Q: Best type of Flush Trim bit?

[mttt]

I had been using a standard 2-flute flush trim bit for some template routing. Cut quality had been pretty good - but this weekend I had one experience with terrible tear-out that ruined the piece. A bit like this:

think I recall seeing The Wood Works Guy (David Marks) use a spiral flush trim bit (like . But memory fails me.

Wondering, in general, will I get a higher quality cut (less prone to tear out) by switching to a spiral flush trim bit? I'm willing to invest the extra bucks if the payoff comes back in cut quality.

[Tom]

Where was your tear-out? If it was on a cross-grain cut, you should have better luck with a spiral. Or back up your workpiece with a piece of scrap. But a spiral can tear out (albeit minimally), along the top or bottom depending upon it's type (i.e. upcut or downcut). Tom >Subject: Q: Best type of Flush Trim bit?

Someday, it'll all be over....

[David Chamberlain]

I have had good luck with a 3 bit system. I use a 1/2 spiral milling machine cutter (either 2 flute or 4 flute) with a template guide bushing. That does away with most of the waste and leaves only a small amount to remove. I then have a flush cut bit and a pattern bit. I pay close attention to the grain direction and flip my work and template over so that I are always routing with the grain. That avoids most of the big tearout problems. I also pay attention to the grain direction when I am doing the initial routing because it is easy to rip out a big hunk of material if you go the wrong way against the grain.

[Routerman P. Warner]

Might be that stage cutting would have cut down on the tearout. Have seen serious tearout with every type of flute design. More on templet cutters and stage cutting at the

link.

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[Dan Valleskey]

I found a 3-fluted flush trim bit, I really like it. slightly less tear out. Damned if I can remember what the brand name was- sorry.

-Dan V.