Hey Gaetano, hey @JimHatch, hey @Mitch, hey all,
I already had the thought that I should have better also provided a link to Woodworker QCW Frame (Secure from Above) in my post – here it is
By the way the corresponding wasteboard dimensions file (PDF) for Woodworker model is here (as always, dimensions provided only in imperial units )
The difference between the two QCW versions is that the “Secure from beneath” version has only screw holes in the aluminium extrusion profiles, whereas the “Secure from above” version has what Onefinity calls “PEMS” but are in fact Swage Nuts that are shown here on QCW frame.
I also wanted to have the “secure from above” version, but since before ordering I was not sure whether possibly imperial threads were used (not common outside the U.S., so definetely not wanted), I ordered the “secure from below” version and got me a bunch of “Setzmuttern M5”, so that I can install the swage nuts myself and be sure of the thread used.
Note that in case you don’t make the MDF wasteboard slats with a g-code program run on the machine, but by hand as shown in the manual or in the video, you will notice that for the 9.5 mm / 3/8″ deep holes for the screw heads, they use a forstner bit and as depth stop they suggest marking the depth with tape on the drill bit, however for acceptable depth accuracy and repeatability I would suggest better using these nice and ingenious Star-M Depth stops :
The plastic cap rotates freely and stops rotating when you reach desired depth.
I use a set of them, from 3 mm (=approx. 1/8″) drill diameter upwards. Picture shows ⌀ 15 mm drill (=approx 19/32″). Available here or here