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View Full Version : Vacuum pump for a large matrix bed cnc 5 by 10 foot



gavztheouch
02-11-2013, 05:22 PM
Hi all,

I have been using screws to hold down my sheet material rather than vacuum, this works work but it is time consuming.

My router has a matrix table 5 by 10 foot and its all ready for a vacuum pump.

Has anyone had any experience installing a vacuum pump, I have heard they are difficult to get working well.

I am open to ideas other than the conventional vacuum pumps. I have seen people using milk parlor pumps and I have a slurry tanker on the farm which has a large rotary vane pump which is very similer to a cnc rotary vacuum pump. The problem with slurry pumps is they heat up fast and can only run for 5 mins at a time.

GEOFFREY
03-11-2013, 10:52 AM
Hi, I don't see why setting up a vac pump should be difficult to get working. As your machine is a commercial unit, the matrix bed should only require the pump connecting to the machine, and provided that the pump is large enough and the matrix bed seals to the sheet it works like magic - look Mum, no hands!! I have assumed that you are cutting dry and will use an MDF sacrificial board. A vacuum gauge at the machine end will allow you to check that the vacuum is sufficient, and I keep an eye on the guage reading to ensure that the cut items do not cause loss of vacuum. In most commercial applications there is probably an option in the post processor to allow you you select the vac option, and if the suction falls below a preset level to stop the program. If you intend to use that facility it may be a little more difficult to set up, but I would guess that you already have that facility, and that your machine is already just awaiting connection of a vac pump. In my case the hardest part was having to part with my hard earened cash to buy one! King creaky(forum member) was selling a couple of large pumps a short while ago and he was not looking for very much for them. I would guess that your slurry tanker pump is PTO driven and would not be suitable if you cannot keep it cool. Bite the bullet, get a decent sized pump, ensure the you get a good seal to your sacrificial MDF sheet (make several suction areas rather than just putting an "o" ring gasket to the perimeter) and you will wonder how you ever managed without it. Good luck. G.

gavztheouch
03-11-2013, 01:43 PM
Hi Geoffrey, thanks for the advice.

Can I ask how big is your table, what hp is the vacuum motor and do you use a blower style pump that moves a lot of air or a vacuum rotary pump which pulls a better vacuum but less air.

Cheers
Gav

GEOFFREY
03-11-2013, 03:00 PM
Hi Gav, sadly my cutting area is not as big as yours (working area about 2600mmx900mm) and I bought a used pump on ebay. My pump is Reitschle (or something like that - not in the workshop to check at the moment), but it is a rotary vacuum pump. The system does not need a huge air capacity as once the vacuum is formed it is only sustaining that vacuum plus any losses caused by the cutting. If cutting small items it is safer to "tab" them as it helps maintain the vacuum and stops them disappearing into the extraction system. G.

Edit. My pump is 5hp, but I would have preferred 7 - 10hp had I been able to source one. Only have vents open to the area you are going to cut as the MDF sacrificial board will leak vacuum. G.

andrewbond
03-11-2013, 06:01 PM
If you don't fancy busting out a couple of grand on a side channel pump you could try making something like this ... Black Box Vac Source - Let's Talk ShopBot (http://www.talkshopbot.com/forum/showthread.php?t=11813)

I use four small motors directly mounted to the bottom of my bed (one in each zone) works quite well, a bit noisy tho...

Want any more info pm me

Andrew