I have never used fiber optics but I recently saw a module at a train show that used fiber optics to add life to a scene with a grass fire. Sparked my interest in how I might use fiber optins in my own layout.
My first step was to start researching on how it was done. Turns out that it is actually a simple concept even though implementing it may be a challange. My first attempt will be to add exterior lighting to an industrial area such as a refinery. If you have ever seen one at night, they have a mirad of external lights scattered around the structure. I model in N scale so decided a long time ago that LED's would not give me the effect I wanted. However, the tiny lights that fiber optics can produce should give me the effects I want.
I am looking for guidance. I have already ordered a sample kit from The Fiber Optic Store so I will have some fiber to experiement with. In the meantime, I would like any comments on the following that you can offer.
1) Who has done something similar by adding lights to the exterior of an industrial structure? Pictures?
2) What fiber size would be prefered for external light in N scale?
3) Suggestions on how to route the fiber through an open structure? Lots of my structures have external open frameworks such as catwalks, towers, piping, etc with no hidden structure to easily conceal fiber.
4) Suggestions on how to terminate a fiber to get it it shine like a light bulb? Don't need it to light the scene but I want it to look like an exterior light bulb as seen from a distance.
5) Any good source (book, web site, etc) with "how to" info?
Paul D
N scale Washita and Santa Fe RailroadSouthern Oklahoma circa late 70's
PED 4) Suggestions on how to terminate a fiber to get it it shine like a light bulb? Don't need it to light the scene but I want it to look like an exterior light bulb as seen from a distance.
I suggest sanding the end of the fiber with fine sandpaper. Not just the end itself, but also the last fraction of an inch. Cheap experiment. I predict that fraction of an inch will glow like a bulb.
Now, this will make an awfully long lightbulb (but maybe a great fluorescent tube?). To make the glowing part lightbulb size, you need to paint or cover the rest of the fiber, which you were probably planning on anyway.
Fiber doesn't do sharp corners well, so "concealing" it in the open is going to be a challenge.
Still, this sounds like a very interesting idea. I look forward to hearing of your progress!
Ed
PED4) Suggestions on how to terminate a fiber to get it it shine like a light bulb? Don't need it to light the scene but I want it to look like an exterior light bulb as seen from a distance.
The easiest way to get fiber optic cable to look like a light bulb is to apply a bit of heat to the end of the fiber with a lighter or a hot soldering iron. Don't touch the fiber. Just hold the heat source close. The plastic will form a small mushroom shaped 'blob' (for lack of a better word). You can make it bigger or smaller depending on how much heat you apply. In your case I think that you want minimum flare.
Actually for N scale, I don't think you need to do anything to the visible tip of the cable. Cut it with a sharp blade and that's it. You will get plenty of light. Nobody will be able to see the shape.
The other end of the fiber will end up in a bundle. How many fibers you can fit into a bundle varies, but basically you want every fiber pointing directly at the light source. I glue the bundles together with epoxy and then cut them off square. I then use epoxy to glue the light source to the bundle, and then cover the joint with heat shrink tubing. Note that I use LEDs so I'm not worried about life expectancy. If you are using incandescent bulbs I would not glue them to the bundle. That will make replacement a PITA.
PED3) Suggestions on how to route the fiber through an open structure? Lots of my structures have external open frameworks such as catwalks, towers, piping, etc with no hidden structure to easily conceal fiber.
That will be a challenge. The finer the fiber optic cable you use the easier it will be to bend it, but you will never get a sharp bend. I used fiber optic cable with a very small flare in this HO cab to illuminate the roof lights. The LED is in the chassis. The head lights and signal lights are also fiber optic cable that has been flared as I suggested above. The photo doesn't really show how bright the roof lights are:
Personally I wouldn't worry about having the fibers visible. There is lots of conduit attached to that sort of structure in real life. Disguise the fibers as conduit by painting them. Getting the fibers to lay perfectly straight might be the biggest challenge. If you install support bars every so often like the real stuff has, you should be able to attach it at one end and then pull the fiber straight and hold it while you glue it in place. However, before using CA to glue the fibers, I would do a little test to make sure it doesn't damage the fiber.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Great info.
- I am suprised at the suggestion to use CA. All the web info I have seen so far indicates that the CA will damage the plastic fiber. Typically suggests a glue that is plastic safe.
- I think the suggestion to disguise the fiber as painted conduit in open structure is a great idea.
- I realize that the bending limits of the fiber will be a tough challange but I think I can work within the limits.
- The Fiber Optics store sells individual strands of fiber as well as bundles. I think they sell a 32 strand bundle. That should allow me to use a single white LED on one end then distribute the 32 strands throughout a structure to add a lot of pinpoint lights.
- Will need to experiment with the finish effect on the ends. Some ends will be viewed from the side while others from the end. Different views may require a different end treatment.
More comments?
Usually if Mel says it works, it works. The concerns I see on the webs are making the fibers brittle and melting. Mel is using it at the end on the LED. A little melting wouldn't be terrible and there shouldn't be a lot of flexing going on at the point anyway.
I use the same silicon caulk for track, where I have an LED and a light pipe serving as a loco headlight.
Henry
COB Potomac & Northern
Shenandoah Valley
Epoxy will work nicely for glueing fiber.
Received my sample pack of fiber and it included 2 samples of multi fiber cable. How do I remove some of the outer cover without damage to the internal fiber strands? I have a coax cable stripper as well as a Cat5 cable cover stripper. I know they can be used to remove the cover on the fiber bundle but I am concerned that it would damage the internal fibes that are close to the outer cover.
These bundles look like a great way to add many points of light to a structure so I expect to be using some of this in lieu of trying to build a bundle from individual strands.
PED Received my sample pack of fiber and it included 2 samples of multi fiber cable. How do I remove some of the outer cover without damage to the internal fiber strands? I have a coax cable stripper as well as a Cat5 cable cover stripper. I know they can be used to remove the cover on the fiber bundle but I am concerned that it would damage the internal fibes that are close to the outer cover. These bundles look like a great way to add many points of light to a structure so I expect to be using some of this in lieu of trying to build a bundle from individual strands.
If you want to use cables like this, I suggest you strip back the outer sheath with any tool you care to us (such as your coax cable stripper). After that's done, any fibers that are (significantly) damaged will not conduct light. Just fold them back, or cut them off, and don't use them.
There should be plenty of usable fibers left.
Ed - That is where I was headed but I wanted to see if there was a way to do it with no damaged fibers. The bundle has more strands per bundle than I would ever use in a single application.