Here's the best price anywhere for t-track. Order over $100 worth and shipping is free. You'll need more than $100 worth. https://www.orangealuminum.com/t-tra...es-oa7150.html''
Most folks trust screws to hold the t-track. However, some, including me, don't trust screws when we don't have to. Lay out t-track on your torsion box. Cut strips of 1/2" MDF to go between the t-track. Glue or glue & screw the MDF in place. I use only glue. Finally, top with 3/4" MDF cut to overlap the edges of the t-track, but leaving the full width of the t-track slot open. Glue or glue & screw the 3/4" MDF in place. I use only glue. An alternative for the top is fastening the full sheet of MDF and use the CNC to cut out the slots. It's hard to get the glue spread on a 4'x4' piece of MDF and clamped in place before the glue sets too much, though.
Descriptions are not nearly as good as photo and videos. Here's very good video showing what it looks like and explaining it:
A nice thing about Peter's technique is you don't need screws at all. I use a few to keep the t-track from sliding back and forth, but I don't need them.
There are a lot of good tips and tricks on Peter's YouTube Channel. Give it a look see.
I depart from Peter when it comes to spacing the t-tracks. If I recall correctly, he has them 7" or so apart. I tried that spacing and bitterly regretted it. Seemed like the spacing was wrong for what I was cutting - time after time, after time, after time . . . . I have all sorts of wood hold downs, some way longer than they should be. I'm just finishing up my 2nd build. I'm spacing my t-track 4" OC.
Attached is Peter Passuello's video, Don't Spoil Your Spoilboard. I use the technique. Works like a charm, but IMO, it works best with a touch plate of some sort. I have Bill Griggs' Maker's Guide. There are similar plate on EBay that are less expensive. Or, you can try cutting your own. It is vitally important that you set the the offset for the plate's thickness EXACTLY. Any error, however slight, will leave you cutting too deeply, or not deeply enough.
I think I've about covered it. Let me know, if I failed to address a question.
If you have some time to kill, you might want to take a look at my build thread. There may be some discussion about spoilboards in it, although I haven't yet installed mine. I have an order for more t-track coming from Orange Aluminum.
https://www.cnczone.com/forums/diy-c...machinist.html
Gary