can fiber optic cables be repaired

[Brett]

Hey folks,

can broken/cut fiber optic cables to the indicators on top of 71 Fenders be repaired or mended? If not, what exactly needs to be found used to replace the broken parts and where does it connect?

Thanks in advance

[The Tassie Devil(le)]

G'day Brett,

As far as I know, the answer in simple terms is no.

BUT, talk to anyone in the Telecommunications Industry, and they should be able to guide you to a means of joining it, as a lot of Telecommunications is done with Fibre Optics.

But I would say that the cost of the joiner would probably be more than you whole car is worth to do it properly.

Having said the above, the simple solution would be to simply trim the ends exactly square, then carefully butt the ends together and  wrap tightly with black tape so that no light can get in, or out, and that should be sufficient for the needs of the car.

Bruce Reynolds,
The Tassie Devil(le),
'60 CDV,
CLC# 18992

[Joe Manna]

Hi BRETT, HOW ARE YOU?I HAD JUST ORDERED A NEW TL CABLE FOR MY 91.THROUGH THE LOCAL DEALER.I TRIED TAPING MINE AND IT DID NOT WORK.BUT KEEP ME POSTED ON YOUR SITUATION.THANKS JOE

[Wayne Womble 12210]

Use a sharp new razor blade and make a clean straight cut.  Butt the cable together and use a thick heat shrink of the proper size to hold the cable together. You could use two or more layers to stiffen the jount.

[Mike]

Hey folks,

can broken/cut fiber optic cables to the indicators on top of 71 Fenders be repaired or mended? If not, what exactly needs to be found used to replace the broken parts and where does it connect?

Thanks in advance

Brett:
I have tried various way to repair these cables with no success.  There are hundreds of
strands of fiberglass in each cable, and making them meet up again is about impossible.

My suggestion is to contact a qualified parts dealer to sell you a replacement -- even from
a junkyard as they don't go bad.  As to how they connect -- the fiber optic cable has a plug
on the bulb fixture that feeds to the lamp monitor on the fender top.  If you follow
the wire -- you'll see that.

HTH, Mike

[Dennis DiNorcia]

I ordered new fiber optic cables for my Eldorado from my Cadillac dealer. I ordered it for my 1989 DeVille and ordered the ones used for the taillights since these were the longest on the car. On the exsisting cable end there is a usually a brass bushing that keeps the cable from coming out of the attaching cap. I used the bushing from my old ones. I got it off by inserting an awl into the opening and spread it open until the old cable came out. I then inserted it onto the new cable (don't forget the en cap first) then carefully crimped it to stay on. After this was done and attached, with a little cleaning of the lenses on the lamp monotors, they were perfectly ne. I hope this helps.

[Don Collier]

     I repaired some damaged (crushed) cable and spliced some breaks on my 76 Eldorado with the supplies (cables, splicers, connectors, etc.) from these folks:

www.fiberopticproducts.com

    
     Was much cheaper and easier to repair the few breaks in the rear rather than trying to pull new cable without damaging it. I do recommend getting their "cutter" tool.  I work with Fiber Optics in the IT field and it is absolutely imperative that the cuts be perfectly square and "sheared" so that the fibers aren't crushed / fractured on their ends and that the ends meet perfectly.  Each cable has multiple strands and the more strands that have crushed ends, the less light there is transmitted.

[Mike Josephic CLC #3877]

     I repaired some damaged (crushed) cable and spliced some breaks on my 76 Eldorado with the supplies (cables, splicers, connectors, etc.) from these folks:

www.fiberopticproducts.com

     Was much cheaper and easier to repair the few breaks in the rear rather than trying to pull new cable without damaging it. I do recommend getting their "cutter" tool.  I work with Fiber Optics in the IT field and it is absolutely imperative that the cuts be perfectly square and "sheared" so that the fibers aren't crushed / fractured on their ends and that the ends meet perfectly.  Each cable has multiple strands and the more strands that have crushed ends, the less light there is transmitted.

