[user1007]

4" er should have worked. Don't mean to insult you but you do have the depth set above the concrete right? It will bounce around on you if you do not. You need to get the final bit of material with a chisel or something.

Might need heavier tape and a finer blade though? Router, rotozip or something might work if you have clearance for it. I have a Fein multi-tool that has worked for such things so am surprised your similar functioning tool did not.

I guess you could step down to something smaller than 4" too. Something Dremel class, for example?

 

[StuartT]

The circular blade is carbide tipped, 24 tooth. SInce it is the upstroke of the teeth exiting the cut, the blade is leaving a partially splintered edge in the 12 year old laminate hardwood, and as I said, 3M blue masking tape didn't stop that. Perhaps a fine tooth conventional blade would be better.

The SoniCrafter might work okay for a short distance, but for 13' I just haven't the patience. The wood cutting blade tends to flex if you put any pressure on it sending you off the line which is always covered in dust. I am cutting into the line horizontally, not vertically, to save the teeth but you get a lot of chatter on the concrete.

And yes, the depth on the 4"er was set to clear the concrete. Kinda sparks a bunch if you don't.

 

[woodman58]

Use the 4" circle saw. Put a blade with the largest # of carbide teeth on it. Measure the distance from the blade to the edge of the saw. Get a long straight board a tape it down to the floor to use as a straight edge. Now cut the boards.

 

[StuartT]

Use the 4" circle saw. Put a blade with the largest # of carbide teeth on it. Measure the distance from the blade to the edge of the saw. Get a long straight board a tape it down to the floor to use as a straight edge. Now cut the boards.

Taping a straight guide board down with double back tape makes sense. I'll try that. Thanks.