BW Fiber Fusing

New Procedure

I can try using the microscope to determine which end of a sci-fi to fuse. If the microscope does not work well, I can request a magnifying glass. The magnifying glass goes in the box on the soldering table when we are done with it.

I should use the weights to test some of the real fuses I am doing (every nth fiber) with 850 g weights. I don't need to do practice fuses if my real ones are going well.

5/14/2018

Apparently the weight testing needs to be done differently. The 100 gram weight with the hook or the 50 gram hanger should go on the fiber, but there is a problem with the hooked 500 gram weight. That should not go on the fiber.

There is also a new way to fuse. I should press the fibers together while holding down the top ferrule with both hands to add pressure and prevent wings.

I need to adjust the focus of the lamp to prevent fiber material from burning away, which is happening now. Jim said the lamp would probably have to be a little lower and maybe closer to the ferrules.

The Heat dial adjusts how long the lamp is on. It has been usually set at 3.

To prevent the ferrules from slamming together, we can leave them closed or close together so that if someone accidentally hits the start button they will not have room to build up speed. We could also put some sponge gasket between the metal parts to the left of the ferrules as a cushion.

I wanted to increase the minimum pressure in the compressor, so I looked for the setting screws to do that. I am not sure, but it could be the tall black one that seems to have a plastic head. I gave it about two turns counterclockwise.

5/15/2018

I should ask a question if anything seems wrong with the splicing unit. I did not recognize that the ferrules should not slam together, but that would have been a good time to ask whether they should be slamming.

I also did not realize that the splicing unit was not giving any horizontal pressure to the fibers.

To recognize problems like slamming or lack of force from the machine, I need to think outside the box, or in other words think creatively about the fibers. Following a set procedure is not enough because the procedure may not be good enough.

Jim said one problem with the splicing unit was that originally it was for smaller fibers that did not need as much pressure to be fused. The fibers we are using require much higher pressure, and the splicing unit does not work as well with higher pressure.

5/16/2018

I never need to turn off the compressor except if I have to adjust the pressure spread or maximum settings.

I need to test the splicing unit before operating it every day. I should put sponge gasket and a scrap fiber between the metal pieces that hold the light guide and press start so that if something is wrong and the ferrules are about to slam together they won’t come in contact. They should meet gently rather than slamming together.

I should blow a gentle stream of canned air to clean the fibers rather than a strong burst. I need to remember to aim away from the ferrules though so I don't blow dust on them. To clean the ferrules I can also use a gentle stream.

When I weight test fibers, the fuse site should be centered between the supports, midway between them.

5/18/18

The compressor regulator should always be set to 89 PSI. I should not turn it to zero before leaving at the end of the day. I should instead disconnect the hose that connects to the regulator. I should also drain the compressor tank every day, but I don’t need to turn off the compressor to do that.

Jim said some of my fuses would be acceptable for the real fibers but they should be better. I will need more practice.

Fusing fibers three or more times increases the amount of cladding included in the fuse, so there is a downside to repeating a fuse.

5/22/18

For some reason I am suddenly getting incomplete fuses unless I push hard again.

Maybe it's just that the parts that grip the long fiber and push it to the right are going all the way to the right sometimes. Maybe if I watch and notice that happening I should push hard but if the grips have not gone all the way yet I should push gently.

5/23/18

In fusing practice, I found that if the grippers don't move all the way right, I can let go of the long fiber and let the splicing unit do all the work, at least until they do reach the stopping point where they can't go any farther.

If the grippers do move all the way to the right, I have to push fairly hard but less than I used to. When there is no horizontal pressure from the splicer, I have to push on the second fuse as well as the first. If I don't push on the second fuse, it will go from an almost complete fuse to a very incomplete one.

I noticed some strange results in fused fibers today. It looks like cladding might be boiling away, but it is not on the side I would expect.

I will fuse some fibers and label them. Two will be fused just once with the bend pointing up and back toward the windows, and two will be fused twice, first with the bend up and back and next with the bend in front and down.

5/25/18

Yesterday Jim said my fusing problems may be because I adjusted the set screws for the valves leading to the spaces above and below the piston in the fusing unit. I adjusted them because I thought the ferrules would have come together too hard without an adjustment.

Jim thought that the top ferrule was moving down too quickly because I had the pressure from the regulator set too high. Maybe if I had just lowered that, I would not have needed to adjust those set screws. However, the pressure is a little above 40 PSI now and the descent and ascent speeds depend on where the set screws are set.

I noticed that when the ferrules are supposed to be clamped together I can still easily raise the top one. Yesterday I thought I had figured it out. I thought the downward pressure increased after the horizontal pressure was applied. I thought that might be why the top ferrule descended slowly. Today I am not sure because the top ferrule still goes up fairly easily after the horizontal pressure begins. It increases as it is moved higher, but when you first push it up it moves easily. That makes sense because moving the ferrule up means you compress the air above the piston and increase the downward force. I am not sure that the pressure is really 40 PSI when the ferrules are together. I don't have to push up with 40 pounds to move the ferrule up.

