Truing, As Best You Can, Shopsmith Table Tops

[dusty]

Now I know where it went! I have been looking for a Carriage that I purchased off EBay and I can not find it.

[dusty]

Somewhere in this discussion, it was asked if the face of the end castings were square to the Way Tubes. They ARE NOT. The face of the castings lean inward a very slight amount.

This image is of the Base Arm Assembly that I installed in place of a Headrest. If I must tilt the Way Tubes (to remove the Headstock as an example), I can pull the pin and lift.

[JPG]

IMHO the 'weak link' is the ignoring of the proper function of that set screw and incorrect headrest clamp adjustment.

No question in my mind the Double tilt base castings can provide left-right more consistency. Add the relocation of the way tube set screws to the top(where they are on the '10' BTW) and twisted way tubes becomes less likely.

Since you now have both versions on a machine, could you verify the bench tube to way tube vertical spacing is the same? I assume it would be, but that is not necessary!

BTW tilting right should still be possible with no modifications.

I could tilt right if I was to drive the roll pin out so that I could pull the pin but I don't plan to do that.

Bench Tube to Way Tube vertical separation?

The Way Tubes are separated by 7" (cntr to cntr).

The Bench Tubes are separated by 8 1/2" (cntr to cntr).

The Way Tubes are separated from the Bench Tubes by 7 17/32" (cntr to cntr).

Thank you, but I was not clear!

I was wondering if the newer(M7) one was different from the older one(M5/V), but later realized you did not have a 'newer' one.

I apologize for my not realizing the obvious earlier. All your statements indicated two M5/V base castings.

[JPG]

Somewhere in this discussion, it was asked if the face of the end castings were square to the Way Tubes. They ARE NOT. The face of the castings lean inward a very slight amount.

This image is of the Headrest that I installed in place of a Base Arm Assembly. If I must tilt the Way Tubes (to remove the Headstock as an example), I can pull the pin and lift.

Looks to me like you replaced the headrest with a base casting.

[dusty]

These images are of the Extension Table Legs on the operators right end.

Notice that they are not perfectly perpendicular to the Way Tubes (very slight amount of light toward the bottoms).

Right Front Extension Table Leg.JPG (1.06 MiB) Viewed 1861 times

Right Rear Extension Table Leg.JPG (1.09 MiB) Viewed 1861 times

The aluminum blocks that I am using were milled special for a test project many years ago. They prove to be very useful for projects like this. I trust, without checking, that they are within a couple thousandths of being square.

I could post similar images of the left end but that seems redundant. On my machine, the left side as right on (no light gaps).

PS: It turns out that these two aluminum blocks are NOT perfectly square. The small gaps that were shown here are the result of that. The Extension Table Legs are dead on (90°s to the Way Tubes)..

[dusty]

I am glad to see Dusty's spt bores are perpendicular to the way tubes.(at least one?)

I question whether Jsburger's base castings are.

As I see it, the 'perpenduclarity' of the the elevator bores is not critical(the 0 degree angle is sdjustable).

The same cannot be said for the base castings.(they are not adjustable) I am guessing Dusty's are correct, but think jsburger's are tilted(both the same amount). That would account for the difference when the aux tables are swapped(the base castings when rotated to install on the opposite end would create an equal but opposite tilt.

All conjecture and 'brain' storming.

I do not know if jsburger's spt bores are perpendicular to the way tubes.

Either scenario would produce the results he described.



Regardless I think SS should weigh in on this. We be discussing a 'new' Mark 7!!!!!

BTW My ? re the base assembly tube stops was stupid!!! They are they same pn!!!! Thanks anyway!



P.S. I hope Dusty replaced the base castings on both ends. Be interesting to see it tilt left if not!


However he may be merely replacing the head rest only to prove his theory.[/quote]

I replaced the Headrest (514530) on only one end (the left side). I don't understand why I should even consider replacing the base castings on the other end. As for tilt, there is none. I have not modified the Headrests to facilitate a tilt and I don't really intend to. If I decide that I need to have this machine tilt, I will purchase the double tilt kit.

As for my theory, I needed to remove the Base Arm Assembly from the mix because I believe that the mechanics of the Base Arm Assembly (in conjunction with the Way Tube Tie Bar (504264)) contribute heavily to the inconsistent alignment results that I experience. This maneuver will convince me one way or the other. I have always contended that the Double Tilt configuration was a move in that direction. Even though they won't talk about it, I believe Shopsmith knows that the Base Arm Assembly is a weak link in the Table System. I believe this experiment will show that that weak link no longer needs to exist.

