Make/wire a cheap DC smoke unit?

You might look into the Seuthe smoke unit, they can be had pretty cheaply.  I have a bunch of them from upgrades...

The ones I have run on 6V AC or DC, and draw about 250 milliamps with a brief surge of around 400 milliamps on cold startup.

To power the Seuthe smoke unit, if you have an old ATX computer power supply you can get a pair of these and hook up lots of low voltage DC items to it and put a switch in line with each circuit you want to turn on and off.  Alternatively you can just disconnect one side to turn it on and off.

https://www.amazon.com/gp/prod...le?ie=UTF8&psc=1

John

@Mannyrock posted:

Hey Guys,

  I would like to have a very cheap DC smoke unit, to place inside of one of my little buildings.

   Correct me if I am wrong (please), but it is my understanding that Marx made cheap DC steam locomotives with smoke units in them, for the smoke stack.  I remember my cousin having one in the 1960s, and it used smoke pills.   (His little sister ate one of the smoke pills and my uncle had to take her to the emergency room!)

   Wouldn't it be possible for me to buy one of these cheap locos, open it up, pull out the smoke unit, hook it up to a small DC transformer, and get it working?

Happily, I can buy a little DC Train transformer (with forward/reverse speed controller) for only $5.00 at the thrift shop train store.   (They have several Bachman's in good shape.) They also sell old Marx locomotives for cheap as well.

Thanks for any advice, admonitions, or information.

Mannyrock

In a word, DON'T.  You don't know it's condition or suitability for your purpose.  Take Gunrunner's advice - Seuthe makes smoke units for a very wide variety of uses (including specifically for placement in structures).  Exercise CAUTION.

I just recently averted a fire from a large smoke unit that failed.  Had I not been standing over it, I would be repairing / replacing a huge structure, or part of the layout, or even the house. 

George

Another option is the inexpensive water vapor mist unit.  Just a few bucks, 5v DC, puffs out water vapor just like smoke.  Great for buildings.  Just need to keep an eye on condensation.

For buildings I think the water vapor unit is a worthwhile consideration, I was quite impressed with what I got for $5, four of them!  The only thing that didn't come with it is the actual power brick cable.  You get the wick, driver board, and the emitter and enclosure.

They certainly put out plenty of vapor for an impressive building smoke stack.  You can slow down the stream by putting tubing above it, this also allows you to put the emitter down in the building.  The wick can be cut very short, it just transfers the water up to the transducer that then emits it.

Here's a quick demo.  It also doesn't need refilling nearly as frequently as a smoke unit, with the proper sized water container, it'll run for several hours without being attended to.  If it does run dry, it doesn't do any damage to it running dry.

@gunrunnerjohn posted:

For buildings I think the water vapor unit is a worthwhile consideration, I was quite impressed with what I got for $5, four of them!  The only thing that didn't come with it is the actual power brick cable.  You get the wick, driver board, and the emitter and enclosure.

They certainly put out plenty of vapor for an impressive building smoke stack.  You can slow down the stream by putting tubing above it, this also allows you to put the emitter down in the building.  The wick can be cut very short, it just transfers the water up to the transducer that then emits it.

Here's a quick demo.  It also doesn't need refilling nearly as frequently as a smoke unit, with the proper sized water container, it'll run for several hours without being attended to.  If it does run dry, it doesn't do any damage to it running dry.

That's what I love about the forums -- the free exchange of ideas!

In several recent threads, I have waxed eloquent about the potential for using ultrasonic transducers, of the type discussed above, for simulating 'smoke' on the layout. When GRJ recommended the Suethe units for the same purpose, noting that he had a bunch left over from upgrades, I wrote him and offered to buy a few to experiment with. We struck a deal, and after breadboarding one to test, I can see that, even at full retail price (about $20 or so IIRC), the Suethe units are an elegant and reasonably priced solution to small smoke simulations. The only downside is the need to periodically recharge the smoke unit with smoke fluid

Imagine my surprise, then, to see GRJ heading the other direction, experimenting with the inexpensive transducers and reaching pretty much the same conclusion I had about their potential! FWIW, I fully agree with his hot takes on the cheap misters (though I do note that, if you run out of old surplus micro-USB cords, the local dollar/5 below-type store or "slow boat" online sources have them in stock, cheap!).

Well, I've used smoke units of all shapes and sizes, but I was intrigued with the misters when they were mentioned a few months ago.  I risked $5 at Aliexpress to buy four of them, and I can see where they'd fit the bill for buildings.  Some folks have expressed concern about the humidity and any droplets they leave.  I can see that might be a concern if you get carried away with them, but I doubt one or two will have much effect.

