Chris,
34AWG is 0.0063" OD so a #80 (or 0.0135" OD) would be more than adequate for your drilled hole. And I would recommend hand-drilling it with a pin vise (vs dremel) and choking up on the drill bit to minimize flexing, which can lead to breakage. If the drill bit is new then it shouldn't take too long for the bit to cut through the front of the boiler - even hand-drilling. Just take your time and apply moderate pressure; letting the bit cut the metal.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
That looks great, thank you.
What size drill bit for the 34AWG magnet wire would be right?Thanks again, great results.
If you are going to go the SMD route I would recommend no larger than 0603 "warm" or "golden" whites LEDs and use 34AWG magnet wire to minimize the hole into the boiler. For adhering the SMD LED inside the headlamp, I would recommend Testors Clear Parts Cement & Window Maker. It holds well and dries clear and can be removed, if needed.
I used the above for wiring front & rear headlamps on some brass locomotive installations and was very happy with the result. And, because the LEDs are so small, I ended up using MUCH higher resistor values - i.e. 10K vs 1K. I think it makes the headlamp appearance and output much more prototypical looking:
Here's what the 34AWG magnet wire looks like installed. Its small gauge helps make it less conspicuous:
Any thoughts on how to add a working headlight to an old Mantua 0-6-0 like this one? My thoughts would be to put a surface mounted LED in the light receptacle in front. Drill a hole behind it through the boiler to run wires back to the motor or a decoder.
Are there any light bulbs that would reasonably fit into the front headlight "dish"?Thanks for any ideas.
https://photos.app.goo.gl/ryqFEVSvobsvE7rK8