CNC_dtl12 Sources:On the parts list its says cnc_dtl12 www.rockler.com -- --- HOLD DOWN CHANNEL. I quickly looked at their site. What exactly am I looking for?
Rockler Aluminum T-Track
McMaster-Carr T-Slotted Mounting Track
INCRA T-Track and T-Track Plus at WoodCraft.com
All of the holes on CNC_dtl01 and CNC_dtl02 are drilled through all (both sheets). What I did was cut the four 8.250" x 32.500" pieces oversize by about 1.000". I then glued the pieces together to make the two supports 1.500" thick as shown in the two drawings. When the glue was dry, I measured and cut the two supports to the proper size as shown in the plans. After cutting the end supports to size I laid out the hole locations. I then clamped both CNC_dtl01 and CNC_dtl02 pieces together making sure that they were square, flat and the hole layouts were correctly aligned. I then drilled all of the holes that were the same size completely through both assemblies at one time to make sure they were properly aligned. I then separated the two pieces and drilled the through holes that were sized differently in both pieces. It may not have been necessary but it made everything line up much better. I used the same technique for the Gantry Sides (CNC_dtl16 & CNC_dtl17). I hope the above makes sense. Make sure you measure and align the pieces more than TWICE (you know the measure twice and cut once rule) because if you don't and something isn't exactly right you ruin 4, fairly sizable, pieces of MDF!!!The on cnc_dtl01 and 02 there is some holes marked thru all, and some that aren't marked that. Does that mean that the thru all are drilled thru both sheets, and the other one just thru the top? (pages 18 and 19 in the pdf)
BTW, I used a hole saw set and spade bits to drill the larger holes and it was a total PITA. I more or less burned my way through the MDF while stalling the drill press motor repeatedly. Other people have used Forstner Bits and seemed to have better success. Just a FYI. You may want to give the Forstner Bits a try, I know if I built another one I would.
That's probably more information than you needed but I hope it helps your JGRO build go smoother. And, last but not least, WELCOME to CNCZone!!!