Salvaged power and LEDs

[scotttmason]

Using computers daily and watching old technology gather dust in piles, it would seem that the power sources from old computers or components would be great for model use being filtered and stable. Any thoughts on this?

Also have found a lot of LEDs in old hardware (although less bright than currently available white LEDs) that would be great in structure lighting. Also am seeing new product with LED arrays as an alternate to bulbs - and reasonably priced - for flashlights, etc. To use singular LEDs or arrays from a flashlight (rated at 4.5v), is the only concern to match the voltage and polarity? Do dropping resisters need to be used for each LED or singularly if wired in a series?

Thanks,

Scott

[scotttmason]

Using computers daily and watching old technology gather dust in piles, it would seem that the power sources from old computers or components would be great for model use being filtered and stable. Any thoughts on this?

Also have found a lot of LEDs in old hardware (although less bright than currently available white LEDs) that would be great in structure lighting. Also am seeing new product with LED arrays as an alternate to bulbs - and reasonably priced - for flashlights, etc. To use singular LEDs or arrays from a flashlight (rated at 4.5v), is the only concern to match the voltage and polarity? Do dropping resisters need to be used for each LED or singularly if wired in a series?

Thanks,

Scott

[Anonymous]

That would work. Computer power supplies usually have 200 to 400 watts at 12 volts. The newer ones have varied voltage including 3v, 5v and others. This is something that I too have been thinking of using old power supplies for. At one point I had about 7 of them set aside. Although now I don't know if I still have them. Good luck with it!

PS: The only problem with using old computer power supplies is that some of them require the computer's motherboard to be plugged in, otherwise they will not turn on. I am not sure if this can be jumpered either... so just keep it in mind.

[Anonymous]

That would work. Computer power supplies usually have 200 to 400 watts at 12 volts. The newer ones have varied voltage including 3v, 5v and others. This is something that I too have been thinking of using old power supplies for. At one point I had about 7 of them set aside. Although now I don't know if I still have them. Good luck with it!

PS: The only problem with using old computer power supplies is that some of them require the computer's motherboard to be plugged in, otherwise they will not turn on. I am not sure if this can be jumpered either... so just keep it in mind.

[Anonymous]

BEWARE! The high wattage translates into high current which can melt wires and burn your railroad (and your house!) to the ground. Model railroad power packs have overload shutdown at relatively low amperage to prevent this. Computer power supplies may supply far higher amperage than model railroad wiring can take. In the event of a short on the layout, this current could be disasterous. Be sure to put a low amperage fuse or PTC device in series with each following linear or pulse regulator, and rate the fuse or PTC to the thinnest wire gauge you have used in that block. Also helps if the regulators have built-in shutdown for overload protection.

[Anonymous]

BEWARE! The high wattage translates into high current which can melt wires and burn your railroad (and your house!) to the ground. Model railroad power packs have overload shutdown at relatively low amperage to prevent this. Computer power supplies may supply far higher amperage than model railroad wiring can take. In the event of a short on the layout, this current could be disasterous. Be sure to put a low amperage fuse or PTC device in series with each following linear or pulse regulator, and rate the fuse or PTC to the thinnest wire gauge you have used in that block. Also helps if the regulators have built-in shutdown for overload protection.

[Anonymous]

I am a computer tech and tried this. Some of the problems have been addressed already. You need to us an AT style as an ATX style needs the mainboard to power up, not really, but it's too hard to get them to work without one. You will also need a constant load such as an 1157 lightbulb attached as most will not start and will shut down without a load. They will indeed melt wires, some put out 50 amps at 5 volts! Fuses cost too much in the long run. Try building a load limiter circuit, or a low tech way is to use an automotive headlight in series to limit the load in overload conditions. Another problem is they only output 12 volts. That really isn't enough to run locomotives at speed. It also won't run switch machine coils reliably. The cooling fan in them make noise, that bugged me after a while. They are good for powering lots of lights using a central power station. I found a better source of power were all the old wallpacks for old printers, modems, and speakers. They are low amp, quiet, cheap, and come in all voltages in DC and AC. They are what i use. As to didoe lighting, green, red, and yellow don't make good structure lights. First they are focused and not diffused. Second, other than a redlight district and bug bulbs where would they look right? Small ones make good signals, but for structure lights? Better source of cheap lights are white Xmas lights. After Xmas I bought 100 white lights for a $1 They ususally run on 2.2 volts each so put them in series to equal the voltage you use. They even come with sockets. I always run them a little low on voltage, 1 to 2 volts. They last forever that way. The lower the volts the dimmer and yellower they get. At about 1 volt they look like kerosine lamps. At 2 volts they look like regular lights. I use them in all my structures now. Lastly, if using wall pack, don't overload them. It's easy to do with lights and the packs will burnout and be trash. Another good thing about wall packs is it's easier to troubleshoot a small area when it goes dead than the whole layout.

