Sanding Shooting Board with Vernier Scale

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This is a sanding shooting board with a Vernier scale, allowing a resolution down to 0.1 degree (or 6 arcminutes). This was designed for 1/4" or less balsa and basswood modeling wood but it can definitely accommodate a wider variety of materials and sizes. With small modeling wood, even the sharpest razors can deflect or slightly crush the wood and being 1 degree off is noticeable at this scale. This provides a means of achieving extremely clean and square miters. While 0.1 degree resolution isn't often needed, it helps to know if you are erring over or under your desired angle. The miter gauge can rotate ~68 degrees. Common angles are marked on the baseboard. This is designed to function with the sanding block included but should be able to work with simpler sanding blocks and probably small block planes. A 45 degree block model is also included that will allow compound angles. Blocks with other angles can easily be modeled and printed if needed. It should be noted that the complementary angle to the one shown on the gauge can be mitered by placing the material against the other face of the miter gauge. The shooting board is designed to use two #6 screws (3/4 in. and 1 in.) and three locknuts. Two locknuts fit into the bottom of the base while a third is goes into the knob. The one that goes into the knob should first be screwed all the way up the 1 in. screw (some loctite/CA glue helps but isn't needed) before being pushed through the knob. The screw in the knob is useful for pulling through the other two locknuts as it is a very close fit. The bushing is asymmetric and will [should] only work one way. It is designed to be a tight fit and some light sanding may be needed. Given the low tolerance design, some sanding is expected to be needed to get the gauge to read at 0 degrees (technically 90 deg since it's square), otherwise it may be off by a few tenths. This was intentional, that way the extreme position can be dialed in to be square, rather than have an undersize part and overshoot. The expectation that one will have sandpaper is reasonable as that will be needed for the block. The setback of the sanding block face is designed for one layer of Xfasten Double-Sided Carpet Tape and a 4.5" x 1" piece of 3M Cubitron II sandpaper. I'm sure most adhesive backed sandpapers will be fine. If the sandpaper is a bit proud of the block face, it will wear the top running edge a bit but that will not hurt the functionality of the shooting board. I used 120 and 220 paper. Before assembly, it is useful to sand down any sign of elephants foot on the miter gauge. Bushing_V2 is up. It extends the lobe by one more degree so it runs a bit truer and more effectively reduces gauge slip while tightening the knob.