- Correct the pitch and roll by just rotating the dome (redrilling the mount points). Assume there are no errors in the redrilling.
- Redrill the mount points to just correct the average roll error, and then reshim the elevation rails from 10 to 20 degrees za. Assume a residual error on redrilling of .02 degrees and a shimming error of .04 degrees. Do not include the focus change caused by the shimming (note.. after the fact, jose maldonado said that they could probably redrill the dome holes to 1/16 of an inch. Over the 12 foot span this is about .025 deg).
- Redrill the mount points to correct the roll by .12 degrees. Shim the elevation rail to remove a linear pitch from za=10 to za=20 of .14 degrees. Assume it is done exactly. Include the focus change caused by shimming the rails.

Figure 1 Top: This is the pitch and roll before (solid) and after (dashed) the redrilling of the mount points. The pitch correction of .04 degrees and roll correction of .12 was chosen after trying various combinations.

- Figure 1 Center: This is the tiedown position needed to correct the pitch,roll, focus error before and after the redrilling. The tiedown limits are overplotted in blue.
- Figure 1 Bottom: The tension in 1 tiedown block before and after redrilling. The limits are +120 kips and 0 kips (a blue line is drawn at 5 kips for reference).
- Figure 2 plots the tiedown position (top), tension in one block (center), and total tension in the 3 tiedowns (bottom) for temperatures: 60, 70, 80, and 90 degrees F. At 60 deg the tdPosition limits are hitting (tiedowns all the way down). They are also hit (on the other side) at temperatures of 90 def F at 19 deg za.They start to lose tension around 17 deg za for 90deg F. At 60F the total tension limit of 240 kips is exceeded.

- Figure 1 shows what you get by just reshimming the elavation rails above za=10 deg. Top: The current pitch versus za is plotted as the solid black line. The red dashed line is the pitch corrected so that the average pitch error above 10 degrees za is +.04 degrees. The dashed green line is the same with the average pitch set to -.04 degrees. At each za is a complete az spin worth of values. The range of the vertical lines is what is meaningful (the horizontal lines are just the values at az=0). .04 degrees was chosen as a "reasonable" shimming error (although there hasn't been any feedback from the people that actually have to do the work).
- Figure 1 Center: This is the tiedown positions to correct for the 3 options: current (black), +.04 average pitch (red), -.04 average pitch (green). It was computed for 72 deg F (the tiedowns need to move 1.7 inches for every 5 degrees F). The horizontal lines are the tiedown limits. It is illegal to cross a limit (and they do!). There is also a large vertical range used at this 1 temperature which means that the temperature range where it could work is small.
- Figure 1 Bottom: The tiedown tension in kips (for 1 block) for these three settings. The maximum allowed value is 120 kips. The minimum should probably stay above 5 kips to insure that we don't lose tension in a cable.
- Figure 2 has the roll error and then the results from reshiming for pitch and rotating for roll. Top: This shows the current roll (black) and the roll after setting the average roll to +.02 deg (red) and -.02 deg (green). This would be done be redrilling the holes for the dome mount. The tighter spec of .02 deg was used because it should be easier to redrill the holes than shim the rails. Of course this ignores the fact that to reshim the pitch you mess with the current roll.
- Figure 2 Center. These are the tiedown positions for the current error (black) and then the four permutations of (pitch,roll) corrections: (+.04p,+.02r Red), (-.04p,-.02r Green), (+.04p,-.02r Blue), (-.04p,+.02r pink). The vertical range needed has decreased appreciably. The only permutation that exceeds a limit is the green (-.04p,-.02r) above za of 16 degrees.
- Figure 2 Bottom. The tensions on a single block for the 5 choices. None of them will cause a problem at 72F.
- Figure 3 Top. The (+.04p,-.02r Blue) option of figure 2 was replotted for temperatures 60,70,80,and 90 degF. This option works better than the others in colder weather. At 60deg F the tiedown limit is exceed (tiedowns are pulled all the way down).
- Figure 3 Center: The tension on a tiedown block is plotted for the same option for temps 60-90 F. At 90F the cable will start to lose tension at za=17 (before it hits the motion limit). At 60F the tension gets up to about 105 kips (120 kips lifts the block).
- Figure 3 Bottom: This is the total tension on the platform from the tiedowns versus za for the 4 temperatures (it should be horizontal lines, but the model isn't perfect..). The maximum permitted tension is 240 kips. We hit that at 60 degF.

Using the radius of 869.781 feet the platform is too high. Adding weight to the platform could give us more range at lower temperatures. Before doing this we should verify that the shorter radius of 869.781 is correct (the focus curves we've done do not support this).

The shimming will modify the focus by up to 1 inch at za=19.5 degrees (this has not been included here).

- Figure 1 has the data for 72 degrees F. There is a linear ramp in pitch (10->20deg za of .14 deg). The average roll has also been removed by rotating the dome (.12 degrees). The change in focus from the shimming has been included.

- Figure 2 plots the data for temperatures 60,70,80, and 90 F. The position limits are hit at 70F at za=5 and the kips go to < 5 kips for temp=90F. The total kips at 60F is greater than the allowed 240 kips.

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