Shopsmith Restoration Episode 15: OK...Everybody Line Up!

Well, it all has come down to this: the hardest part of restoration….getting things to line up correctly.  It is one thing to scrape, sand, dismantle, clean, and reconstruct.  But to make sure the table and fences are perpendicular and square with the world, or at least with the headstock, is quite another story (well I suppose this story).

I used three reference sources for this alignment phase:

• Premier Sawdust Session video Aligning the Mark V Table  (www.shopsmithacademy.com/Sawdust_Sessions.htm).  My Shopsmith is not a Mark V, but the technique was helpful.

• Sawdust Session #22: Truing the Table to the Drill Chuck.  Here, I am curious of how he leveled the table with shims (the video is too grainy to see exactly what was going on).  In addition, what affect will aligning the table with the drill chuck have on the initial alignment of the table with the saw blade?  Is this an iterative process?

• An old document by Magna Engineering titled Shopsmith Adjustments.  This resource was the most valuable of the bunch, although it didn't address alignment with the drill chuck.

ALIGNMENT OF THE TABLE WITH THE SAW:  PARALLEL WITH THE MITER SLOTS

I measured the table miter slots against the saw blade using a digital caliper.  The table was off by over .020".  

I loosened the bottom bolts, nudged the table slightly, and remeasured.  

Looks good...but this may change once I test the table against the drill chuck.  

ALIGNMENT OF THE TABLE WITH THE SAW:  PERPENDICULAR WITH THE SAW BLADE

If you look closely at the picture, there is daylight between the angle and the top of the blade (not good).  The way to fix this is through adjustment of the trunnion mounting.  

Now here's where it gets interesting (read: frustrating).  I loosened the trunnion nut which allows the table to rotate freely.  There is a stop lever which  automatically locks the trunnion at standard positions, such as 0⁰, 45⁰, etc.  At 0⁰, the table should be perpendicular to the blade….but it isn't.  

Pressing the stop lever releases it from the trunnion so I can nudge the table into the correct position (by watching the square), then retighten the trunnion nut to lock the table into position.  The next step is to loosen the stop lever (as the photo shows) and tweak it such that it now locks into the table's stop groove, and then retighten the stop lever.  

I tested this by loosening the trunnion, rotate the table around a bit, then back to the automatic 0⁰ position stop.  unfortunately, it moved back to its original off-angle position.  

Phooey.

I tried this process again, and again.  I finally came to the conclusion that there is too much slop in the stop lever to get this table right on the mark.  I'll have to check and adjust this each time I position the table for a saw cut (probably not a bad routine to get into anyway).

Well, that was fun - let's move on to the alignment with the drill chuck.

ALIGNMENT OF THE TABLE WITH THE DRILL CHUCK

The key here is to ensure the table is perpendicular to the drill chuck in two directions: front-to-back (looking at the front of the drill press), and right-to-left.

The front-to-back alignment is the same situation as above - adjusting the trunnion nut and the stop lever - this time at the 90⁰ stop mark.  

The left-to-right alignment (as facing the drill press) is critical because it would require adding shims to the table mounts if the alignment is off. 

Using the alignment process as shown in the Sawdust session, I fabricated an alignment jig using a straight piece of wood with a bolt through one end and inserted into the drill chuck.  Using digital calipers, I measured the distance between the end of the jig and the table while rotating the jig/chuck assembly from one side to the other.  I tried this a couple of times, but kept getting inconsistent readings each time.

Then I had an epiphany: why not use the Carpenter app on my iPhone to measure the slope of the jig compared to the table? (the screen provides a traditional bubble plus a digital readout of the angle).   I found that the jig was not square with the drill chuck, so on one side, it measured +5^o but when rotated to the other side shows -7⁰.   What the hey.  So now I have to use some sort of math problem to figure out the correct table position?  I DON'T THINK SO!

Apparently, the jig idea is not going to work for me.  If I had a drill press which could drill a hole straight and true, then maybe the jig would work.  I clearly have a chicken and egg situation here.

Plan B:  The sawdust session says don't use the saw blade, as it may not yield a true measurement when using the drill chuck….so I use the saw blade to test the table alignment anyway.

Using the iPhone app again, the saw blade and the table measured the same angle, within 0.002".  Good enough in my book, and a good sign that the table does not need a shim adjustment (**WHEW**).

I changed the saw blade for the drill chuck with a decently long drill bit, and used a carpenter's square again to double check the alignment.  It looked good. 

I repositioned the Shopsmith back to the table saw position, manually checking the proper 0⁰ position and made some test cuts to check the final alignment.  The photo shows the results of a horizontal cut with one side flipped 180⁰ after the cut.  I'm satisfied.

The Shopsmith seems ready for doing actual work, and making sawdust.  

The auxiliary table needs to be aligned...but I'll need to do that each time it is removed and re-installed.

There are a few remaining cleanup activities still required, such as the sanding disk, the fence, and finally the jointer - which is going to be a major effort in itself, and good fodder for another blog some time in the future (but not now).