Adding surface LED to jewel headlight?

[ChrisVA]

Hi all,

What is a good way to add a working headlight to a brass engine with jewel installed?  See photos. I would like to make these lights functional. I'm considering:

Use pin vise to drill hole (drill bit size?) behind jewel and run magnet wire with surface mounted LED attached behind the jewel. I have no idea if this will work or what it will look like if the LED shines light "behind" the jewel?   I'll obviously also have to drill holes into the boiler and tender to run the wires through.  What techniques do you use to make these front and rear headlights operational? Do you keep the jewel in place or remove it (how?) and use acetate for the "glass"?

Thanks in advance!

 

[gmpullman]

I've never attempted class lights as most of my steam used the small Pyle style and, well, I just thought it would be an excersize in frustration, not to mention wiring the magnet wire behind the smokebox cover. I have done lighted marker lights which were somewhat larger due to the kerosine fount.

There's an article here about how one fellow did it.

Headlights are a little easier with a bit more room to work with. I coat the backside of the LED with several layers of clear PVA for insulation and to give a bit of strain relief to the solder joint.

Sometimes I'm lucky and can drill the back of the headlight and smokebox front in one operation:

PRR_N2_headlight-2 by Edmund, on Flickr

Some are thicker than others:

Q_headlight4 by Edmund, on Flickr

 

I use small glue dots (fugitive glue) which hold the LED in place but still allow adjustment so I can get the LED aimed in the best orientation in the reflector then apply a little PVA (canopy cement or Faller Expert Laser cement) which dries clear and holds the LED solidly. I have odds and ends of headlight glass handy, some from the Highliners parts and others made using various hole punches. A tiny dab of the canopy cement again will hold the cover in place.

Jewels usually have mirrored backing that would have to be scraped away in order to let light pass through. It looks like your headlight jewel is already missing and only the chromed backing remains.

Sometimes you are better off to find a replacement headlight that is already "hollowed out" for a light source. Cal Scale and Precision Scale both offer brass headlights.

Good Luck, Ed

[RR_Mel]

I went with Cal Scale Markers, 190-280.  I used 1mm 1½
volt bulbs.  I installed the markers on all of my articulated locomotives, (21).







This was years ago and I haven’t been able to locate any 1mm bulbs at an affordable price in several years.

The Cal Scale markers are somewhat fragile due to size but being careful I drilled out over 40 of them without damaging any.

Here is a link to the process on my blog.

https://melvineperry.blogspot.com/2014/10/october-26-2014-cal-scale-marker-lights.html

As for headlights I just use standard 3mm warm white LEDs.

I tried using 1mm fiber optical cable in a couple of Cal Scale Markers and it worked but not as nice as the 1mm  bulbs.

Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Turned 84 in July, aging is definitely not for wimps.

[Overmod]

What I'd do for the headlight is carefully drill the remnants of the 'jewel' out of the headlight casting and open up as much of its inside length as you safely can.  Drill as needed to get your LED to mount in the location 'in space' corresponding to where the bulb would be on the prototype.

Then make and polish a parabolic reflector out of a material like aluminum (you can chuck a piece of rod in a drill and shape it with a Dremel using appropriate cutters or hand tools as it spins, then cut off to length) that has a hole in its center either to seat on the front of the LED package or to align with a small-package LED that represents the bulb.  You can tint the reflector with something like thinned radio-dial dye (I am probably dating myself using that term) to get the 'golden glow' effect if your LED won't provide it.

Then use the technique in prior posts to make a thin clear lens and apply it, or fill the completed headlight with clear-drying or -setting material and shape or polish the lens to be flat or convex as desired.

[peahrens]

I upgraded an HO IHC pacific, including adding / relocating a Cal-Scale headlight.  I drilled out the headlight for a SMD LED lead wire, adding a MV Products headlight lens.  Per the ideas in a 2004 thread, I drilled into the back of the lens about 1/2 way and CA glued the SMD into the hole.  This loco was easy enough to thread the magnet wires back into the loco for connection.  A little tricky, but worth the effort.  Sorry I don't remember how to add a forum thread link.  I found the thread via a search:

(1) site: cs.trains.com headlight lens - Search (bing.com)

IMG_0598 (2) by Paul Ahrens, on Flickr