Does anybody know a manufacturer that can make custom bulbs to order?

We need bulbs with a B22 base, a bayonet base with double contacts. We need them in 65 volt and 83 volt, where 110/120 volt will function.

These are standard for quite a few Danish diesel locomotives of 1950's vintage, which we have operating as primary power in many museums.

Ew. Good luck. I don't think you're going to find those B22D bulbs in incandescent at any voltage. Most of those manufacturers are gone or switched to LED. If just general lighting, then 110V warm white LEDs may work for 83V, not sure about 63V - if you can get them. But for headlights, nada. Here in the states, B22D bulb applications seem to be rare.

Did you mean "where 110/120 volt will NOT function."?

B22 is common throughout Commonwealth (ex British Empire) countries like Australia. We've replaced a lot of incandescents with 24V LED's in carriages. I'd give LED's a try in your 65/83V situations, they will work over a range of input voltages. Or maybe rig up a voltage down converter (inverter) circuit board.

Later: This page suggests it may be as easy as changing the dropper series capacitor to get a 240V led to work on 83V (or even leave it out altogether for 65V operation).

http://www.bigclive.com/ledlmp.htm

As much as I dislike "adapters" because they often make things less reliable these are available;

https://www.amazon.com/Simpo-Adapter-Co ... d_source=1

These should open up the number of Incandescent/LED light bulbs that might match your voltage requirements.

Someone might hardwire (solder) a modern LED bulb into this adapter and pot the junction with "5 minute epoxy" for durability.

Good luck, Kevin

I would check with this company: https://marteklighting.com/ .
They make a lot of unique voltage led replacement bulbs.

If they don't have anything, perhaps they would share the electronics they use to run their bulbs over a wide voltage range.

We have bought some 32 volt bulbs that were NOS from aviation company. I am not sure how we found them, but we bought 20. So there was overlap there.

Andy

Update - our project responsible found some new old stock from a vendor in a neighboring city, and we purchased all of it. So I guess our needs are protected for at least 10 years.