BECAREFUL HERE. The bores that accept the Extension Table Legs are in a device that is hinged (the Base Arm). The vertical position of the Base Arm can be changed with very little pressure. Furthermore, the Base (504145), if not securely attached to the Way Tubes could also contribute to an alignment error.

[dusty]

John, don't tear anything down without taking a real close look at that spare Carriage. If you simply peer into the Way Tube bores you can see that there is a definite difference when comparing the left end to the right end of the bore. The bores are not done incorrectly. The difference in the thickness of the casting (at the top of the bores) is the way the Carriage was designed.

With this Carriage sitting here in front of me, I am trying to devise a simple way to ascertain that the SPT bores are properly situated with reference to the Way Tube bores. If only I was back in a machine shop. I so miss those precision test beds.

[JPG]

I am glad to see Dusty's spt bores are perpendicular to the way tubes.(at least one?)

I question whether Jsburger's base castings are.

As I see it, the 'perpenduclarity' of the the elevator bores is not critical(the 0 degree angle is sdjustable).

The same cannot be said for the base castings.(they are not adjustable) I am guessing Dusty's are correct, but think jsburger's are tilted(both the same amount). That would account for the difference when the aux tables are swapped(the base castings when rotated to install on the opposite end would create an equal but opposite tilt.

All conjecture and 'brain' storming.

I do not know if jsburger's spt bores are perpendicular to the way tubes.

Either scenario would produce the results he described.



Regardless I think SS should weigh in on this. We be discussing a 'new' Mark 7!!!!!

BTW My ? re the base assembly tube stops was stupid!!! They are they same pn!!!! Thanks anyway!



P.S. I hope Dusty replaced the base castings on both ends. Be interesting to see it tilt left if not!


However he may be merely replacing the head rest only to prove his theory.[/quote]

I replaced the Headrest (514530) on only one end (the left side). I don't understand why I should even consider replacing the base castings on the other end. As for tilt, there is none. I have not modified the Headrests to facilitate a tilt and I don't really intend to. If I decide that I need to have this machine tilt, I will purchase the double tilt kit.

As for my theory, I needed to remove the Base Arm Assembly from the mix because I believe that the mechanics of the Base Arm Assembly (in conjunction with the Way Tube Tie Bar (504264)) contribute heavily to the inconsistent alignment results that I experience. This maneuver will convince me one way or the other. I have always contended that the Double Tilt configuration was a move in that direction. Even though they won't talk about it, I believe Shopsmith knows that the Base Arm Assembly is a weak link in the Table System. I believe this experiment will show that that weak link no longer needs to exist.

BECAREFUL HERE. The bores that accept the Extension Table Legs are in a device that is hinged (the Base Arm). The vertical position of the Base Arm can be changed with very little pressure. Furthermore, the Base (504145), if not securely attached to the Way Tubes could also contribute to an alignment error.

Which makes it imperative that ALL clamps be tightly secured when making any 'measurements/adjustments'. That includes the spt clamp, the base clamp...

Repeatability is key!!!

[dusty]

Somewhere in this discussion, it was asked if the face of the end castings were square to the Way Tubes. They ARE NOT. The face of the castings lean inward a very slight amount.

This image is of the Base Arm Assembly that I installed in place of a Headrest. If I must tilt the Way Tubes (to remove the Headstock as an example), I can pull the pin and lift.

Corrected Text!! I installed a Base Arm Assembly (504145 & 5041453) where there had been a Headrest (514530).

Thank you, JPG.

[dusty]

Regardless I think SS should weigh in on this. We be discussing a 'new' Mark 7!!!!!

BTW My ? re the base assembly tube stops was stupid!!! They are they same pn!!!! Thanks anyway!

P.S. I hope Dusty replaced the base castings on both ends. Be interesting to see it tilt left if not!

However he may be merely replacing the head rest only to prove his theory.

You are not going to see my Mark V Model 520 No Tilt tilt either way. The Shorty will tilt but the Mark V tilts no more. Unless, after using it the way it is right now, I find that alignments are incorrect or can not be maintained.

For a very long time, I have been meaning to make this change because I believed that the differences between the Base Arm (504143) and the Head Rest (514530) made a difference in how the whole thing aligned.

This morning, I made that change. I removed the Head Rest (514530) and replaced it with a second Base Arm Assembly (504145 & 504143). I could tilt if I really needed to by simply removing the base arm pin (504291). I chose not to do that for now. The entire transition only took about an hour and a half.