ply tearout

[Sean Hughes]

I purchased some sanded plywood at the local HD. I'm building some shop cabinets and during crosscutting and makings rabbits, I've experienced tearout. The top veneer seems very thin to me. I was curious if the tearout is due to the plywood or my blades? Would Birch ply have the same problems?

Sean

[Hank Walczak]

Sean - Best way I know on ply is to make a scoring cut with a knife first. Works very well. Even with zero clearance insert you'd still get some without scoring first.

[Jim Dunn]

I've found that the plywood from HD and blue box has minimal veneer thickness. This isn't true with better cabinet grade plywood.

That said, I agree with Hank, score the line before you make the saw cuts. Another way is to take a scoring cut with the saw blade (just deep enough to cut the veneer) then raise the blade and finish the cut.

[Steve Cox]

If you crosscut the ply you will get tearout. You shouldn't get it while ripping. If you get tearout while ripping, check your blade. To minimize tearout while crosscuting, I find it useful to use a zero clearance insert and to score the panel first. Set the sawblade about 1/16" of an inch above the table and run the panel over the blade, then raise the blade to a cutting height and make your final cut. If you're making multiples it is helpful to set the blade at the 1/16" height and then to count the number of turns to retract the blade and to get it to final cutting height. I get tendinitis turning the crank that many times but it works.

[Ted Shrader]

Sean -

The other guy's suggestions about scoring with a knife or the blade are good if the saw is in good alignment. Be sure to use a ZCI.

Have you checked to make sure everything is in alignment - blade, fence, miter gauge or cutoff sled, etc. How many teeth on the blade? Are you trying to get by with <60? Is the blade sharp?

Good luck,
Ted

[Mark Singer]

The good face should be up... the blade should be a plywood blade or a WWII with min set at least 40 teeth...I use a blade with 80 teeth and don't have to score. It might be bad plywood.

[Gord Graff]

It might be bad plywood................Mark Singer.

Hello Sean,

It's not uncommon to get lousy plywood from the big box stores, I sent a lift back last year to Home Depot. They tried to tell me that it had more to do with operator error (me and the saw blade) than the plywood, I simply brought a sample of freshly cut good stuff and a sample of the plywood they had sold me..................they took back the lift.

All the best
Gord