Summary

This is a replacement for the blade height adjustment worm screw on a Hitachi C10FL table saw. The worm screw part no is 726713.

You can buy this from Hitachi as a replacement part, and probably should. However I needed my saw back in service immediately, so this is an emergency replacement.

Instructions

I printed mine in PLA at 100% infill on a Makerbot Replicator, using both raft and support on MakerWare. Cleaning the support material from the threads is a bit tedious. I did not find it possible to get particularly smooth gear faces because of the support remnants, but that has not been a problem.

I've made a couple of minor adjustments to the design after printing and installing the part - the shaft hole was too snug, and the overall part was slightly too long. I was able to fit it, but have tweaked these files based on that experience. You may need to refine those dimensions further.

The action of the printed part is very smooth, certainly feels as good as the original, and is holding up fine under use so far.

This worm screw takes a fairly heavy load, so I have no idea how long this part will last. If it were to break while the saw is cutting there is a chance that the lift imparted by the blade on whatever you are cutting could cause the blade to rise, so use at your own risk. In my own experience, when the original broke, the blade dropped down into the table.

The thread STL was separately generated using the attached python scripts and imported into the openscad file. My initial attempt to produce the thread entirely using CSG in openscad resulted in unusably slow generation time.

The hexagonal recess in the bottom end (not visible in the photos) does NOT appear to serve a purpose as far as I can tell. I copied it from the original, and assumed there was some sort of nut that needed to be recessed into it, but upon reassembly I found that end sits against a flat collar. If I print again I will remove it by commenting out the reference to nutRecess at the end of wormscrew.scad.

Wormscrew for Hitachi C10FL Table Saw Blade Height Adjustment