I'm adding an oscillating Mars headlight to an Atlas GP7. The double light housing in HO from Details Associates is plastic. The top light would be clear and the bottom, red (rarely used except when the train goes into emergency). I have several options, though some say that a bulb provides a more realistic oscillation than an LED. I also have some MV headlight lenses. Here is what I see as options:
1.00 Use small surface mounted LEDs which I have and mount them behind the MV Lenses with the foil partially scrathed off the back of the MV lenses.
2.00 Use a bulb with a bulb holder inside the unit and clear plastic rods to transmit the light to the inside edge of the MV lenses similar to how the Atlas unit is equipped. Note that the distance btw the two headlight centers in the Mars housing is wider than the two beams for the Atlas unit provided, so at least one hole would have to be filled and redrilled.
3.00 Use small clear and red LEDs that may have to be turned down to fit in the Mars housing but with a rounded front to simulate the headlights.
Of course, the same tecniques can be used for the Pyle twin beam headlight that is below the Mars housing.
I am looking for information from those who have done this sucessfully.
Here is the link for a photo of what I'm talking about. The Mars light is circled. The standard Pyle housing is below it.
http://s1380.photobucket.com/user/Vic244/library/?sort=3&page=1
wabash28001.00 Use small surface mounted LEDs which I have and mount them behind the MV Lenses with the foil partially scrathed off the back of the MV lenses.
That's how I do lights like this now. The SMD LED makes things much easier, saving a lot of hacking and preserving the original apperance if you use a little care. I also use the MV lens trick on headlights and backup lights, where it's big enough to look really good, esepcially if you add plenty of resistance to tone down the LED's light output.
I'm not quite sure if you're planning for the Pyle right now or not, but with the two fixtures you'll need to use two functions. At least that's how my NCE's are. Very similar to how ditch lights are done, except the lights are much closer together and the timing in the circuit is done differently to simulate a signal light like a Pyle that uses twin beams.
BTW, at least with the NCE decoders, I've found the simulation of these lights works really good, don't miss bulbs at all. YMMV
Mike Lehman
Urbana, IL
With Mike's help and advice, I too used surface mount LEDs on an Athearn F7 application.
I ruled out bulbs as unreliable, prone to burn out, and too large for many applications, and they create heat so the plastic housing is at risk.
Surface mount LEDs are capable of creating highly realistic lighting effects, and they are extremely small which is crucial for applications like the one that you are considering.
One word of advice regarding surface mount LEDs. They can be extremely bright so experiment with different resistors to get it right. You may need some pretty high values on those resistors.
Rich
Alton Junction
I have ordered some of these to experiment with:
http://www.moreleds.com/icecube.htm
Take Care!
Frank
Edit: I probably should have stated, that those are the one's I ordered to experiment with, there are smaller 2mm LED's for headlights and such, if you navigate the site they have many LED's in smaller sizes, with wiring diagrams and with resistors. 1.8mm for Headlights:
http://www.moreleds.com/headlights.htm
A 3mm cube may be too big for your application.
Here is a link to Ulrich Models and the surface mount LED.
http://www.ulrichmodels.biz/servlet/the-350/Minature-Surface-Mount-LEDs/Detail
The people at Ulrich Models specialize in these miniature LEDs and welcome phone calls to discuss your application. Give them a call.
Thanks for all the replies. I know that all the methods will be functional but my biggest concern is if the oscillation will be optimal. Like I said, I've heard some rumbling that a mini bulb provides the best osciallation. Mike, yes, I'll have a seperate function for the standard Pyle headlight below the Mars light. I've got another after market part from Detail Assoicates for that. From interviewing Wabash railroaders and viewing video footage, the Mars lights wasn't used as much as you would think but more often on passenger trains. Some train crews did not like them. And incidentally, if I can pull it off, I'm going to have another function for the red Mars light.
Victor Baird
www.erstwhilepublications.com
zstripeEdit: I probably should have stated, that those are the one's I ordered to experiment with, there are smaller 2mm LED's for headlights and such, if you navigate the site they have many LED's in smaller sizes, with wiring diagrams and with resistors. 1.8mm for Headlights: http://www.moreleds.com/headlights.htm
Wow - those guys are making a killing on those LEDs ! - A dollar EACH ! I've gotten the same thing off ebay in quantities of 100 for well under $10 and free shipping !
