Copper Spinning and Chamber

One of the things to avoid with the vacuum chamber is putting too much weight on the top shelf of cart which can only support 250lbs.  The vacuum chamber is roughly 150lbs and the next heaviest component is the acrylic window(s).  If acrylic weighs 0.0426lbs per cubic inch (apparently), then the rough weight of the front window will be about 40lbs, assuming a 30″ by 32″ square 1″ thick piece.  That leaves about 60lbs for everything else including ports, DUT and other variables.  I may end up putting a strut under the upper shelf to add support.

The replacement L gasket has been ordered and I also purchased gas springs off eBay to keep the acrylic window from opening too fast.

I got quotes back for metal spinning the copper cavity and the first one came back at $2400 for the mandrel and then roughly $400 per cavity after that.  Too rich.  I am going to attempt to build the cavity in three pieces by strapping everything in place around the wood mold I already have and then soldering all the seams.  If the tolerances are not good enough, then I will think about going the metal spinning route.

I also sent RFQs out today with regards to waterjet cutting the acrylic pieces I need and I am still looking for a preferably local source for the special acrylic drills bits required because regular bits will rip and crack acrylic.

TOF work has also kept me busier then normal this week as we have moved some websites over to a new “private” server and there are hick-ups to sort out.  The good news is that the wiki documenting this project is now much snappier and in the future will be able to handle huge volumes of traffic.

Have a great weekend.  I am off to Jasper for a day-long bike trip.