Current Work

We are currently in full scale construction mode, working full time on building the fiber bundles. If you want to see our previous construction goals you can access them below.

Previous Construction Goals

A List of Specifications/Manuals for Items in Lab 405

This page has the documentation for the various procedures and pieces of equipment that are used in the bending tank, the splicing unit, and elsewhere in 405.

Documents for 405

LabView Program

This page details the work that has gone into the LabView program that was written to control the heaters and pumps for the bending tank in 405.

LabView Program Explanation

Temperature Measurements

This section describes the work that has gone into the construction of the thermistor for the bending tank in 405. It also has some materials devoted to describing the function and properties of a thermistor and the method used to build the one used here.

Thermistor Construction Journal

Water Tank Information

Water Tank Instructions and Diagrams

Pictures

Completed Work

Clean and organize room P405.
Hot water tank constructed - still awaiting testing
Splicing unit collars redesigned
A program was written to automatically control a heater/pump based on the temperature of the water.

Miscellaneous Fiber Testing

Alcohol Tests

Poly(methyl methacrylate), or plexiglass, was found to react to ethanol when used in high concentrations. When our fiber bending tank (made of poly) was being cleaned with pure ethanol, an obvious reaction was seen as crazing developed on the surface of the walls of the tank. Because our fibers are made from a similar material (polystyrene with flour-acrylic cladding) it seemed necessary to also test their reaction to exposure to alcohol.

The first alcohol test compared the differences between ethanol and propanol. After the first test, only ethanol concentrations were used for the alcohol tests because it will be an ethanol concentration that will be used to clean the fibers.

The procedure for the alcohol tests can be found here.

Heated Alcohol Tests

Non-heated Alcohol Tests

It was found that the fibers reacted more in heated ethanol versus non-heated ethanol. Light guide fibers which remained in 65 degree Celcius underwent significant fiber damage at lower concentrations of ethanol (around 65%) than the room temperature ethanol tests (where damage occurred around 80% ethanol). It seems as though the fiber's cladding is being disintegrated or dissolving into the ethanol concentrations they were resting in.

Epoxy Tests

To test whether the fibers could be protected from the damage from ethanol, the ends of fibers were covered with Saint Gobain's BC-600 fiber cement. The instructions for use and more information on BC-600 can be found here.

Tips on epoxy use and other test procedures can be found here.

Epoxy Tests

Strength Tests

In order to test the transverse strength of the fused bonds created with the splicing unit, fibers were fused and then broken in order to test their strength. The size of the fiber and the fused joints were measured and recorded as well as the mass that each fiber held on the fuse point before breaking.

Below is are links to the Google Spreadsheets of the raw data and graphs. It is interesting to note that, in the first test, the joints that expanded the most were also the joints that withstood the most transverse force. This may have been because the fibers that did not fuse successfully were the fibers that did not melt all of the way, and consequently did not fill up any extra space that may have been in the glass ferrule.

The expanded joints in the second test did NOT turn out to be good indicators of bond strength as I had previously thought.

Strength Test 1 (Completed April 4, 2013)

Strength Test 2 (Completed April 12, 2013)

Ferrule Measurements

In hopes of understanding the bulge in the spliced region of the fibers, the ferrules they are spliced in were photographed under a microscope and measured using a tracker program that allows for in-photo calibration and measurement. The ferrules were placed as perpendicular to the table as possible in order to get the most flat, head on shot of the ferrules. The error in the measurement of the angles was quite high. Moving the compass only a little bit (in the tracker program) lead to very different degrees read. Because of this I would estimate the angle to be off anywhere from +- 1-2 degrees. I would say that the lengths measured have an error on the order of +- .05-.1 mm

Measurement Photographs

New Ferrule Measurement Photographs

Quality Control Procedures

Fiber transmission measurements were carried out in Lab 402 using a flash ADC and a VME-based data acquisition system that was loaned to UConn by Jefferson Lab. Our contact at Jlab for this system is Alex Somov. Setup and operation of the CODA data acquisition platform is described here.