Big bucks in repackaging and catering to a specific market.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Mark,
I went through the same thing, when I picked up a couple rolls of the warm white 300 SMD's, some were asking 49.99 per roll, I got them for 34.99 a roll, from E-bay.
I am going to have to do the same thing. But since I am doing this in Z, I will have to make the Mars light housings from scratch and also make new headlight housings, for the CB&Q GP7s I have. I was thinking the same about the red lens, I really dont need it. I will also have to find a different dcc board, than the one that just pops in, as I will need more functions. First thing is to find the dimentions for the Mars light housing.
I use MV lenses almost exclusively on my locos. I have found that instead of scraping the foil off, if you use a small drill and drill about 1/4 the way thru the lenses, the lighting effect provided by the lenses is real close to what a real HL or Mars looks.
Placing a SMD LED, behind the hole, attached to the lens, and then sealed so there are no light leaks works the best. The light actually comes out from the lens and does project down the track better. I've done this with medium to large lenses, and am very pleased with my loco lighting.
I admit that I haven't tried this on some of the smaller diesel lens but I will be soon. I'm thinking about using a fiber optic "plug" to insert into the hole drilled into the lens and placing the smd behind that, buried inside the body.
Carey
Keep it between the Rails
Alabama Central Homepage
Nara member #128
NMRA &SER Life member
wabash2800Mike, yes, I'll have a seperate function for the standard Pyle headlight below the Mars light.
Victor,
Yeah, in this case, you may need 3 functions. One for the standard headlight. Then, if the Mars light has two lens/lights/LEDs, you'd need 2 more functions, one for each, if you want to get the best effect possible. I've done this several times.
However, I have taken to using a single 3 mm LED behind most of my dual lens Mars or Pyle lights. In HO, it's big enough to get good light from both of the "lamps" in the housing and, with the NCE decoder effects at least, does nearly as good a job as the 2-LED versions. And the single LED is much easier to install.
cjcrescentI use MV lenses almost exclusively on my locos. I have found that instead of scraping the foil off, if you use a small drill and drill about 1/4 the way thru the lenses, the lighting effect provided by the lenses is real close to what a real HL or Mars looks.
Carey,
Good point. I've used the drill method also and it is very realistic with steam-era headlights.
With MV lenses, some caution is needed because they are actually a little "soft" and drilling can distort them if not done carefully and gently. Another method that works and requires similar care is to sand off the backing in the middle by gently pushing them on fine sandpaper or file.
Folks, thanks for your input. I'm going to take the plunge for the Mars light and the dual Pyle lights on the front and back of the model. I have surface mounted LEDs with lead wires already attached plus resisters, all from Richmond Controls. Drilling out the Detail Associates housings and deliclately removing the old detail on the shell behind where the Mars light will be and adding a new Pyle housing below that will be necessary. Hopefully, I'll have the right sizes of MV lenses. They are very diffucult to find in stock anywhere! I will drill the MV lenses rather than scratch away the foil. This will also be my first DCC installation (with a Soundtrax decoder). And, I'm going to have to match up paint for touchup! I suppose I should use some shrink tubing for the small leads from the LEDs? The disadvantage I see of gluing (with canapy glue) the LEDS to the headlights housings on the shell is how to remove the shell. I suppose I'll have to add plenty of extra length for wiring....
Those surface mount LEDs with insulated 6" lead wires from Richmond Controls are terrific.
Let us know how it turns out.
wabash2800I suppose I should use some shrink tubing for the small leads from the LEDs? The disadvantage I see of gluing (with canapy glue) the LEDS to the headlights housings on the shell is how to remove the shell. I suppose I'll have to add plenty of extra length for wiring....
For the Richmond Controls SMD LEDS I generally use black "liquid electrical tape". It also works great for blocking light leaks in odd spots.
To fix the SMD LEDs in their housings, I generally use canopy glue. If there is a lengthy run of the magnet wire, I'll often slip them inside a piece of shrink, BUT I don't actually shrink it. This allows for later maintenance, while keeping them from tangling.
Be cautious on making really long leads. You've got to stick everything back under the shell with a rotating driveline in it.
What I have found that works well for me....is similar to what Mike does. But at the inside top of the shell I use double sided tape to keep the long wires out of the way of moving parts from tangling and hanging down.