[Jeff, Daniel]

I tightened the 10" to 4.5" zero length reducer flange on top of the vacuum cube.

We added the CF0600S2 6" to two 2.75" CF Multiport Reducer to the 10" to 6" CF Zero Length Reducer. We did the usual method of placing the flange using some top screws to hold it, adding 2 bottom screws, remove the top screws, tilting the flange up, dropping in the gasket, and then adding the remaining screws. Only a few screws were accessible with our torque wrenches, so I tightened the screws by hand in a star pattern (going every 5 screws with 16 total). We bought this part (as part of a set) so that the torque wrenches can reach all the screws.

We took off a plastic cover and cleaned the 10" to 4.5" reducer flange, which was covered with duct tape (and duct tape residue) outside where the 4.5" flange goes (and outside the vacuum). 

We added a 4.5" CF blank flange to this 10" to 4.5" reducer flange on top of the vacuum cube. Because there were only 8 screws, I started at a lower torque, 6 N m, did a star pattern every 3 screws so that every screw was tightened twice, and incremented the torque by 1 N m until the torque was 12 N m, then I incremented the torque by 3 N m until 34 N m when the flange seemed tight enough (stainless steel contact around ~70% of the surface).

We added a 2.75" CF blank flange to the CF0600S2 (where the laser view port will not go) and attached it with the plate nuts. I lightly torqued by hand and used the torque wrench starting at its minimum value of 6 N m. I tightened every 2-3 bolts until the torque wrench did not tighten the bolts further, then incremented the torque by 1 N m until 14 N m. For the laser viewport, we will use the annealed copper gasket, which will require less torque to tighten.

Next, we will swap out the 10" to 2.75" reducer flange for a 10" to 4.5" reducer flange because the 10" to 2.75" flange is needed for the demonstrator IFO.