The plus with something like the Seuthe smoke unit is the size for a self-contained solution.  I think both deserve consideration, depending on what you're environment is.  I sometimes wonder why the Seuthe smoke unit wasn't used in smoking caboose models, they're the right size, and there's less risk of a meltdown than the kludge they put in smoking caboose models now.

John, Do you have item  details for the mister from Aliexpress I also would like to pick up a couple? Thanks

@lstoll posted:

John, Do you have item  details for the mister from Aliexpress I also would like to pick up a couple? Thanks

It's item: 3256806512738082 on Aliexpress.  I bought the ones that were separately bagged like the shot below.   Truthfully, the ad was a little confusing and I wasn't sure what was included, so the separately bagged one seemed like a good idea.  Shipping ends up being the most expensive thing, it's $3.63 for four of the 84 cent packages.

thanks john

Wow.  Great advice from everyone, and you saved me from rigging up something dangerous!  (Hitting 70 now, and I sometimes forget to turn stuff off.)

I am going to go the mister route.  I have an extremely dry basement, kept at about 55% humidity by my dehumidifier.  So, any drops of water or condensation don't last for long.

And now, my ignorant follow up question.  The misters that Gunrunner suggested are 5v DC.  Can I still use a small HO transformer, setting the dial on 5v, or will this create too many amps/joules/watts, whatever, and burn out the mister?

Also, Gunrunner, you said you bought the separately bagged item (version C).  Does this mean you had to buy 5 different items? Or, did you actually get all of these items as a bundle in a single purchase?

Thanks,

Mannyrock

@Mannyrock posted:

And now, my ignorant follow up question.  The misters that Gunrunner suggested are 5v DC.  Can I still use a small HO transformer, setting the dial on 5v, or will this create too many amps/joules/watts, whatever, and burn out the mister?

You might be able to cobble something together, but by far the easiest way to power this type of device is an old-school micro-USB cable (not the newer USB-C) which will plug into the PCB and connect to any open slot on a powered USB hub or PS.

If you're like me (a packrat!), you probably have a few such cables and/or USB wall warts salvaged from obsolete gear, and if not, the local dollar store or 5 below shop will have them cheap. And as for "burning out" the PCB, if the supply voltage is correct, it won't matter if the PS is more robust than needed.

@gunrunnerjohn posted:

It's item: 3256806512738082 on Aliexpress.  I bought the ones that were separately bagged like the shot below.   Truthfully, the ad was a little confusing and I wasn't sure what was included, so the separately bagged one seemed like a good idea.  Shipping ends up being the most expensive thing, it's $3.63 for four of the 84 cent packages.

Ordered four of these.  Totl said $7.51 charged to PayPal.  Initially said the expected delivery date as I ordered it would be Oct 7 - 16.

Got a notice that it shipped and that expected delivery date:  12/10/24  !!!

Click on the order and click "invoice" and it says the total is over $50. Fortunately PayPal has already been charged so if they try to charge any more I will refuse.

Not the first time I have experienced this with AliExpress,  Sometimes the price changes when you put it in the basket, sometimes the price changes after you order it, sometimes the item changes.

There are definitely bargains to be had with AliExpress, but the functionality of the website and order processing is really screwed up.

John

@Mannyrock posted:

Wow.  Great advice from everyone, and you saved me from rigging up something dangerous!  (Hitting 70 now, and I sometimes forget to turn stuff off.)

I am going to go the mister route.  I have an extremely dry basement, kept at about 55% humidity by my dehumidifier.  So, any drops of water or condensation don't last for long.

And now, my ignorant follow up question.  The misters that Gunrunner suggested are 5v DC.  Can I still use a small HO transformer, setting the dial on 5v, or will this create too many amps/joules/watts, whatever, and burn out the mister?

Also, Gunrunner, you said you bought the separately bagged item (version C).  Does this mean you had to buy 5 different items? Or, did you actually get all of these items as a bundle in a single purchase?

Thanks,

Mannyrock

If you look at my previous post, you'll see that I simply selected the bagged complete set and then bumped the quantity to four.  You can buy all you want at 84 cents each.

As for the power supply, Steve is on target, don't screw around with an HO transformer, it's not nearly regulated enough for the board!

If you don't want to use a simple wallwart and USB cable, use one of the AC to DC switching power modules connected to accessory AC power, set it to output 5VDC and make yourself a USB power cable.  The cables I've cut apart have red and black for the power and ground, and the other wires are for signals that will be unused in this application.  So, take a 99 cent USB-A to micro-USB cable, whack the USB-A connector off, and connect the red and black leads to that 5V switching module I mentioned.

