when the demand would be greater than the instantaneous capacity of the pump. G.

[andy_con]

Ok cool

Are these any good

http://www.clampusystems.com/Venturi.html

Some claim 90% odd vacuum

Not saying they are a perfect solution but are they worth considering if you have a big enough compressor?

[JAZZCNC]

Ok cool

Are these any good

http://www.clampusystems.com/Venturi.html

Some claim 90% odd vacuum

Not saying they are a perfect solution but are they worth considering if you have a big enough compressor?

Yes they work good but again you need a Reservoir tank because they struggle to provide enough volume direct from the generator.
Having reserve of vacuum is what you need for when vac loss happens. Otherwise you need a powerful vac pump.

Just think of it has the reverse of a compressor, you wouldn't try using air tools with no air in your tank because the pump would struggle to keep up with the demand. It's just the same but with negative pressure.! . . . Holes in your work piece are like having a high CFM air tool.!