Mark V Alignment

dusty · Post by **dusty** » Fri Sep 10, 2010 10:59 am

We all do alignments of some sort on the Mark V but do we all do the same alignment? I seriously doubt that. I know that I do not follow the generally recognized procedures but that does not count because I play a lot with the machine.

There is one outstanding requirement for all of the alignments. The main table must be aligned to the blade for operations in the horizontal mode and to the the drill bit in the vertical mode.

Both of these alignments are likely to require that the table be repositioned to achieve the desired objectives.

Is there a requirement to do one of these alignments before the other is attempted. If so, which should be done first.

BigSky · Post by **BigSky** » Fri Sep 10, 2010 1:02 pm

dusty wrote:We all do alignments of some sort on the Mark V but do we all do the same alignment? I seriously doubt that. I know that I do not follow the generally recognized procedures but that does not count because I play a lot with the machine.

There is one outstanding requirement for all of the alignments. The main table must be aligned to the blade for operations in the horizontal mode and to the the drill bit in the vertical mode.

Both of these alignments are likely to require that the table be repositioned to achieve the desired objectives.

Is there a requirement to do one of these alignments before the other is attempted. If so, which should be done first.

I do not know if there is a requirement for any specific order but I align:

1. main table
2. extension table
3. floating tables
4. main table in drill press mode

wa2crk · Post by **wa2crk** » Fri Sep 10, 2010 1:39 pm

Dusty;
I believe that all adjustments should be made to the main table first. Al of the other alignments are dependent on the main table being correct. Align the miter gauge slots first and then the tilt angles of the table. One of the methods to check the table in the drill press position is as follows,
first make sure that the table is flat using a straight edge. I use a 4' level
remove the table insert
place the table (only) in the drill press position the machine remains horizontal
remove the saw blade and the saw guard and then replace the blade without the guard.
position the table height so that the saw arbor will pass through the center of the table.
position the table along the way tubes so that the blade is about 2" from the surface of the table
now strike the saw blade with a piece of wood so that the sawblade rings like a bell.
while the blade is ringing, slowly advance the quill until you hear a raspy sound from the saw blade and stop and lock the quill.(the raspy sound occurs when one of the teeth of the sawblade touches the table)
now check the relationship of the blade to the table top. The saw blade teeth should be virtually touching the table around the entire circumference of the blade
This will verify that the table is 90 degrees to the quill not only in the vertical but also in the front to rear and all points around at least a 10" circle and that the table is 90 degrees to the axis of rotation at all points around the circle
If the gap between the saw blade and the table exceeds 1/64" I would shim the table and repeat the test.
Remember that the machine remains in the sawing position and only the main table is moved to the drill press position and, of course, the machine is UNPLUGGED.
Bill V

dusty · Post by **dusty** » Fri Sep 10, 2010 2:00 pm

I like the bell ringer test, Bill. I just tried it. Anxious to see how my table alignment checked when tested this way. It failed!

Well, I don't know that because I don't know what the criteria is for pass/fail .......adjust or leave alone. At a quick glance, I can see that the saw teeth do not all touch the table. What criteria do you apply? I guess I am asking you to quantify "virtually touching". Do you propose to test/inspect every tooth or just selected ones?

If I rotate the blade (I will scratch the table) but will the relationship between saw teeth and table surface change when I do? I think yes based on degree of runout.

CAUTION: :eek:If you scratch your table doing this, you have already been warned!:eek:

BTW I was a bit surprised by just how rich that blade rings when tapped with the handle of the allen wrench.

I gotta think about this (the results that is) because I would have told you my table was square to the drill bit. This test would indicate that it is not.

I assume that shimming between the table and the trunnion is the alignment method.

wa2crk · Post by **wa2crk** » Fri Sep 10, 2010 3:03 pm

Dusty;
I think that down at the end of my post I suggested that more than 1/64" I would consider excessive but only by my standards. The test with a drill bit will only show that the table is 90 degrees in the vicinity of the drill bit but not how flat the table is and also not how flat and true the table is. Making the table surface equidistant from the body of the blade is more accurate. IMHO Most saw blades are true to .003". This means that the saw blade is 90 deg to the axis of rotation of the spindle due to the geometry of the machine and that the table when in the drill press mode is equidistant from the saw blade at all points around the blade (top to bottom and front to back) will also be 90 degrees to the axis of rotation. Making the table true over the 10"circle is similar to the difference in the sight picture of a rifle compared to the sight picture of a pistol. Measuring over a greater distance reduces the error
You are correct that shimming the trunnion contact points is the method to make the table true to the blade
Bill V

pennview · Post by **pennview** » Sat Sep 11, 2010 8:50 am

The first thing I align on the Shopsmith is the main table to the spindle in drill press mode. This would be the left-to-right table adjustment using shims between the trunion and table to square the table to the spindle. While still in drill press mode, I then do the front-to-back table adjustment using the table stops to square the table to the spindle. If you want to drill holes perpendicular to your work piece, you need to make these adjustment as accurately as possible.