Don:

Just for my own info & understanding, you mention a tool that can make an even cut.
However, how do you get the two cut ends together again so that the cable matches
up with all the hundreds of fibers?

Any info would be very interesting to know.

Mike

[The Tassie Devil(le)]

As far as I see it, it isn't a problem with having to "match" up individual fibres, but simply getting the fibres as close together as possible, so that the light coming down one fibre can simply "bounce" across the minimal gap to another one and keep on going till the end.

Granted, there will be some "light transferrance" lost, but in the case of a "light minder" which it all that the system is, and not an intricate communications device, then, if 50% of the "signals" get through, it will still show an illumination at the other end.

Bruce.

[Don Collier]

Bruce is onto it...  You don't have to match up the individual fibers, but, you do need to have a smooth, "shearing" cut and you want to minimize the air gap for the light to jump (think microns, not, "just" close :-)).

If you look at how things "cut" you'll see what I mean.  Look around your shop...see the wire cutters?  Look closely at the "edge" and you'll see that the working edge is "V" shaped.  If you cut a wire with them, look at both ends of the wire you cut.  You'll see both have suffered a "crushing" of the wire.  No problem with wire, but, if you crush the ends of a light tube, you diffract the light leaving the tube (it has to bounce around the broken pieces).  Now look at your good chisels, not your junk ones, but, your good mortising chisels.  Very gentle angle, perfectly flat back.  Now, push it against a protruding defect in a piece of wood.  The shaved off piece is fractured, from the curling induced by the angle, but, the "flat" side leaves a smooth surface - applied to fiber optics, all of the crushing is transferred to one side of the cut leaving the other side "smooth".  Two smooth surfaces pressed closely together - minimal diffraction.

Now for the holding them together...special fiber optic butt connectors.  These are similar to electrical butt splice connectors, but, designed to hold the fiber optic cable firmly without crushing.  They are also designed to be more rigid than heat shrink tubing - remember the air gap issue...diffusion - the other enemy.  You want to firmly, without crushing, hold the cut ends as closely as possible together with the smallest air gap you can get.  Minimal diffusion :-)

I repaired all but one of the cables and when I was done, the lone good one was just a tad brighter than the others.  Not a big deal, but, it annoyed me.  I cut the good one, spliced it back together.  Now they are all the same...you can't tell from factory 

[Mike Josephic CLC #3877]

Thanks, Don.  This is the info I wanted in order to understand how these
were done.  Your explanation was very good and understandable.
I didn't know they made special connectors for repairs. 
I don't have any broken right now -- but always willing to learn something new.

Mike

[Don Collier]

You are quite welcome 
I always strive to learn something new every day...one cannot live long enough to know too much 
Unfortunately, at my age, I think I forget 3 things for every new one...  
Or so my wife would lead me to believe 

[AFI]

Don't know about fiber optic repairs, I kind of doubt it. But, I do have 6 #12009247 monolite fiber optic cables for Cadillac.
It was a headlight monitoring system used in the 70's and 80's. I had a couple Sevilles, '76, '77, '80 that had the system.
So. Let me know if you're interested in them. I can take a photo of one and send it to you for correct application.

[cadillacman]

Hi all,

BMW do sell a repair kit for the fibre optic cables but you need special splicers to cut the cable.
Hit google this will show you the kits I hope this helps.

Good luck, if you are stuck PM me and I will ask at work tomorrow for the part number for the part number and methods

[TJ Hopland]

Please note this thread is from 2007.   

[The Tassie Devil(le)]

This thread may be old, but at the moment I am constructing a joiner so that I can repair the rear Fibre Optics in my '72 Eldo Convertible.

As soon as I have the completed article, with pictures, I will post it.

Bruce.

[TJ Hopland]

After 13 years it better be a good write up.   Long term review?

I fixed one several years ago and it worked as long as I had the car which was 3 or 4 years.   I have no idea how well it worked before the damage and fix because it was broken when I got the car.   It was the one for the thermometer in the mirror where the bulb is under the dash.   I used a cable cutter that has the c shaped jaws to cut it then shrink tubing to hold it together.