Lock Miter Router Bits
2 flute, carbide tipped. To join materials at 90° by cutting a 45° miter and a perfect matching tongue & groove glue joint. This joint not only increases mechanical strength, but also increases glue surface area and automatically aligns parts. Set-up blocks sold separately below.
Lock Miter Instructions (PDF)
|Lock Miter Router Bits|
|#5547||3/8 to 1/2"||1-3/8"||1/4"||#9750||$29.95|
|#5548||1/2 to 3/4"||2"||1/4"||#9751||$37.50|
|#7847||3/8 to 1/2"||1-3/8"||1/2"||#9750||$36.50|
|#7849||1/2 to 3/4"||2"||1/2"||#9751||$38.50|
|#7850||1/2 to 1-1/8"||2-3/4"||1/2"||#9753||$47.50|
Set-Up blocks sold separately below.
all customer reviews and ratings
Average Customer Rating: (5 reviews)
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By tom siegel (Charlevoix MI US)
Test cut in 12" long dry oak was absolutely perfect. Found the set up guide blocks useful.
Lept to a 7 foot long cut in walnut for box beams for a king size bed. Absolutely loved an earlier review suggesting leaving 1/16th or so in thickness when milling your own stock. I used a drum sander to remove the excess after the miter .. avoided risk of snipe on the planer .. got a knife edge.
Had early problem with glue-up. The tongue and groove, when using a single bit and single fence setting, are apparently so tight, there is little to no room for glue squeeze out .. especially in a 7 foot long joint.
Resorted to gluing only the 45 degree flat surfaces, leaving the tongue and grooves dry. Much better fit. Got the minimum desired squeeze out at the 90 degree inside and outside edges making for a very tight looking edge.
In my project, with the box frame still in three sides, I glued in some ribs to make up for any loss of strength I caused by not gluing the tongues and grooves.
By Ken Rupkalvis (San Antonio TX US)
I used this bit to make many drawer boxes for a very large desk. It's rock solid after glue up and very square off the router. I found the setup block helpful in that it cut setup time significantly.
By John McCormick (Spring Te US)
I too used this bit to make table legs because I did not want to show a glue joint down the piece. I was very happy with the outcome. The setup block was nice but not 100% necessary.
Also, if you are milling your own wood to thickness, I recommend that you leave a sixteenth or so on the thickness before routing the lock miter. This way, you are not producing a sharp edge to ride on the out feed fence. Mill to final thickness after the miter has been routed.
Best of all, the joint produces a near perfect 90 degree joint with little effort. Just make sure to clamp it tight.
By Paul Smith (Altoona PA US)
If you want to build a table leg made from 4 pieces of wood this is the answer. Used it to make legs for a Craftsman design dining room table. Many of my woodworking pals thought the legs were solid, but I explained how this bit works and a couple added this bit to their collections. Also, this is a great bit for making drawer boxes. The front, sides and back interlock and make a joint of unprecedented strength. Also, the set-up block is a near necessity for accurate joints. There are alternative set-ups but the block is easiest.
By Paul J Schneider (Red Lodge MT US)
I have used this product and found it to be very useful, and would recommend it to anyone wanting a secure joint in their woodworking. The video is most helpful.