Drill press mode table alignment

jmadden · Post by **jmadden** » Wed Apr 10, 2013 7:42 pm

For the first time I decided to align my table in drill press mode. Following Sawdust Session #22 - "Truing the table to the drill chuck", I made a gig similar to what Nick had made except I used a 3/8" X 1" aluminum bar 9" long. Using a dial indicator attached to one end of the bar, I measured the left and right sides of the table, finding the right side to be 0.051" lower. I then located two 3/8" fender washers that were both 0.050" thick. I removed the bolts on the right side trunnion and installed the washers/shims. Tightened the bolts, reinstalled the table and re-measured. The right side is still 0.032" too low. What is wrong?
Background - this is a 1979 Mark V with the 520 table upgrade and Power Pro headstock upgrade. The upgraded table has never had the trunnion bolts removed before this. The bolts have just been loosened to align the miter slots with the blade.

JPG · Post by **JPG** » Wed Apr 10, 2013 9:24 pm

Were ALL locks tightened down BOTH times?

Realize the bar is 9". The 'right' trunion is how far from the quill axis?

Were the trunions snug to the table at first?

jmadden · Post by **jmadden** » Wed Apr 10, 2013 9:36 pm

Yes, everything was tight to begin with and after the shims were installed.
The jig bar is 9" long but the way it is assembled, the dial indicator is 7" from the drill chuck. This places it directly over each trunnion.

dusty · Post by **dusty** » Thu Apr 11, 2013 5:44 am

Don't be alarmed at that.Get an assortment of washer and shim away. When I finished, I had washer on three of the four trunnion bolts.

When you get all done, do a complete table alignment just to make sure you haven't messed up along the way. There is one good thing. Once you have done it correctly, you'll never have to do it again unless you remove the trunnions from the table.

jmadden · Post by **jmadden** » Thu Apr 11, 2013 9:47 am

Thanks for the advice. I do have a large selection of washers to play with.

jmadden · Post by **jmadden** » Fri Apr 12, 2013 10:25 am

Finally figured out the problem. In drill press mode my table was not exactly perpendicular, front to back, with the drill chuck. Therefore, when measuring side to side if you don't turn the measuring jig exactly 180 degrees you have a bad measurement.
Another thing that may have been giving me some issues was not loosening all 4 trunnion bolts. By just removing the two bolts to install the shims and not loosening the other two bolts, I may have been putting some stress and twist in the table.
That all said my table is now dead on. Yes, less that 0.001" difference side to side. Now I hope I can keep it that way when I align the miter slots with the blade.

dusty · Post by **dusty** » Fri Apr 12, 2013 10:48 am

jmadden wrote:Finally figured out the problem. In drill press mode my table was not exactly perpendicular, front to back, with the drill chuck. Therefore, when measuring side to side if you don't turn the measuring jig exactly 180 degrees you have a bad measurement.
Another thing that may have been giving me some issues was not loosening all 4 trunnion bolts. By just removing the two bolts to install the shims and not loosening the other two bolts, I may have been putting some stress and twist in the table.
That all said my table is now dead on. Yes, less that 0.001" difference side to side. Now I hope I can keep it that way when I align the miter slots with the blade.

I am confident that it will remain in alignment once you have it there which you say you have achieved. Congratulations. That can be a very cantankerous procedure.

What did you have chucked? How did you measure to determine alignment? left/right, front/back, all four corners, what?

After finishing drill press mode, was the main table still square with the blade or did you have to redo that?

jmadden · Post by **jmadden** » Fri Apr 12, 2013 12:54 pm

Front to back I used my Wixey and a 3/8" aluminum rod. For left to right I made a jig from 3/8" X 1" aluminum bar, 3/8" bolt with head cut off and a dial indicator on the opposite end. After finishing the drill press mode alignment the main table had to be realigned.