@Craftech posted:

Ordered four of these.  Totl said $7.51 charged to PayPal.  Initially said the expected delivery date as I ordered it would be Oct 7 - 16.

Got a notice that it shipped and that expected delivery date:  12/10/24  !!!

Click on the order and click "invoice" and it says the total is over $50. Fortunately PayPal has already been charged so if they try to charge any more I will refuse.

Not the first time I have experienced this with AliExpress,  Sometimes the price changes when you put it in the basket, sometimes the price changes after you order it, sometimes the item changes.

There are definitely bargains to be had with AliExpress, but the functionality of the website and order processing is really screwed up.

John

I've never seen anything like that  with Aliexpress, and I've ordered hundreds of items over the years.  I have had issues with a few products, but I've always gotten them resolved satisfactorily except for one when I missed the cutoff date for complaining, my fault.  Modifying the total after the sale goes through seems to be a major screwup!

I just looked, and it seems fine to me, I put them in the cart, but I didn't actually order them.  They claim to have over 9,000 in stock and ETA from Oct 7 - Oct 16.

@gunrunnerjohn posted:

I've never seen anything like that  with Aliexpress, and I've ordered hundreds of items over the years.  I have had issues with a few products, but I've always gotten them resolved satisfactorily except for one when I missed the cutoff date for complaining, my fault.  Modifying the total after the sale goes through seems to be a major screwup!

I just looked, and it seems fine to me, I put them in the cart, but I didn't actually order them.  They claim to have over 9,000 in stock and ETA from Oct 7 - Oct 16.

They have taken care of the problems, but it is more work than it should be.  The order went through for the correct items this time.  I was referring to some past experiences.  The shipping date they emailed me may be also wrong and it will actually come in Oct as they stated when I ordered.  The invoice for over $50 may just be a clerical error and they won't charge me more than the $7.51

Maybe it will be like the Toyota Diagnostic Scanner I ordered which was cancelled because "none were available in the US" so I had to order it at a higher price from the factory in China which shipped it FROM THE US anyway.

Maybe it's me?

John

@Craftech posted:

Maybe it's me?

John

Maybe it's your name.  I hope it doesn't spill over to more John's, I don't those kinds of problems!

Got an update that in fact they would be delivered in December yesterday.  I go to the mailbox and there they are (October 5).  It was shipped from Perth Amboy, NY

For the money I shouldn't complain.  At least they didn't try to bill me nearly $50 extra.

The setup as described on the package shows the two halves of the plastic holder closed over the mister unit.  Since that would pinch the wires soldered to it are you filing a notch in the plastic holder to clear the wire?  It also comes with what looks like a long solid wick which I guess can be cut to length.

Thanks,

John

I got to play around with ultrasonic misters not too long ago:

https://ogrforum.com/topic/is-...-the-future-of-smoke

They are pretty neat and show some promise.

@Craftech posted:

Got an update that in fact they would be delivered in December yesterday.  I go to the mailbox and there they are (October 5).

For the money I shouldn't complain.  At least they didn't try to bill me nearly $50 extra.

The setup as described on the package shows the two halves of the plastic holder closed over the mister unit.  Since that would pinch the wires soldered to it are you filing a notch in the plastic holder to clear the wire?  It also comes with what looks like a long solid wick which I guess can be cut to length.

Thanks,

John

There should be a notch in one of the halves of the black plastic holder that the wire passes through.  The wick needs to reach into your water reservoir to wick up the water - you can cut it to length.

@Mallard4468 posted:

There should be a notch in one of the halves of the black plastic holder that the wire passes through.  The wick needs to reach into your water reservoir to wick up the water - you can cut it to length.

No notch.  I'll just cut one.

Thanks,

John

@Norm Charbonneau posted:

I got to play around with ultrasonic misters not too long ago:

https://ogrforum.com/topic/is-...-the-future-of-smoke

They are pretty neat and show some promise.

That's really helpful.

Thanks Norm.

John

@Craftech posted:

No notch.  I'll just cut one.

Thanks,

John

Nothing wrong with cutting a notch, but I have several of these units from multiple sources; they've all had a notch, although it can be hard to see.  Here's a lousy picture of what it looks like.

@Mallard4468 posted:

Nothing wrong with cutting a notch, but I have several of these units from multiple sources; they've all had a notch, although it can be hard to see.  Here's a lousy picture of what it looks like.

OK,

I didn't snap them together.  Now I see it..

Really appreciate the photo. 

John

Works great.  Kind of fun as well.

Thanks everyone for the suggestions.

John