Trunnion Jig

The files for this are on thingiverse at Parallel Test Jig

In my continuing quest to improve my table saw with 3D printing, I made this jig to attach to a Microjig ZEROPLAY miter bar. (A hell of a lot of leftover plastic cruft from injection molding needed sanding off the side and top before this was in shape to use, but it is OK once you fix that problem.)

Here it is on the printer. A big print, but not quite as big as the push stick. I printed the clamp for the dial indicator on the solidoodle and used super glue to join the two pieces.

Here you can see how it fits on the saw to measure distance to the blade (should also be able to measure the fence distance with the fence close enough and the blade dropped out of the way):

Now for the critical question: Just how bad is the trunnion alignment on this ancient Craftsman 113 table saw? Here is the dial reading at the far edge of the blade:

And here is the reading at the near edge of the blade (rotating the blade around to the same mark to measure same point on blade):

YIKES! Looks like I'm destined to spend time rooting around to try and find the right bolts to loosen and right places to smack with a mallet to try and get the blade more parallel to the miter slots (not sure I could make it worse :-). A dirty sweaty job I probably won't tackle any time soon.

NOTE: Page 30 in the pdf manual shows the procedure, and it looks like great fun. For one thing, need to tilt the blade up to 45 degrees in order to get to one of the bolts that needs to be loosened (but then need it back at 90 degrees to test if it is aligned properly - what fun).

The continuing saga of the table saw improvements can be found here.