This is the R2 assembly fixture at ODU. The R2 frame or cart is sitting on the floor around the fixture.
The adjustable gantry crane straddles the fixture. The frame or cart rests on 4 low profile scissor jacks
with rollers mounted on the jack base. Using 4 jacks, all on rollers, the frame could be easily positioned.
The frame or cart must be attached to the detector box without introducing any stress or stain.
Here you can better see the survey pads used to define the planes that the R2 endplade would lay in.
Larry Weinstein and Brian Raue can be seen in the background.
Here you can see one of the anodized aluminum pad the R2 end plates rest on. The aluminum had to be anodized
so it would not rub off on the stecilite endplade.
The detector is shaped like an orange section. The fixture determined endplade positions relative to each other.
Here you can see the entire fixture along with the gantry crane just after the detector frame or cart was lowered over it.
Each endplade was lifted at the approximate angle and placed onto the fixture.
The outside endplade had to be placed first due to height limitations. Here you can see the clamping devices
used to press the end plates onto the alignment pads. The end plates deflected due to their own weight
Clean nitrile gloves had to be worn because the components were already clean.
The nose plate and back plate attached the end plates together and fixed the separation at those locations.
Aluminum posts and diagonal struts were installed and formed a removable frame to hold the wire tensions.
There was alot of flex in the clamps due to the design. Nylon pads were pressed against the endplade to
flatten them out. Several iterations were required.
The endplade had to be solid on the alignment pads before installing the posts and struts.
Much of the back plate had to be cut out to permit R1 to fit into the CLAS bore with R2 already in place.
Each post was a different length solid aluminum rod with. One end was threaded for a quick release socket
while the other end had a through hole with a slot. The length was adjusted using a treaded rod and nut.
The a pinch clamp locked the rod in place.
The frame was adjusted and attached to the detector box aluminum pin and hinge brackets.
Once complete, wheels were attached to the frame and the box was covered with clean paper until it went into the clean room.
Each box assembly was surveyed prior to removal from the fixture.
Here you can see the alignment plated, the adjustable side of the posts, and the diagonal strut attachment.
Along with losing much of the back plate, many wires were also lost along with the last post and strut.
The clamps had to be removed and the frame raised above the alignment fixture in order to survey the detector frame
in it's final state.
The survey group made the trip to ODU at least 7 times. First to align the fixture and then for each of the six sectors.
You can see Kelly in the foreground of this pic.
Due to the low hook height and detector dimensions, a pair of spreader bars had to be used to lift the assembly
off of the alignment fixture. The gantry crane had to be rotated at an angle such that the nose of the detector
was able to lift up above the bottom of the gantry beam in order for the frame or cart to clear the alignment fixture.
The gantry with the detector assembly was then rolled to the other end of the room where the wheels could be attached.
Once clear of the assembly fixture, the detector couild be lowwered and rotated.
The detector is also taken into the clean room using the same method.
People power is the motive force for moving.
The detector assembly would remain on the frame of cart until it was attached to the torus.
The spreader bars and frame used 3/8 inch forged lifting swivels.
Moving day was an all hands event as both eyes and muscle were required in many locations.