Modutrak Searchlight Signals (WAS: Building BeNscale Signals)

[Sokramiketes]

OK, this has been loads of fun.   Lets talk about dwarf signals.    Back about page 2 you were talking about using fiber optics with a commercial head and this LED?

Updates?   Thoughts?     I'd tried fiber optics years ago and never been too enthusiastic about doing signals that way.

None installed on the layout yet, but I played with one of the Showcase Miniature (Central Foundry) dwarf signals.  The issue with the dwarfs is that this LED is too big.  I didn't like the stock fiber optics included with the SM dwarf, but it was easy to drill out for larger fiber optic strand and now I'm happy with the appearance next to the LED signals.  I'll have to measure the fiber optics I had on hand, but am guessing the strand was .020" or .025". 

Then the idea is to leave the big LED below layout, and route the fiber optic down.  That's the next thing to try after Trainfest this weekend.

[peteski]

One issue with fiber optics is that the light emitted from the end is rather directional (you have to look straight at the end to get the maximum effect).  While that was also true for prototype or 1:1 searchlight signals, since N scale engineers don't (yet) run their trains from inside the cab, this doesn't work well for model trains.  It is better for the light to be emitted over a wider viewing angle.  My solution is to instead of polishing the end, scuff it with some fine grit sandpaper (like 600 grit).  The roughened surface will scatter the light allowing it to be viewed from a wider angle. This can also be done on a mushroomed end of the fiber (to increase the apparent diameter of the optic).

[randgust]

I'd played with fiber optic material before in the 70's with marginal success - trying to make a Bachmann crossing signal to light up, with the bulbs underneath the table.  I could get the heads bent, and mushroomed, but trying to get enough light INTO the material was another battle entirely.   Even with some pretty big bulbs, foil reflectors, etc, it still wasn't much visible unless the room lights were off.  I was battling lighting up the entire bottom of the table and getting very little light output.

I've still got a couple Showcase heads, they look nearly impossible to use though as they are so small; certainly fiber optic is it.  So to me the ultimate question isn't above the table, it's below.  Where do you get a tricolor or bicolor LED strong enough, and how do you feed it?

[Sokramiketes]

http://www.mouser.com/ProductDetail/BIVAR/SMP4-SRGY/?qs=%2fha2pyFaduiEwJaNED76BnAaw3ZxEHoa7ByeCrHmMwFsbmMvj7L0pg%3d%3d

No karma required anymore. 

Mike, Red/White in the same PLCC package (but not in stock)
http://www.mouser.com/ProductDetail/Kingbright/AAA3528QWDSURKS/?qs=sGAEpiMZZMseGfSY3csMkRKBhNdDfioel2UDuel0N6M%3d
You might want to check Digikey.
Or in stock Red/White LEDs in different SMD packages:
http://www.mouser.com/ProductDetail/Kingbright/APTB1612SURKQWDF/?qs=sGAEpiMZZMseGfSY3csMkRKBhNdDfioebGH%252bJRdT1sc%3d
http://www.mouser.com/ProductDetail/Kingbright/APB3025SURKQWDF/?qs=sGAEpiMZZMseGfSY3csMkRKBhNdDfioe44%2foBKQtLro%3d

This reply from Peteski was upthread, and had the link to the LED's I'm using.  They are certainly bright enough.  I figured I'd just drill a hole through some styrene round stock and glue it to the face of the LED.  The reflector on the LED is all white, and should send enough light into the LED...

[arbomambo]

have you seen the Showcase Miniatures 'focuser' designed for the LED and fiber optic combo?...it focuses all of the LED's light into the end of the fiber optic strand..using the techniques described in the abvce posts (mushrooming the ends, etc), I can tell you first hand, it works!
Bruce