Re: ATM problem with mirror cell

[Ak55c@aol.com]

In a message dated 8/2/00 12:46:51 PM Eastern Daylight Time, 
jhm.van.gastel@mdw.vu.nl writes:

<< When I had the tailgate made, I was afraid that the collimation bolts
 wouldn't have enough grip in the threads in the square tube walls (the
 rungs), so I had a nut welded on top of each of the three mounting holes,
 instead of threading the tubewalls. And now the problem: The welded nut
 construction leads to 3 mm (1/8 inch) of play at the heigth of the top of
 the mirror, due to the movement of the bolt in the nut. So the top of the
 mirror can move 1.5 mm (measured from the center) in each direction. I have
 been thinking to solve the problem with another nut, at the other (bottom)
 side of the tailgate to lock the collimation bolts when collimating is done.
 But I think the collimation will be gone then , because the collimation bolt
 will change possition when the locknut is fastened. And it will give al  lot
 of movement of the supportpoints under the mirror, when I use a sling. When
 I use silicone blobs there will be too much strees on the mirror I think,
 because the mirror will try to hold the cell construction together.
 
 So I think there is no other solution then welding another nut against the
 bottom rungs with the holes, at the opposite side of the holes of the
 collimation bolts, so that each collimation bolt will be held by two nuts,
 about 25 mm from each other.
 
 Does this make sense or is there an other (hopelfully easier) solution?
 Jan van Gastel >>


I would weld a bolt to the bottom.  Think this is the best solution.

Good luck,
scott