We had another good point today in the lab. One of the computers arrived earlier in the week and I installed linux in preparation for use. We got the proprietary software, SPEC by Certif, to control the diffractometer over the weekend. It’s the same software package I saw at Argonne and to a lesser extent in graduate school (though we didn’t need it for the SAXS-speckle experiments).

I am thankful for that experience as having to learn it at this point would require a major undertaking. Granted I’m still “learning” it, but I’m more or less able to function on my own. That goes double for having spent so much time learning linux in graduate school. Anyways, the software compiled and installed with not even a hiccup.

But we did much better. I managed to hook up a couple of motors to the controller/driver electronics, a couple of old MCU-2 racks from Advanced Control Systems. I can control the motors manually direct from the front panels, but the fun thing was to get those communicating with the linux box running SPEC. Now I can control the motors straight from the computer. From here I can control the number of steps/sec, the number of steps/degree, etc... and drive the motors to arbitrary positions.



A very large part of a diffractometer comes down to being able to control the motors with a high degree of precision and reproducibility, and all of it with a computer. So in essence, we’ve demonstrated this as a solved problem and it’s just a matter of repeating that solution in a few forms.

The MCU-2 units are sort of the “backup/extras”. For the primary 4-8 motors I’ve already purchased a nice set of modular step-pak controllers. That should give me a total of 12 controllable axes from the computer. That sure beats standing around inside a hutch turning a dial!

Progress today.

The electrician has begun installing the power cables, outlets, breakers, and conduits in the lab. The lab space itself is generous, but it was obvious from the first day that we’d have to make some significant expenditures to install some basic upgrades to make it a research lab. Electrical wiring was one of the biggies.

We need a primary power source for the x-ray generator. The unit we’re starting with is a 220V-50Amp, but single phase. However, we’re planning to upgrade at some point so we’ve done the wiring for a full 3 phases s the additional cost was marginal and right now it’s easy to install. We also had additional 220 single and 3 phase outlets, plenty of GFICs, and an emergency kill switch right by the front door.

A large part of the last several weeks has been spent ordering equipment (and making sure it’s the right thing before ordering!). I have become very familiar with our purchase request form, as well as our support staff responsible for placing the orders. I am not above bribing her with espresso so that not all of our interaction is based around me making more work for her.

This period of time involves lots of planning, both short and long term.

For instance, I’m going to build an x-ray hutch. And this isn’t your father’s Oldsmobile style table top x-ray enclosure/hutch. No, no... this is a full sized, walk-in, large hutch capable of housing a large diffractometer. So, how big do you make the hutch? Well, funds are finite, so “as big as I want” isn’t an answer. But, making it big enough to eventually house 2 different sources and hutches is reasonable. Especially as building a large single hutch is much less than building a second hutch later on.

But it’s not just finances and logistics either. There are two different basic philosophies here. One, push everything as close together as possible and use no focusing. You’ll use a flat mono-chromator, minimize the total flight path, make alignment simpler, and have less attenuation from air-scattering of the x-rays. There are down sides too though. Frequently in this scheme your sample will only select a portion of the x-ray beam instead of the entire thing. The other philosophy is to move things out a bit, use a curved mono-chromator, and have the beam focused to a small size at the sample. This can increase the number of x-rays (assuming you’ve taken care of that nasty air-scattering) on the sample, lower backgrounds, and allow for more powerful selection of smaller regions of your sample. The price here is increased complication in set up and, often, requires more frequent “fine tuning.” So, that simple decision can mean a couple of extra meters of distance (or the other complication of having the source outside the hutch). Nothing is simple!

In my case I’ve opted to “supersize” the hutch, but to go with the shorter instrument geometry.

That also effects other things. Do I need 1 optical table or 2? Can I get a spare vacuum pump easily? Do I design the flight path to be evacuated (or filled with helium)? So many things to decide... and it needs to be in my head before placing the orders!

The 2nd worst thing to a completely empty lab, is a half filled lab where the budget has absolutely run out. So in the back of my head is always the idea that I need to make sure we get this instrument completely working before I spend too much money on other equipment and projects.

One very fun aspect of this is that I get to do much of the reading and work for this at home at night. As such Linus gets to help.

In one of the most bizarre set of circumstances, a major portion of my x-ray equipment arrived today. It was driven up from NJ, in a stretched limo. My equipment has now spent more time in a limo than I have.



They own a limo, for deliveries and service calls. This is awesomeness that is beyond compare.

Step one, get space, support, and funding.

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I’ve decided to add a little section to the reciprocal space blog to match a large project that is going on right now. Namely I am at the very first part of my “start-up” phase at RIT and am building my own X-ray Diffraction Lab. This is important for a large host of reasons, but is also a great deal of fun.

I suppose the first part of making an XRD lab is first to find a place that wants you to make one! Just getting to this point was no small feat and required a great deal of work. I’m recalling the phrase attributed to Archimedes, “give me a place to stand, a lever long enough, and I will move the world.” There’s a clever twist to be made from that but, to be honest, I’m too tired to put it together fully. Regardless, just getting to the point where you have this is a big step :






and



What you see there is my lab. Or what will be! There’s still a bit of cleaning to do, but it’s a generous space. You can date the lab by some of the hardware and equipment that’s visible. The line of boxes is a collection of things that we’ll be sending off for surplus after it is looked through by the appropriate people. Actually as I write this there are a few things already going in, but I’m behind at updating the blog.

Much of my own equipment is already on order, but has yet to arrive.

It’s easy to think of “research” related items. All the important things to making an x-ray source are pretty familiar to me by this point. But the new thing is thinking of all the things (tools, parts, infrastructure) that were already in place when I joined my thesis adviser, then later when I joined Argonne. It’s simple things that I forgot about initially. “Oh yes, I need to get some desks and chairs in here.”

It’s also been interested to see the equipment that are being donated both from individual faculty members, outside colleagues and friends, but also at a department level. I’ve been reticent to accept much in the way of old electronics, but other things are much safer. However I suspect it’s only a matter of time before I break down and take someone’s old NIM bin (please help commit me if I actually take a CAMAC/VME crate). All the time in the back of my head is the knowledge that my start up funding (while very nice) is finite. So especially until I have a major working instrument (x-ray source, diffractometer, and working electronics to control it/take data), I will be quite miserly.

There is also a danger in the above pictures. It is absolutely necessary for the lab to pass through an “empty” phase. But that empty phase cannot last long at all. It is imperative that I get the instrument working as quickly as possible, while at the same time maintaining my active research efforts and channels. And begin getting ready to teach soon! And learn to be a father! So much fun! But yes, I must get things going quickly. An empty lab for a significant period of time becomes a very, very bad thing.