Interesting! You have critiqued a discussion re .01 and .001 degree accuracy with a device accurate to .1 degree(+-.05 degree).dusty wrote:Not to nitpick but actually my need to average the numbers does not indicate non linearity. If non linearity was the issue, each and every reading taken would be off by some amount always in the same direction. Your input shows that. As you progress from 0 degrees to 45 degrees the sine increases from .01795 to .70710]it never jumps backward[/U].
Now you did not see my actual numbers so I know you were not made aware that the numbers were inconsistent but you did jump to your conclusion without checking.
Now, having said all of that - when I noticed that the numbers were inconsistent, I made some modifications to my collection methods. I increased the size of the adjustment know and created a rudimentary scale that better allows me to turn the knob in more consistent increments.
With the modified knob, 1 revolution of the knob results in a .1 degree change in table tilt with only occasional deviation. I contribute that deviation to the Wixey - remembering that the Wixey is accurate to .1 degree. I have retested this from 0 degrees to 35 degrees. I am satisfied that this works sufficiently well for all of my tilting table needs. Enough is enough.
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BTW did you keep the threaded rod at a 90 degree angle to the way tubes? It would have to move horizontally parallel to the way tubes.
A way(maybe impractical) to compensate for the 'non-linearity' would be to position the threaded rod at the same angle as the table but in the opposite direction. This would cause the rod length adjustment to be tangential to the arc created by the table rotating thus providing a 'constant' tangential distance moved independent of the angle. [Think rod ALWAYS perpendicular to the table!]
