I'm searching for an efficient, low-tech (non-CNC) method for squaring panels. Efficient is the key word here. My experience with sliding-table saws has been less than encouraging. (Have used Griggio and Laguna.) Small shop verticals are okay for rough cuts but not good enough. I was spoiled by a big Streibig a few years back. Maybe some kind of manual router based machine or jig that I'm not familiar with would be okay. Right now I am using a hand held circular saw with a straightedge and square and fine tuning with a router with a pattern bit and a straightedge. It works, but it's slow and temperamental. Panels narrower than 16" I do on the tablesaw with a shop made cut-off jig and am happy with that, but wider stock is the problem.
(From WOODWEB's Cabinetmaking Forum)
Use a *good* sliding table saw (Altendorf), and set it up correctly.
Make a sled from 1/4" thick plywood that has a good core and is as flat as you can find - about 30" x 48" for a Powermatic 66. You will need a side extension on your outfeed table to support most of the sled. Leave about 12" or so of space between the saw table and this side extension so you can clamp stops to the sled when you want. Use hard maple or white oak for the guide runner in the saw-table slot. Mill the width dimension so the strip slides with barely detectable deflection. Surface both sides of the plate with vertical grade plastic laminate. One piece on top and two pieces on the bottom. The two bottom pieces of laminate are butted to the guide strip and form a shallow groove to position replacement guide strips when they wear out in a few years.
Use #8 FH screws to attach the guide strip and the backstop (hardwood, 48" long x 5/8" thick x ~1 1/2" wide) to the rear edge of the laminated sled plate. Use plenty of screws - spaced about 3" apart is good. The backstop positioning is where the magic happens. When it's tweaked to an exact 90 degrees, panels up to 27" wide can be squared with ease. The whole deal weighs only a few pounds, so you can flip it on and off the saw one-handed and lean up against something handy so it's fast to use. I set up a slick-surfaced outrigger and use the sled to square up refrigerator panels and particleboard substrate for countertops. Cotter-pin simple, cheap, fast to use, accurate, long-lasting - what more could one want?
There may be other aftermarket sliding fences out there, but this one has a well-established reputation for customer satisfaction, which is not to say that everyone who has ever used one is satisfied, but that the Excalibur is working well for many shops, including mine, and has received more positive reviews than any other I'm aware of.
What I particularly like about the Excalibur is (first) the table and rails run on roller bearings that are easily adjusted to take out slop, and the table's ability to stay in tune. Second, the fence is very high quality machined aluminum, quick and easy to remove and replace when required, without losing its crosscut accuracy. Finally, the fence is very easy to micro adjust (square to the blade) with a locked threaded bolt, any time you want to tweak it for dead crosscut accuracy.
Other features I like are the high quality, simple to move, adjustable stops. I have two on my fence and find the second one very handy for the times I need to interrupt my first cut length setting, during a run of parts - I simply flip up the first stop (out of the way) and use the second stop for the odd length cut. After making that cut, I can return to the first stop and know that the length will be dead on with the remainder of the parts, since I didn't have to move the first stop.
The standard sliding stop on the fence will allow up to about 65" to the left of the saw blade (depends on how far you place the right end of the fence away from your saw blade). There is a built-in, sliding fence extension on the left end of the fence that slides out and can be locked in placed for longer lengths, up to full 8' length of standard sheet material.
You can locate the fence behind the panel, (as I do for 99.9% of my work) which will allow stock up to 36" to be crosscut, or you can locate the fence ahead of the panel for full 48" crosscuts - which I rarely do - but it's possible with the Excalibur with a minimum of fuss. Miter cuts are very easy to set up with the fence and graduated miter rail along the left side of the table, and returning to square is very fast and accurate because of the stop screw built into the system.
Only drawback: It takes up a lot of floor space, but I don't see how to make it less. If you have the room, I believe you will be satisfied with the Excalibur sliding fence, at least until you get that Altendorf :-)
The initial (full day) tune up included removing some parts from my existing PM66, cutting a short section off the left end of my Beistmyer fence rail, drilling and tapping a few new holes to accept the Excalibur package, and then aligning the Excalibur rails, adjusting the bearings, adjusting the leg levelers to bring the top of the Excalibur sliding table close to parallel to the top of the PM saw table, and a few other adjustments necessary to tweak the top of the sliding fence to dead flat and parallel to the top of the saw table. All of this can be accurately done with a tape measure, a 48 level, and some careful attention to detail, which takes time took me a day, but a day worth the effort.
Comment from contributor A:
I use the pattern cutting way. Cut a giant contactors square out of a factory edge of a sheet of plywood. Sscrew it to your piece. Then attach a board to your fence. I use a 5" board with 2 1" holes drilled in it. Use f clamps to attach it to the fence. Put the board above the blade flush with the outside high enough to clear the piece you're trying to cut, but low enough for the plywood pattern to ride against it. I just made a 5'x5' coffee table. It worked great.