[Anonymous]

I am a computer tech and tried this. Some of the problems have been addressed already. You need to us an AT style as an ATX style needs the mainboard to power up, not really, but it's too hard to get them to work without one. You will also need a constant load such as an 1157 lightbulb attached as most will not start and will shut down without a load. They will indeed melt wires, some put out 50 amps at 5 volts! Fuses cost too much in the long run. Try building a load limiter circuit, or a low tech way is to use an automotive headlight in series to limit the load in overload conditions. Another problem is they only output 12 volts. That really isn't enough to run locomotives at speed. It also won't run switch machine coils reliably. The cooling fan in them make noise, that bugged me after a while. They are good for powering lots of lights using a central power station. I found a better source of power were all the old wallpacks for old printers, modems, and speakers. They are low amp, quiet, cheap, and come in all voltages in DC and AC. They are what i use. As to didoe lighting, green, red, and yellow don't make good structure lights. First they are focused and not diffused. Second, other than a redlight district and bug bulbs where would they look right? Small ones make good signals, but for structure lights? Better source of cheap lights are white Xmas lights. After Xmas I bought 100 white lights for a $1 They ususally run on 2.2 volts each so put them in series to equal the voltage you use. They even come with sockets. I always run them a little low on voltage, 1 to 2 volts. They last forever that way. The lower the volts the dimmer and yellower they get. At about 1 volt they look like kerosine lamps. At 2 volts they look like regular lights. I use them in all my structures now. Lastly, if using wall pack, don't overload them. It's easy to do with lights and the packs will burnout and be trash. Another good thing about wall packs is it's easier to troubleshoot a small area when it goes dead than the whole layout.

[scotttmason]

Appreciate the feedback. Since I was mainly looking at structure lighting, the wall pack / Xmas lights looks very appealing and cost effective. Put several on a switchable power strip and cover all my needs. Will go commercial power for the train operation, when I get that far, as freetime for me starts around 10:00 at night. Focusing right now on kits and provisions for lighting.

Thanks

[scotttmason]

Appreciate the feedback. Since I was mainly looking at structure lighting, the wall pack / Xmas lights looks very appealing and cost effective. Put several on a switchable power strip and cover all my needs. Will go commercial power for the train operation, when I get that far, as freetime for me starts around 10:00 at night. Focusing right now on kits and provisions for lighting.

Thanks

[Anonymous]

Here's another trick, drill a small hole in the wall of a structure. Put a square of Al foil inside around the hole to keep plastic from glowing, and put pointed end of Xmas tree into the hole. CA it. Now you have interior lighting and a bare porch bulb on the outside. Make a shade from foil or whatever if naked bulbs need covered.

[Anonymous]

Here's another trick, drill a small hole in the wall of a structure. Put a square of Al foil inside around the hole to keep plastic from glowing, and put pointed end of Xmas tree into the hole. CA it. Now you have interior lighting and a bare porch bulb on the outside. Make a shade from foil or whatever if naked bulbs need covered.

[scotttmason]

Good tip flee307; have a similar technique...
Glue foil to back surface of wall, drill hole through, cut clear sprue and file to fit hole leaving .5" protruding inside structure, file and taper this part of sprue, shape other end that is exposed to exterior to look like "globe" of security lamp, etc. Then mount lamp onto flat side of sprue inside building and let the light get transmitted through to outside.

[scotttmason]

Good tip flee307; have a similar technique...
Glue foil to back surface of wall, drill hole through, cut clear sprue and file to fit hole leaving .5" protruding inside structure, file and taper this part of sprue, shape other end that is exposed to exterior to look like "globe" of security lamp, etc. Then mount lamp onto flat side of sprue inside building and let the light get transmitted through to outside.

[emdgp92]

I too use scrap computer equipment instead of buying parts from Radio Shack. There are all sorts of screws, bolts, and other parts that can be reused.

However, I don't screw around with old power supplies. I yank what I need (capacitors, resistors, LEDs, etc.) and throw the rest away. BTW, those large metal heatsinks work well for temporarily holding things together until the glue dries!

[emdgp92]

I too use scrap computer equipment instead of buying parts from Radio Shack. There are all sorts of screws, bolts, and other parts that can be reused.

However, I don't screw around with old power supplies. I yank what I need (capacitors, resistors, LEDs, etc.) and throw the rest away. BTW, those large metal heatsinks work well for temporarily holding things together until the glue dries!