So have some smaller pieces of stock that I need to clamp down for cutting. Any suggestions on method? I know Chris has been using a piece of MDF with some T-slots built into it, but I hate to build a fixture for one project.
I probably don’t have your answer, but define smaller for those that will.
7" x 18" x 3/4" or so. Currently moves under bit.
Screw it down to a bigger piece of mdf, but down’t screw it into the spoil board. Use something else to screw it down to and then use vacuum hold down to hold both pieces in place.
Thanks,
Alyssa
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Get a good non-skid mat between work piece and bed. There is some webbing material around the workshop that might work, otherwise maybe stop by Walmart or Hobby Lobby?
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Building fixtures is just kind of part of things when it comes to CNC working. In most cases fixtures are half the job. I wonder if you could design a modular fixture that would allow for using smaller stock on the cnc table. That way you wouldn’t just solve the issue for yourself but also for the other members that follow you.
Another option is to spray adhesive your work piece to the table. This would give extra hold beyond the vacuum. After your done, just sand the glue off. Also based on residue you might have to resurface the sacrificial top.
make sure to clean the area before you stick it down, the dust could make the adhesive useless.
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This seems large enough that you might be able to get by with cutting a pocket to fit your workpiece in a larger sheet of cheap 1/4 plywood or panneling, so that it provides the lateral stabilization.
I fixed that for you.
I find that I often spend 2X as much time building a fixture or tool than I spend using it. But that the total time of fixture and work is still far less than if I went forward without the custom tooling or fixtures.
This is what I and others have done. Definitely run it in preview mode and pause as appropriate to make sure you won’t be hitting screws 
You know, I wonder if I’m overcomplicating. Perhaps if I sandwiched the piece between two larger pieces of MDF on both sides, whether it would, between the vacuum and the friction of the MDF edge, hold the piece pretty firmly using vacuum alone. I’ve got some 1ft x 4ft pices of MDF I’ve used for test cuts, they hold down very firmly, and are pretty square on the edges. That should lock down the X,Y axis, and I don’t think the Z axis is much worry.
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Overcomplicating is relative 
I used an EXTREME option once. Our only piece of sacrificial board was once very warped (and extremely gouged and unable to resurface due to warping). I had several people wanting to test, so I took some drastic measures. I basically covered the entire table and used tape to cover holes that I missed. I had our 5’x10’ table reduced to about 4’x14". Pretty sure in this state it would hold pieces for Nicole’s 10"x10" art show without problems
PS: Notice the tape on the front face of the machine above the word “Classic”. There are holes in the plastic there. It would seem someone rested a piece of wood against it and drilled it. Please don’t be an idiot…
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Brian,
You know, I wonder if I’m overcomplicating.
We ALL learn when members ask process questions like this - it was well worth hearing you out and others on this.
JAG “The More You Know, The More You Realize You Don’t Know…” MAN
Did it really improve the vacuum that much?
It did increase the vacuum, but it’s probably not worth all the effort involved. I pretty much had nothing to lose at the time since we didn’t really have a working spoil board
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I think when working the edge of the vacuum’s capability, everything you can do may help. Alex was talking about finding some LDF which, according to Multicam, makes a much better spoilboard and improves suction on the table a good bit.
In fact, he got some. The LDF is on the machine now.
And sadly it now has some aluminum chips embedded in it.
I flipped it back over after looking at it (so it shouldn’t affect anything), but yeah 
PS: Don’t let the L in “LDF” fool you. A 5’x10’ sheet of it is a two man job when flipping or moving it 
The dent on the side of the spoil board is evidence the aluminum cutter figured that out too late.
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SAY WHAT?
You can also use double-sided tape (the heavy duty type), or there is a 3M product that serves as double-sided tape but detaches when you pull on one end and stretch it. You need to attach your workpiece to your own sacrificial board which you vacuum to the table’s sacrificial board. Don’t use MDF - it has a waxy surface that is not suitable for double-sided tape. The tape will prevent the workpiece from moving laterally, but you can break it away from the sacrificial board by leveraging it upwards.