I want to start designing/building the table that my 1F elite foreman will sit on when it arrives.
I’m used to using vacuum tables on the CNC routers at my day job, so I am definitely going to invest in a vacuum hold down system either sooner or later.
I like what I see with the “AirWeights QCW Vacuum Slats - Foreman Complete System” to cover the whole 48"x48" area.
What must I consider when building the table for the 1F, so that I can easily upgrade and install one of those table vacuum systems? It seems pretty simple, but I just want to make sure that I prepare properly.
Is it necessary that I get a QCW frame to use this system? If not, how would I make it work?
My end goal is I would like to be able to put a 48"x48" flat sheet of material on the table and have the vacuum hold it. I am aware that it’s best to put a spoilboard on top, so I would use MDF to let the vacuum pull through, and then my material on top of that.
I’ve gone through the same debate myself. I tried to design my table to accept some kind of vacuum hold down system later on. My 48x48 Onefinity is up and running, and I’m trying to figure out the best way to add a vacuum table.
I believe the airweight systems just screws right down to whatever they are installed on. If your making your table yourself, the top surface is probably wood, which would make for an easy install.
I’ve wondered if the airweight system would work through MDF. The little compressor seems to hold very well when there is an excellent seal, but when a leak occurs clamping force diminishes quickly. My gut tells me the low-volume piston compressor pump won’t cut it with an MDF spoilboard. I think the MDF style vacuum table needs to be paired with a high volume pump, because it inherently will leak through the sides. A shop vac seems to be the minimum viable option. I’ve heard shop vac’s don’t last long when used a vacuum pumps.
Like you, I’ve worked with vac tables for many years. MDF/LDF spoilboads, with regenerative vacuum pumps. Were you using a high volume pump (like a vacuum or blower), or low volume pump (more like a piston compressor)?
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We use regenerative blowers for our machines at work, giving strong suction through the MDF spoilboards.
I am planning on using flat plastics as my materials, so I would hope that it would hold down well because of the generally smooth non-porous surface (but I really don’t know for sure). I would think the leaking through the sides of the MDF wouldn’t be an issue if I just run masking tape along the sides to block it out (that’s what we do at work as well, especially because the material we get doesn’t always lay naturally flat, but instead wavy).
I have no problem using tabs on the profile cuts as an extra way to ensure parts don’t move on the cutouts. I just want to make sure that the material will be uniformly held down to ensure nice and consistent depths across the material. Of course its also really nice not to have to use glue or double sided tape.
But now you have me a little concerned if the airweight system would pull through MDF. I definitely want a spoilboard, as I do not want to deal with onion skinning parts!
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I guess I’m not really sure why a big regenerative blower would be required, if a little piston compressor could do the job.
We used a 17hp pump on a 5x10 table. That’s 0.34hp per square foot.
Our 4x4 tables would need 5.44hp to achieve the same 0.34hp/sq.ft.
That’s what makes me think a shop vac is the right solution, as most are in that HP range.
I know the comparison is just a “quick and dirty” calculation, but still makes me wonder how you could get good suction from a little piston compressor, when the seal isn’t 100% airtight.
For years I would use packing tape to seal the material to the MDF, but masking if masking tape works, that could be a much smarter solution. The packing tape was prone to occasionally wrap around the cutter and ruin parts. Do you ever get that with masking tape?
The best idea I’ve got to date is to route the grid pattern air channels into a piece of melamine, and attach a shop vac to it. Load MDF on top.
Would love if you could keep us all updated if you go down this road. It would be sweet if it worked well.
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So, I found out on each of our 2’x4’ router tables, we use a single Fuji 1hp regenerative blower and that seems to be enough for most sheets of material that we use, provided we tape the border of the sheet to the MDF. You can definitely feel the suction when you put your palm on the MDF spoilboard.
Standard masking tape, IMO, is much easier to work with than packing tape. It sticky enough and for the most part, it stays put. We make sure to only use a minimal amount of tape around the very outside border of the sheet, to try and avoid the cutter hitting the tape, because yes, the tape would wrap around the bit if it cuts through it.
I am starting to lean towards making a table vacuum system myself, maybe using like 1/2" or 3/4" sheet of a rigid HDPE or something similar to cut the grid air channels into, and then MDF spoilboard on top. I see the Fuji 1hp regen blower can be purchased for around just under $1k, and probably a few hundred or so for a solid non-porous base to put the grids into. At that point, I’d likely opt for a 4 quadrant system, with 4 different holes and gaskets around the zones. I feel like with proper sealing all around, that the 1hp regen blower would accomodate my needs.
I’ll definitely post updates for whatever I end up going with and how it all works out!
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Do you know which model?
A 110V 1 phase blower that works with our 48x48 machine would be great. Just looked at the website, but couldnt tell exactly the right model easily.
VFC400P-5T Ring Compressor
I also like how efficient it is at 8.6amp @ 115v or 4.3amp @ 230v. You definitely want a relief valve, or you run the risk of the blower overheating.
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