For the shims you can use washers, or cut them from brass shim stock or soda pop cans, or use whatever thin material works to bring the table into alignment with the spindle. If you drill or punch holes in the shim material, they'll stay in place while making later adjustments. Some of that plastic adhesive backed label tape works well too.

To check the alignment you can use a wire coat hanger bent into a modified "Z" shape that is mounted in the drill chuck, rotating it to verify that the table is square to the spindle. I have a TS-Aligner Jr that uses a dial indicator to check alignment.

Then in sawing mode comes squaring the table to the saw blade, then aligning miter slot to the blade, and then fence to blade/miter slots. Then come alignment of the auxiliary tables.

dusty · Post by **dusty** » Sat Sep 11, 2010 1:24 pm

I took a couple of your suggestions as offered in this thread and rechecked my table. I have always been a little bothered by inaccuracies created in drill press mode. I found that it was not as perfectly aligned as I thought. It was right on corner to corner in one direction but significantly off corner to corner on the other diagonal.

Shims. I gotta install shims. Easiest way to do that is see what is there and compare to what appears to be required.

Guess what - no shims. Did I ever do this alignment????

Based on measurements taken, I decided to put two shims on each of the studs on the one diagonal and a combination on the other. One shim on one and four shims on the other. The shims all measure dead on at .005".

With the trunnion removed putting shims in place was rather easy. The results are not perfect but much better. I'm going to work with this for a while and then if changes need to be made - I now know how.

Rather than a saw blade, I used something I put together back when Nick was doing the Sawdust Sessions. It allows a check all the way around the drive shaft with no teeth to scratch the table.

[ATTACH]10356[/ATTACH]

[ATTACH]10357[/ATTACH]

A feeler gauge was used to measure the space between that aluminum bar and the table surface at about eight different locations. I've got one corner that is about .033" and it's diagonal drags on the table. In the other diagonal the measurements are identical at .002".

I'm a little confused because of past observations. I have long thought that I had a slightly low corner on the table but I don't see that reflected in these numbers.

JPG · Post by **JPG** » Sat Sep 11, 2010 5:19 pm

I had never thought of checking/shimming the table for vertical drill press mode prior to the other adjustments. This is for all intents and purposes the opposite sequence that I have followed in the past.

One question is nagging me! How does one distinguish between a need to shim, and a need to adjust the table stop(s)? Seems to me they are not independent!

Ed in Tampa · Post by **Ed in Tampa** » Sat Sep 11, 2010 7:48 pm

dusty wrote:I took a couple of your suggestions as offered in this thread and rechecked my table. I have always been a little bothered by inaccuracies created in drill press mode. I found that it was not as perfectly aligned as I thought. It was right on corner to corner in one direction but significantly off corner to corner on the other diagonal.

Shims. I gotta install shims. Easiest way to do that is see what is there and compare to what appears to be required.

Guess what - no shims. Did I ever do this alignment????

Based on measurements taken, I decided to put two shims on each of the studs on the one diagonal and a combination on the other. One shim on one and four shims on the other. The shims all measure dead on at .005".

With the trunnion removed putting shims in place was rather easy. The results are not perfect but much better. I'm going to work with this for a while and then if changes need to be made - I now know how.

Rather than a saw blade, I used something I put together back when Nick was doing the Sawdust Sessions. It allows a check all the way around the drive shaft with no teeth to scratch the table.

[ATTACH]10356[/ATTACH]

[ATTACH]10357[/ATTACH]

A feeler gauge was used to measure the space between that aluminum bar and the table surface at about eight different locations. I've got one corner that is about .033" and it's diagonal drags on the table. In the other diagonal the measurements are identical at .002".

I'm a little confused because of past observations. I have long thought that I had a slightly low corner on the table but I don't see that reflected in these numbers.

There was a variation of this a while back using a bent coat hanger.
Basically you bent the coat hanger into a z shape. Chuck one end in the chuck and adjust the quill until the hange just touches the table.
Then slowly turn the chuck. When the coat hanger gets to the highest point stop and readjust the chuck until it is just touching and then measue the gap around the table and figure out what shims you need where.
Worked for me and I think I got my table level to the chuck.

Caveat I do believe shims between the table and trunion can cause the table to warp. Just my opinion didn't say or imply anything bad about Shopsmith... heaven forbid

dusty · Post by **dusty** » Sat Sep 11, 2010 8:38 pm

I believe that the shims, in conjunction with how you torque down the trunnion bolts, probable does twist the table. It seems to me this was the purpose of this table shimming endeavor. If not, it worked anyway. My table is now more true to the drive shaft than it ever has been.

I think that I can probably now drill holes in my aluminum plates that will be perpendicular to the plate. I could not get them correct before and I had to take them to a machine shop. Metal work is now as forgiving as woodwork.