Nah- i pulled it from up thread.
Was just alerting Aaron to it
Whoops. 
Today I planed the MDF (my CNC has nearly a mm height difference top and bottom. Some day I am going to fix that) and I though: Hey, I am not cutting deep, only a mm max, letâs give it some speed, so I cranked up the max to 8000mm/min. Should have also somehow reduced inertia as well and not leave it at 85⌠For the planing it was fine, but the other try after that was reaaaaly weird because the whole table shudders when it goes from 0 to 8000 in 2mm⌠The table holds the MDF well, the stock not that much. I cut out two small things, one worked without tabs, the other would have needed tabs still. Need some time to optimize performance. I am definitely getting rid of the insulation again, that reduces airflow at the edges a lot more than it helps.
See here:
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First real test: Cut some 4mm plywood, a little too deep, but still worked. What I noticed is that I definitely need tabs, at least at the corner pieces (the rocket on the bottom left was done without tabs and moves immediately after cutting. Will have to try further whether tabs are needed everywhere, but I guess so. Nevertheless I count this as a success. 
You can also see that there is still a lot of free space that I did not cover, the whole right side and the two rockets that were cut prior, so at least 1/4 of the whole area wasnât covered at all.
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First bigger project, 12 rockets. As soon as the last one was cut out it wasnât held down any more and could be moved by hand. Might have to add some double sided tape to the corners. I consider this to be surperior to screwing that there is no possibility to run into a screw or clamp, downsides being that it does not seem to hold down stuff well enough if you cut through. I also fear that it might not work well with smaller parts, but havenât tested that yet.
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Update: You absolutely MUST plane down both sides of the MDF for air to pass through unrestricted. I only did it with one side before, even when doing the rockets and the holding power is a lot less. Like, shockingly less. I made a short video where I can push a piece of wood easily around the spaces that have not been planed and as soon as it hits the planed down piece, it is stuck. Really interesting. I suppose I could go with the 18mm thick MDF after all if I planed down the other side as well. Will try that later, also ordered 5mm MDF.
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I am going to blow your mind even more: It does not have to be thin, since the air canât go anywhere anyway:
18mm MDF, only one side planed yet. Plywood boarder to stop the air from escaping.
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