Thread: Vacuum table Setup Advice
What your cutting also plays a big part here.!
That setup Lee linked to is great for wood etc with larger area and he's made a cracking job of it. But with small parts and high cutting forces on material like Ali or steel then it would struggle I reckon.
It's horses for courses really. If your cutting hard materials then you'll need good well sealed high vacuum and/or select your cutting parameters carefully.
am I right in saying all I do is connect the vacuum table to where the compressor sucks air into to fill up, open the oil drain value (which releases air from the compressor) turn the compressor on and it have suction?
I just need to find a good balance between the amount of air coming out of the compressor and the amount being sucked in?
so would something like this do
Really with small parts then vacuum is only any good if you have dedicated jig that will hold full high vacuum in areas of the parts that don't cut thru.
End of the day it's logical if you think about it. Surface area is the key, so if the part is small there's much less area to hold onto so higher vacuum pressure is required to hold it but less volume needed. Large parts have more surface area so a lower vacuum pressure can hold it because there's more to hold onto. Start cutting thru and large area then volume of vacuum required is more but cut too much and at some point the pressure will drop and you'll loose grip.
First there is a high power Vac pump or system designed to cope with the vacuum loss doing the sucking. The Vac table is a high Density hole pattern table type optimised for holding small parts. Then you have fact they are using special permeable Matt systems like VillMill which has a adhesize layer to help hold it down and distribute suction evenly.
Then quality 60,000rpm spinlde taking relatively small DOC at high feeds rates with quality Carbide tooling connected to a sophisticated cooling system greatly helping ease things along.!
Now I'm not saying milling small parts can't be done but it is a different ball game to larger pieces with more surface area so requires certain methods to be employed. Or Buy expensive Vacuum systems like Datron offer designed to cope with it.!
Can't just throw it on standard table with relatively low pressure sucking directly from the pump then cut thru it or take heavy cuts and not expect it move.
If it was that easy we'd all just use Henry's and Vacuum table for holding every thing.!!
Last edited by JAZZCNC; 09-09-2015 at 09:03 AM.
Im well aware datron stuff is in a different league, I have their price list and know how expensive the kit is
am I right in saying all I do is connect the vacuum table to where the compressor sucks air into to fill up, open the oil drain value (which releases air from the compressor) turn the compressor on and i have suction?
I just need to find a good balance between the amount of air coming out of the compressor and the amount being sucked in? Or buy that digital gage
so would something like this do
How do I work out if a compressor will give me the required suction?
Vacuum tables UK sells mats without holes in, so could this be another possible improvement?
Last edited by andy_con; 09-09-2015 at 11:21 AM.
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.
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?
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