The Ohio State University College of Mathematical & Physical Sciences Department of Astronomy

Attendees: Jerry Mason, Ralph Bellville, Dave Brewer, Dave Steinbrecher, Tom O'Brien, Darren DePoy, Paul Byard, Chris Morgan, Dan Pappalardo, Mark Derwent, Pat Osmer, Lynn Nair, & Rick Pogge.

(Full house: this meeting is combined with an Aluminizing project update)

Optics

We have received the invoice from REOSC for the first 2 of 4 collimator mirrors (C1 and C2), after acceptance by Paul and Tom. Once the invoice is paid, we will take delivery of the first mirrors, probably end of October given the usual delays in shipping, customs clearance, etc.

Progress at REOSC on collimators C3 and C4 continues apace, they should be ready for acceptance review later this quarter (late November/early December).

Paul has started to receive replies to our RFQs on optical coatings (see 2003 August 26 report). Still more are expected to come in, so he'll report on that later in the quarter.

Mechanical Fabrication & Design

Mark Derwent has been working with Indian Creek Fabricators near Dayton on work with the upper structures for MODS1 and MODS2. Indian Creek is currently waiting on the delivery of clamps being made at Columbus Machine Works, probably delivered tomorrow.

Mark and Tom will be going out to Dayton on Friday to help them align the upper part of the welding fixture (a piece that looks like the Gregorian mounting ring on the LBT). This is the last step required before Indian Creek can start fabrication of the upper structure.

We have placed an order with a Elyria Metal Spinning & Fabricating Company in Elyria, Ohio for the fabrication of the collmator strut tapers. These are the pieces that mate the carbon fiber struts to the steel framework on either ends. This company uses a special inductive spinning process that produces a part with a uniform wall area along the taper, giving greater strength to this critical part. We had a lot of no-bids for these parts until Mark found out about EMS. Not only do the specialize in this kind of work, but we also got a good price and we get "Buy Ohio" brownie points from the State to boot.

Tom has been exchanging emails with LBTPO regarding the Gregorian interface. He thinks we now have a clear plan for the clamping devices (hammer locks). Issues remaining concern how one guides the instrument into place and docks it. If we are going to dock onto the hammerheads, they need to be made robust enough to serve as "pilots". Tom and LBTPO have in principle agreed upon the requiremetns, we're waiting for a specific bid.

Guide Cameras

Darren reported that the CCDs for the guide cameras have been purchased by Mike Lesser, the various parts are being machined, and they will start assembling guide cameras. We are slated to get one of the first units plus a control computer with all the necessary software, hardware, and liquid cooling system. Also, we have learned that the Potsdam team has sample microlens arrays ready to ship to Mike for bonding onto the CCDs for the wavefront sensor cameras.

MODS Contract Documents

Rick and Eric Monier completed the draft MODS contract documents, and forwarded them to Mark Wagner at LBTPO on September 15. These will form the basis of future discussions with LBTPO.