This is the best auto mister I have seen yet, that doesn’t cost 100+ dollars.
The parts can all be purchased at Home Depot, or a similar store. The most expensive component will run you from 29 dollars up, depending on what you choose. The only tools you need are a nut driver or screw driver for the hose clamps, and a knife or scissors to cut the tubing.

Materials:
A pump type garden sprayer. Mine was 19.99 for a 2 gallon at Home Depot.

An auto sprinkler valve. These are for the sprinkler systems that pop up out of the ground, and cost about 10 dollars, also from Home Depot.

A sprinkler timer. Cheapest I found was 29 dollars, and while you could rig something else up, I think this is the best way to go.

Plastic tubing. Cheaper than hose, use the size that your valve requires.

Hose clamps, and finally an adapter to connect the tubing to the spray nozzle.

I used the spray nozzle from the sprayer itself. Get a sprayer that has the wand attachment, this bottle has a nipple on the bottle itself, which is where you will attach the hose. If you want a fine mist, you can buy nozzles from Big Apple Herp and adapt them to your equipment, I just used one of the spray nozzles that came with the bottle.

To put it all together, cut a short section of tubing ( 10 feet of clear ¾” tubing for 3$) to run from the tank to the valve. Next, connect the rest of the tubing to the outlet side of the valve, and then cut to the length you need if necessary. This is the end that goes to the cage. The adapter I used fit the ID ( inside diameter) of the hose, and the threads on the opposite end fit into the spray nozzle. This adapter also bends 90 degrees, which means the hose runs flat along the top of the cage, connects to the adapter which then turns right, and connects to the nozzle which points straight down. I cut a small hole in the top screen, used some hose washers( those rubber things that come with spray nozzles for garden hoses, also available at HD) one on either side of the screen to spread out the stress of the connection. I then wrapped the threads with Teflon tape ( the white tape that seals threads for plumbing and air line use, HD, .99$ a roll) poke it through the screen, and threaded the nozzle onto it.

NOTE- Whenever connecting the tubing to anything, regardless of how tight it is, put a hose clamp on it, the pressure will eventually cause the tubing to come off, and unless you want the whole spray bottle ( 2 gallons in my case) to empty onto the floor, clamp it.

The next step is to fire up the brains of the operation. The original plans called for a low voltage transformer, which I had handy from some garden lights that weren’t being used. There was a problem though, all the garden light transformers step house power down to 12 volts, and the valves at Home Depot all need 24 volts to open. I spent an hour in the electrical aisle looking at various regular transformers, only to give up wiring an elaborate device that may eventually catch fire, and bought the sprinkler timer. It was a good decision, and here is why. The timer I bought is digital, with a battery backup so I won’t loose ANY settings during a power outage. ( If you loose power, the valve closes automatically, it needs current to stay open). I can connect up to and individually control 8 valves ( which means 8 cages, even if they have different needs). I can set the timer to open any or all valves for as little as 1 minute, or as long 23 hours and 59 minutes. The last one, I can close the spray nozzle so it just drips a little, and set the timer to open the valve at 8 AM, and close it at 8 PM, no water dripping all night while Bert is asleep, and I don’t ever forget, nor do I have to fiddle around with the stupid plastic valves that take a rocket scientist to get adjusted just right. Set and forget. I can have valve one( cage one) open at 10AM and close at 1002AM, the next cage opens at 1003 and closes at 1005, and so on for 8 different cages. There are 3 programs on the timer. On my setup, program A opens valve one at 10AM for 2 minutes, and program B opens valve one at 4PM for 2 minutes. For the winter I am going to get another 10$ valve, and set the nozzle to drip, have program C open the valve at 8Am and close it at 8PM, the same time the lights are on, and close program B all together. This way, Bert has 2 hours to warm up in the morning, then the cage gets sprayed ( it is like a gentle rain) for 2 minutes, plus a drip all day for drinking, and no spray in the afternoon, since the room gets chilly at night. It is worth noting that all 3 programs will open any and all valves that you choose whenever you want. They will only open the valves you set it to, for as long as you set it to, and when you set it to. It is entirely up to you how you want it set, and any and all arrangements you can think of are possible.

One thing you might want to consider, is purchasing a spray tank with a Pressure Relief Valve on it. This allows you to release the pressure in the tank, so that you can unscrew the top to refill it without tearing the gasket. Mine does not have this, I am using the bleed screw on the valve itself for this, but am planning to drill a hole in the top of the tank and install a petcock( like on the bottom of you radiator to drain coolant in a car) for this purpose.

With one valve opening for 2 minutes twice a day ( 4 minutes total) I use 2 gallons of water every 7 to 8 days, and have to pump the tank to increase pressure every 4 or 5 days.

The most expensive component is the timer, which you only need one for every 8 valves. If you use a T adapter in place of the elbow that I used on my cage, you can put as many nozzles as you need to cover a very large cage, all on one valve, so each valve can work a different cage, or do different things on the same cage ( the spray AND drip on one cage would be 2 valves). Valves cost 10 bucks a piece, and you can probably get the garden sprayer cheaper than I did, especially if you wait for an end of season sale.

The cheapest system I have seen online or at shows is a around 125$, and they only do a maximum of 3 cages, to do 8 you need 3 systems. With this, you need 1 30$ timer for 8 cages, if you don’t want to spend 10$ a cage, then you run T’s to do 2 or 3 cages on one valve. I would spend the money for a valve on every cage. You do NOT need a separate tank for each valve, manifolds to connect the tank to all 8 valves are cheap, but you would need to refill the tank more often. You can have any or all the valves opening up to 3 times a day for as little as one minute each, up to 23 hours and 59 minutes each, all at once or one at a time( which would save the pressure in the tank). If you lose power, it closes all the open valves( no over spraying in a cage) and will automatically pick up again when power is restored. ( Not the program itself, but will do whatever it is supposed to do at the time power is restored, and continue from there. After all, you don’t want the power to come on at 3AM and have your cages sprayed down, unless you programmed it that way).

It’s a great system, cheaper than anything else out there for 1 cage, MUCH cheaper for multiple cages and cages with different needs than everything else in your collection. I should have figured this out on my own, but I didn’t. I would be remiss not to give credit to the person who did this before me, even though I modified it a bit. The link to the original web site ( AFAIK this was the guy who designed it) is http://www.trix.com/binx/mister/

He also has his setup to operate off some kind of Home Manager program on his computer. If you want to go that route ( I have no idea why, the timer is more versatile, but if you are a geek it may appeal to you) he shows the program language on how to do that.

The only thing I had a gripe about was the instructions on how to wire and program the timer were in Spanish and French, no English. I was able to download the English manual directly from Toro, but was miffed at the hassle. ( I live in the US after all).

If the idea of assembling this system gives you the willies, keep in mind that all the systems that you can buy from herp stores or shows require the same amount of assembly, the only advantage is that it all comes in one box, but you pay for that convenience.