Binding Cutting Fixture. This binding fixture is designed to use two different types of cutters: the set of router bits from LMI and Stew Mac or just two simple one-half inch straight cutting bits. I won't bother with the Luthier cutter set as that will have its own instructions with the set that you purchase. I will explain the use with a standard straight cutter bit. Once the cutting depth and width is established the two cutters will work the same.

The mounting unit has two plates. The front two-inch square plate is slotted and used with bearing piloted bits. This is removed for the pilot fixture that is shown in the pictures. Two screws that come with the unit for the piloting fixture are set into the threaded holes. These will hold the pilot fixture and the trimmer. A certain amount of 'float' is normal. These things totaly eliminate the need for the expensive router sets but do take time to set up properly. The trimmer that comes with my unit includeds the piloting fixture. Note: you may order other fixtures from the owners manual.

It has a micrometer like adjustment. You can set the width of cut with this and the depth of cut with the adjustable locking collar or take the pilot arm off and use the luthier combo bits if you want. It is very easy to switch back and forth. The carriage holds the guitar body. You adjust the outside L brackets to hold the body and adjust the lifters to make the body flat. I use a twelve-inch scale and try to keep the body to within one-quarter-inch. Then I clamp the router fixture to a firm table and work the body around it counter clockwise. Try to keep the working area to the front of the cutter. Cut the outer binding first, then the top. If you think you may have a problem with tearout, afix a little masking tape, make the pass in that area, then remove the tape and make the final pass. Sometimes spruce will pull apart at the area of the lowerbout The trimmer adjusts for depth of cut by lowering the bit into the work. Most trimmers are very similar. Always check the adjustments with a scrap to be sure you have the correct settings.

The width of cut is adjusted by the little pilot fixture. There is less tearout if the perfling is cut before the side binding. The direction of feed is important also. With the cutter spinning in a clockwise rotation, feed into the cutter, and rotate the body counterclockwise. After you do a few you will develop a good feel for what you are doing. Always wear safety equipment and watch what you are doing. If you feel the trimmer binding, you may have the body set too high. Watch for bending springs. In the new versions of the fixture the springs have been removed. While they were on the original design by Tom Ribbeke, this design uses the weight of the trimmer to do the work.

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