Going to Build

Some details of the Indexer

Here are some details of the indexer I designed. First, the clamps that hold the index bar to the rail are made from 0.75" UHMW. The translucent area in the drawings below are the UHMW. It is in two pieces, the main body and the clamp head. the clamp head has a "V" shaped protrusion that fits into the "V" grove in the side of the guide ridge. It is held in place by the Clamp Knob and Stud. The main body is attached to the index bar with the Attachment Bolt and Knob. There is a small open area between the main body and the clamp head below the Clamp Knob Stud, this allows the clamp head to be tightened against the guide ridge.The index bar is made of 0.375" UHMW and can have two sets of index holes. You simply remove the bar from the clamps, turn it over and reattach. It has been suggested that a strip of pegboard could be used for the bar. I havent tried it yet, but I cannot see why it would not work.

The index pin module is also made of 0.75" UHMW, and has an aluminum Top Plate that traps the pin and spring. The index pin is a 0.25" hex bolt that has had the head cut off and the end rounded over some. The bottom nut on the pin gives something for the spring to push against, the top nut is just to lock the knob in place. The body of the assembly is attached to the SRK with two screws. It sits over the index bar and straddles the guide ridge (for no real reason).

Alignment of the rail to the center line of the holes to be drilled is accomplished by means of an alignment jig made from an SRK and a section of aluminum angle. First you set the rail with the router bit centered on the center line. I use a brass setup bit that has conical points on each end and a 0.25" and 0.5" shaft (one half each). This sets the distance. then I adjust the alignment guide so the edge of the aluminum angle is on the center line. I then set one end of the rail the proper distance from the line with the alignment guide and loosely clamp that end of the rail to the work piece. Slide the alignment guide to the other end of the center line, adjust and clamp that end of the rail. Go back to the other end and reset if necessary.


I hope that this has answered some of the questions that you might have about the jig. If not dont hesitate to ask.