table saw blade dilema....

[Mark Rios]

I'm trying to cut a 1/8" groove for a spline on the ends of a cutting board to give extra strength for holding on an end piece. While making the practice and adjustment cuts i noticed that the groove did not have a square bottom.....it had tiny chamfers at the corners. I have two good blades and other misc. blades. They are Freud Glue Line Rip, model LM74R010, 30 tooth with 12° hook and a toothe design that says, "TCG". The other Freud blade is the LU82M010. It says that it has the same tooth design.

It looks like the teeth alternate between the squared off teeth and the chamfered teeth. Shouldn't the square teeth give me the cut in the corners of the groove? What other type of blade/tooth design do I need to cut a square groove?


As always, thanks to all of you who help and give advice to those of us who are woodworkingly challenged.

[Jim Becker]

About the only blade that will give you a "true" flat bottom would be a dedicated ripping blade with flat profile teeth, but you'll want to be sure to use backer blocks at the beginning and end of the cut to avoid tearout. The reason you're seeing those little tails with the other blades is that the teeth on your particular blades must have a high angle profile on some teeth that is ever-so-slightly longer than any rakers or other teeth. This is done to insure that there is a slicing action at the very edge of the cut to keep it clean and normally a feature of a combo or GP blade. (Your dado set will do this, too...) BTW, there are too many "ripping blades" that for some reason also have a modified tooth profile--I guess they figure some folks will leave it on the saw for other types of cuts. I have a TK Freud from my previous saw that is like that. My regular ripping blade has 100% flat profile teeth.

[Mark Singer]

You can run it through the router and it will be square. Use a straight bit or an upcut spiral

[Mark Rios]

ok.....! Once again you folks are awesome....just the answer i was looking for.straight, to the point and very informing...thatnks very much ...