<p>By 16:40 I mounted all three chamber lids.</p>
<p>The central chamber lid includes the diode detector mount, the iris, a vacuum feedthrough, and an actuator with no hook.</p>
<p>The downstream chamber lid includes a vacuum feedthrough and an actuator with no hook.</p>
<p>I then mounted the target holder actuator with its two aluminium boxes.</p>
<p>I noticed the sides of the boxes were not trimmed down since my last visit in July 2017. So again I needed to remove washers from the bolts directly below these boxes, which are used to connect the beamline and turbo sections of the target chamber. I also noticed the hole of the aluminium box which the target actuator arm sits was not enlarged since my last visit, and so is not large enough to fit a standard 16mm o-ring centering ring. Instead a smaller centering ring is used which means the actuator arm is not centered, for the vacuum tests this isn't a big problem.</p>
<p>Note: when I mounted the target actuator I replaced its 80mm (total length) Al tube with the 60mm (total length) Al tube, this should allow access to all target positions.</p>
<p>After some further setup on the beamline - including checking the turbo pumps were being water cooled - we were ready to start the vacuum test.</p>
<p>At 18:00 we started the roughing pumps</p>
<p>At 18:10 we started the two upstream and two downstream turbo pumps</p>
<p>At ~18:18 the chamber up and chamber down readings were at low 10^-4 mBar, we would've expected lower pressure readings due to the power of the pumping system. We suspected a leak and switched off the pumps.</p>
<p>Lucio noticed the 70mm screws mounting the lids and collar to the rest of the chamber were too long, and either needed to be shortened or additional washers used - otherwise we could heavily damage the chamber thread</p>
<p>At the end of the day we learnt Fillipo will be in the lab tomorrow (saturday 17th) between 9:00 - 13:00, and agreed that I (Thomas C) could come in and connect the electronics cables ready for next week.</p> |