lock miter bit

[Brian Runau]

any advice on setting up and running lock miter bit?

Thanks.

Brian

[Chris Harry]

Whiteside has a great"how to" with their bit on their website: http://www.whitesiderouterbits.com/LockMiterInstructions.pdf

It should work about the same for any other brand bit

The best advice Ive seen to set it up is to run 2 separate panels both in horizontal mode. Flip one of the boards over and then mate it up with the joint of the other board. When properly setup, the two boards will join perfectly flush.

Another tip is to "burnish" the joint with the shaft of a screwdriver. The bit will create really sharp miters, which may or may not be what you are looking for. I actually purposely set mine up "wrong" when making a post sleeve with PVC trimboard. The trimboard edges were slightly rounded, so I was able to keep the "roundness" of the edge and prevent a sharp corner that would actually cut your fingers.

[John M. Cioffi]

Brian,
I have an article my friend produced, but it is too large to upload here. I'll try to send it via your e-mail.
John

[Brian Runau]

Thanks, much appreciated.

Brian

[David Epperson]

Nice set up tips Chris. I've been trying to learn how to use mine. The flat cut's come out great, the fence cuts I get a lot of end grain breakout.
Right or wrong I've started working the bit in taking multiple light passes until I get all the way against the fence. But my set up is a bit home made, so I have a fence that is only just a bit taller than the cutter and a jig that rides on top, so it's pretty easy and safe to take as many passes as I need to get to full depth. I still get some break out, but not so often now.

[Jim Kirkpatrick]

I ran through the setup on my lock mitered drawer tutorial (http://sawmillcreek.org/showthread.php?t=132180&highlight=lock+mitered)

[Jerome Hanby]

The setup on woodshopdemos that uses the playing cards looks like a winner. That's what I'm about to try. I even found the height gauge he uses for cheap on Amazon. If you don't have a way to make micro adjustments on your router height and router table fence, I'd pick a different joint. Trying to get the correct settings with my Hitachi (turn the router motor in the base to adjust height) router was driving me to drink. I bought the Freud combo table, fence, and router from Woodcraft and it's got the precision I was lacking...

[Jerome Hanby]

Nice set up tips Chris. I've been trying to learn how to use mine. The flat cut's come out great, the fence cuts I get a lot of end grain breakout.

I was getting excessive tear out too. I'm thinking my Woodcraft store brand lock miter bit (and my endless tinkering cut after cut trying to get it set correctly) may be a big part of that problem. I bought a new Freud Quadra bit (four cutting surfaces instead of two) and I'm hoping that will help. Of course I have to re-work all my settings for the new bit...