Squaring off homemade router table top

[dlminehart]

I'm making a router table from a couple large scraps of countertop (particle board with laminate already applied) glued together so both top and bottom are laminated. Neither of the scraps had flat sides (hand sawn with jigsaw), let alone square corners, and one scrap was a couple inches longer and an inch wider than the other.

So, I have this two-level, heavy, 1-1/2" thick, roughly 23x28, kinda rectangular thing that I need to make actually rectangular. I can see a few options.

1) Buy an expensive laminate table saw blade. Make a sled. Attach the tabletop to the sled with doublesided tape or hot melt glue. Cut, rotate, repeat. (I could use the blade on other plywood work later.)

2) With a slightly less expensive (because a little smaller) blade in my circular saw, use my saw board to guide the cuts.

3) Buy a relatively less expensive spiral upcut router bit. Use a saw board type guide.

4) See if I can find a local cabinet shop or lumber yard with a good laminate blade that I can pay to do the 4 cuts for me.

Any other options? Which would you do, and why?

[Tequila]

I'd go with the router, since it will splinter the laminate the least. The good news is that you really don't need to worry about making the edges straight, square, or smooth, since the fence (and track if you're using one) is the only thing that will guide your workpiece.

[pelligrini]

If I was doing it I would use a saw board and circular saw to straighten one edge, then use the table saw for the rest. Whichever was going to be the back edge would be cut with the CS. The zero clearance insert in my saw would lessen the likelyhood of tearout on te other cuts.

I might also use the same blade I used in the circular saw in the tablesaw if it would work. (not exactly sure if a 7 1/4 blade will get high enough)

I recently cut a similar piece of material to make into an outfeed table with an old 10" combination blade in my 21829. The neighbors remodeled their kitchen and I grabbed about anything the looked useful. The cuts did not splinter the laminate. I thought about taping it before I cut it, but it didn't seem that important for what the counter was intended for.

[cgallery]

I use my normal 40-tooth general-purpose saw blades to cut plywood with laminate on both sides all the time. Leave a nice finish, I take-off the sharp edge w/ a file.

[LCHIEN]

I'd strongly consider
1. straighten and square (to the surface) one edge of the table (the one that's already the best) on the jointer.
2. rip the opposite side on the TS to make it parallel
3. depending on the size of your table saw and or the router table top, can you then use the miter to cut the remaining 2 sides square? If not then use a guide and a circular saw to cut one side square to the two clean sides... then use the TS rip fence to cut the fourth and final side parallel. THen flip and use the table saw to clean up the CS cut side, if need be.

I would think that a sharp high tooth count blade would make adequate cuts on your laminate... it doesn't have to be beautiful? Probably want to come in with a chamfer bit or roundover bit on your router to chase the edges all the way around, anyway.

[mnmphd]

I cut down a similar sandwhich on my table saw. Staring with the
2 pieces, you need to have 1 square corner. Glue up the tops so that the
2 reference edges that meet overhangs. You don't need much 1/8" is fine.

Now using the reference edge against the fence, cut the opposite edges parallel. The using the newly cut edges against the fence cut to size.

The only issue I recall is this is fairly heavy, so you want some infeed and outfeed supports.

Using a router does have the advantage of keping the heavy peice stationary,
though it requires a long bit or multiple passes. To keep all the edges square and parallel, I would make a thin full size pattern on the table saw to follow
with a edge trimming bit. A bit with the bearing may be easier since you can
work you r way down the thickness. You could also cut one piece, then glue it to the second, and use the first as reference foe the trim bit. In any case where I would use the router, I would rough cut to approximately size to minimize the material the router has to remove.

[LarryG]

Any of these methods will work, and I concur that there's no need for a new and expensive blade if you have a decent combination blade that's nice and sharp.

I will voice a rare disagreement with Loring, however, in that I would not square the first edge on the jointer -- an inch-and-a-half of particleboard will not be kind to your knives.

FWIW if I were doing this myself, I'd use your Option 1, with or without the laminate blade. Reason? It's fast, simple, and the results will be plenty good enough. The "sled" can be nothing more than a suitably-sized piece of plywood with at least one good edge to run against the table saw's fence to fair the first edge. If I had concerns about chip-out on that first pass, when the top assembly is clear of the throat plate by the thickness of the "sled," I'd make a second clean-up pass on that side after fairing the remaining three edges.

[LCHIEN]

...

I will voice a rare disagreement with Loring, however, in that I would not square the first edge on the jointer -- an inch-and-a-half of particleboard will not be kind to your knives.

...

you probably have a good point there.