But force = pressure * area. If the area is small, the downward force would also be small even though it is 40 PSI. With an area of 1 square inch, there would be a force of 40 pounds. If it's 1/10 of a square inch, it would be only 4 pounds.

I checked the downward force just after the light turns on, and it increases then. It is not when the horizontal pressure is applied but when the light turns on that that downward force increases. I can still push the top ferrule up a little but it is more difficult when the light is on.

I should not adjust any setting of the splicer. If there is something wrong, I should tell Dr. Jones and Jim. The regulators should be 35 PSI on the left and 40 PSI on the right. If they are more than 5 PSI off, there is a problem but I should not adjust them. If the grippers move all the way to the right, I should stop the fusing as long as the light has not turned on. If the light has already turned on, the fibers will be damaged and I should stop fusing any more fibers.

5/30/18 I found the website for the air compressor we will use for fiber cleaning. It is a Campbell Hausfeld FP202801 compressor. I also found a product manual for the compressor.

Jim made more marks to show when the grippers are bottoming out to the right.

Sometimes there are lips at the end of a fiber. They usually look like white lines, maybe where the cladding has flared. Today we found that when there are lips at the end of a fiber, they can cause an incomplete fuse.

I should try to fuse the fiber ends that do not have lips.

Jim used a laser to check whether light was scattering from a fiber after wings were removed. We did not see much scattering from that fiber.

6/4/18

I realized today that if a wing forms during the first fuse, one will also form during the second fuse because the first wing keeps the ferrules from meeting properly.

6/7/18 Dr. Jones said we have been too focused on getting strong fibers. We need ones that will transmit light.

I should push but not as hard or as long as I have been doing. As soon as the clamps start moving to the right, I should let go but not pull the fiber back. The thinking is that the light turns on first and then as soon as I see the clamps move I let go.

6/13/18

Jim said that the razor blades come with oil on them, which is bad for the fibers, ferrules, and splicing unit. We need to remove the oil before using them to remove wings.

To remove the oil, we should wash the blades with soap and water, then follow up with ethanol. They should then be dried and clean before use.

6/18/18

Some of the light guides are too narrow and the clamps start moving before the light turns on. For those fibers I should try putting a little paper or piece of lint-free cloth on the bottom gripping clamp. It should not get between the clamps because then it would keep the ferrules apart. It should be at the end of the clamps farthest from the ferrules so that if it does keep the clamps from closing completely maybe the ferrules will still be in sufficient contact.

Today I tried paper and lint-free cloth as methods of enhancing the grip of the ferrules on the fibers. I tried a small strip of paper, a larger piece folded into a v shape, a large piece wrapped around the long fiber, a small strip of lint-free cloth, and a larger strip of lint-free cloth that would have extended between the clamp surfaces that are supposed to be in contact.

The paper wrapped around the fiber prevented the clamps from moving at all except when I pushed hard enough to make them move suddenly. Sudden motion is not acceptable. The clamps should move steadily and gradually as the heating light is on. With the paper I got fuses that broke at 850 grams. When I switched to lint-free cloth, some of the fuses held 850 grams. However, the clamps still moved to the right spontaneously during some fusing attempts.

Today Andrew and I tried removing lips from some fibers. He used 1000 grit and I used 5 micron grit. I fused some of mine and weight tested them. Two broke at 850 and one broke at 1000.

Even with 5 micron grit it is easy to remove some of the core while removing a lip. 1 micron grit and copier paper don't seem very effective, though.

6/20/2018

If the clamps seem to be moving too fast, I sometimes push the top ferrule and clamp down to try to slow the clamps. Sometimes this seems to work. I am not sure if it is better just to let the clamps move or to slow them down that way.

I want to find a better way to remove lips. The problem is that, as with polishing, the fibers may not be aligned correctly as we use sandpaper. They easily tilt as they slide across the paper.

7/13/2018

Jim said today that we should try to avoid wings. If the sponge gasket is too thick, we might try electrical tape to prevent the clamps from bottoming out while fusing thin fibers.

He was concerned that if the light guides hang off the table during fusing, they could twist and cause problems. We could clamp a wide board to the table so the fibers will not hang off during fusing. We should put the black cloth from the dark box over the board, and even without a board we should cover the the area with the cloth. However, we will need to avoid snagging the end of the fiber on the cloth and possibly damaging the cladding.

Jim looked at one of my fuses from yesterday. He noticed that the line around the fuse site was faint on two sides but more pronounced on the other two. He said the fuse was incomplete somewhere, maybe at a corner. That may have been because some cladding was missing from one of the fibers. I am not sure whether he said the fuse was incomplete only at the cladding level or if some of the core was not fused either.