Originally Posted by
andrew whicker
It's obviously easier to cut parallel straight cuts w/ the tracksaw. So cut the parallels first then use your square to ensure it's square from both sides for your cross cut. When you have 3 sides cut, you can use the X measurement method to check square and mark the 4th cut via that method. If the measurements don't make sense, you can re-cut your 3rd cut (your cross cut) accordingly.
I made a pretty sweet wet bar with +/- 1/16" accuracy on my panels (using tracksaw cuts and table saw cuts when I could) so I'm not totally sure what the problem is with 1/16" accuracy on a side panel. Heck, I'm sure that one of the panels was even an 1/8" off... I agree the correct method is sub'ing out / owning a large CNC and I do remember the assembly / glue up wasn't as fun as could have been w/ zero precision problems, but I did get it done and everything assembled pretty well at the end.
One thing I learned w/ those tracks is that the sacrificial cut line can be off pretty easily (by 1/32 or 1/16). They seem to get torn at times vs cut cleanly. The real surface you are using for reference is that dado on the track (as you know). So when extending my track with two tracks, I use my 60" straight edge against the dado to ensure they are straight vs butting them together cleanly (and assuming the track manufacturer made perfect 90 deg cuts). I like the idea of having that quick tool that references the dado to mark the cut line. I'll have to make one of those. That would definitely reduce error.
As the person above said, I also double check the measurement to back of the track.