Shopsmith Forums

This is from the horses mouth. In Scott Markwood's second interview video with Jim McCann he talks about SS alignment. He said every SS is aligned at the factory. The table miter slot is aligned to the blade to 0.010" over 10 inches. They use a 10" square flat plate not a saw blade. The fence is aligned to 0.010" over the length of the fence.

Another interesting thing he talked about was the testing procedure he developed when designing the anti kick back pawls in the upper saw guard.

I encourage everyone to watch the entire interview. Very interesting insight into various subjects at Shopsmith.

John,

I just finished watching it and I agree it is a must watch for Shopsmith users. If anyone missed it watch the first video too.

I usually aim for better alignment than that --usually .003 or less. But of course I'm using a blade.

I got to tour the factory with Jim earlier this week and the fixture that they now use to align the tabletop is super-clever. It is done as they attached the tiebar assembly to the table, prior to the table even being mounted on a Mark 7. You and I would mount a blade or sanding disc or alignment plate on the headstock, but they don't even need to bother with that thanks to a fixture that Jim developed. Likewise, the rip fence is assembled and calibrated on a fixture that features a sliding dial indicator. I really wanted to snap pictures, but understandably it wasn't allowed. Jim did allow me to snap a pic of one of the 1950's era machines that mills the belt sander body and that tool actually incorporated 5 10ER headstocks! There are 10ER and Mark V headstocks incorporated all around the factory, and those old tools that were designed during the Magan era always fascinated me. Scott

Agreed, those were very interesting to watch. Thanks for the good work, Scott.

thedovetailjoint wrote: ↑Fri Dec 03, 2021 3:52 pm IMG_0723.jpg
I got to tour the factory with Jim earlier this week and the fixture that they now use to align the tabletop is super-clever. It is done as they attached the tiebar assembly to the table, prior to the table even being mounted on a Mark 7. You and I would mount a blade or sanding disc or alignment plate on the headstock, but they don't even need to bother with that thanks to a fixture that Jim developed. Likewise, the rip fence is assembled and calibrated on a fixture that features a sliding dial indicator. I really wanted to snap pictures, but understandably it wasn't allowed. Jim did allow me to snap a pic of one of the 1950's era machines that mills the belt sander body and that tool actually incorporated 5 10ER headstocks! There are 10ER and Mark V headstocks incorporated all around the factory, and those old tools that were designed during the Magan era always fascinated me. Scott

This is not hard to envision. Table alignment simply involves orienting the main table to the trunnions which in turn orients the table tie bar (and legs).

Doing factory alignment this way does require some faith in the precision of the carriage and headstock.

I do find it very interesting that factory criteria for table alignment is as loose as .01" over 10" but, after all, this is not a prevision milling machine we are talking about.

I do find it very interesting that factory criteria for table alignment is as loose as .01" over 10" but, after all, this is not a prevision milling machine we are talking about.

That is true but most commercial table saws I am aware of maintain a much tighter tolerance.

I looked at the procedure for aligning miter slot to blade on a relatively high end 10" cabinet saw: https://www.sawstop.com/images/uploads/ ... _300_2.pdf starting on page 63. Two procedures are provided. The first relies on somewhat more measurement equipment than a combination square and says it will produce accuracy of +/- 0.002" over what I'll estimate to be about 7". The second relies on only a combination square or calipers and claims accuracy of +/- 0.010" over the same distance, somewhat worse than Jim's stated factory alignment for the Mark. I found it interesting, but don't understand the results.

- David