My first brass steamer to DCC: Thoughts and musings => Photos added

[tstage]

Here's a few photos of the installed 0603 SMD LEDs and connections: (Click photo to enlarge)

[wrench567]

Nice Tom.

Planning is paramount to a successful install. I have done 5 for myself and several members of my former club totaling around 20. Most have been sound and a few non sound. Some with can motors and a good portion with modified open frame motors.

 Most of my installations have been in the tender. I use the TCS 6 wire JST connector from locomotive to tender. I have one 0-6-0 that has a micro sound decoder under the motor because the speaker took up all the room in the tender.

  I would love to see what you have done for the connection between locomotive and tender.

  Have fun and stay safe.

        Pete.

[RR_Mel]

Tom

Pictures, pictures please.

I too run higher resistance with my LEDs.  I rarely run them over a couple of ma.  Much closer to incandescent lighting.  The warm white 603s and 1206 LEDs still look bright at 2ma.

I use wide angle dispersion 3mm warm white LEDs in my passenger cars, most well under 1ma each.  6 to 8 wide angle LEDs spaced at 1” gives uniform well lit interiors.





Total current for this car 2ma at 4 volts, 4 table lamps and 6 over head wide angle LEDs.

I use the tiny round header connectors in all my passenger cars and a 2K trim pot to adjust the lighting level between 2ma and 4ma.


I still use #36 Litz wire for my micro LEDs, I’m to shaky to install magnet wire without dinging the paint insulation.  On occasion I even ding the Teflon insulation on the Litz wire.  The tiny wire doesn’t last long under a short.  They let off smoke and I haven’t been successful putting the smoke back in the wire, I replace the chard wire.

I bought some ⅛ watt at 2.5KΩ gaps from 1KΩ to 36K specifically for the micro LEDs, the smaller size gets them into tighter places.  A 10KΩ resistor in series with a warm white LED draws a whopping .008 watts.


Mel



 
My Model Railroad  
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 

[hon30critter]

Hi Tom,

Congratulations on your successful brass engine decoder installation!

I agree that using higher value resistors for steam era headlights is a great idea. Using a 20k resistor would work very nicely based on my (limited) experience with LEDs. I used 30k resistors to get a nice glow reminiscent of early 20th century electric lamps for the interior lights in my McKeen Motor Car.

Dave

[tstage]

I just completed converting my first brass steamer to DCC: An Alco Models NYC M-1 0-10-0 switcher.  Along with isolating the motor, I also installed front & rear headlights using 0603 "warm white" SMD LEDs and 34 AWG magnet wire.  To make the connections between the locomotive and tender for the rear headlight, I used individual female round headers, which are smaller than regular headers but make a good connection and connect & disconnect easily.  I'd like to publicly thank Wayne (doctorwayne) for his tips and recommendations on the latter.

This was one of those projects that you have to think through first before starting it but also be flexible/creative once you get into it.  I will definitely replicate what I did and learned on this project when I convert my Alco Models NYC B-11L 0-6-0 switcher to DCC.  However, being smaller - I'll have to modify a few things to make it work - e.g. the placement of the TCS M1P decoder.  With the 0-10-0, I could mount it on top of the motor.  With the 0-6-0, there's not enough clearance between the boiler shell and the motor so I'll have to place the decoder underneath the motor bracket.

This is the first time I've used magnet wire for lighting a headlight.  Hand-drilling the #79 holes through the brass headlamp and shell took a little time but worked out great.  (The biggest challenge was making sure the hole was centered in the headlamp.)  And, actually, I found soldering the 34 AWG magnet wire to the 0603 LED much easier than flexible wire because it remained straight and rigid.  To deinsulate the magnet wire I used a used #11 X-acto blade to gently scrap the coating off then tinned it with solder.

The other thing I found is that I used much more resistance to tone down the 0603 LEDs than a 3mm - e.g. 10KΩ vs 1KΩ.  I really like the dimmer appearance of the LEDs with the larger value resistors and probably could have gone up 20KΩ or more.  I wonder if the smaller size 0603 LEDs trick the eye into thinking that there is a lot of light coming from that tiny source so it needs to be reduced to look correct?  But - even with 3mm LEDs, I'm thinking seriously of adding larger value resistors because they are just way too bright normally when used for headlights.

I'll try to post some photos in the next day or two, as well as comment on a few of the challanges I encountered along the way.

Tom