The mini painters drying/curing chamber

   So, I made a thing. It’s a thing almost nobody needs. The thing is, when you need this thing, you need it like nothing else ever. (Everyone needs a Thneed…)

   Yes, I present the miniature painters drying/curing chamber. In a nutshell, this is just a very low power heater and two computer fans in a box. The low power heater is just there to provide a LITTLE warmth, but not necessarily heat. The fans are the key part, since acrylics dry more with air movement than heat. (It’s an evaporative process…)

   The one I built is proof of concept, and it works. It is neither pretty, nor does it use the best materials. I am certain there are far better choices for materials out there, feel free to experiment and tell me all about it. I would love to do a version 2!

   This is not a step by step tutorial, but rather a series of ideas stitched together with pictures. You’ll get the idea as we progress.

What you need

• A box to be the chamber. I used a “Really Useful Box” in the 9.1 liter size. I chose it because it had nice straight sides to mount the fans on and it also fit the size of the heater nicely. $12.00
  
• A power transformer of 12VDC or less. You can find these labelled as ‘chargers’ all over the place. You probably have some in a drawer somewhere that you can’t recall what they charge. The output has to be less than 12v DC but more than 5v DC. The fans normally look for 12 VDC but will also work on 5 VDC at a much slower speed. I found one that was 8.7VDC. You will cut the end off, so make sure you don’t need it for anything else.
  
  
  
• 2 Computer fans – I used 80mm fans I got from Best Buy for $6.99 each. You don’t want super-fast rotational LED lit OMG fans. Just cheap 12v computer fans. (More on why later)
  
• A reptile heating pad. They sell these at pet stores, they must be avoided at all costs!!!! The pet store markup is on average 300%. I found the same reptile heating pad on amazon (7w) for $9.99 while at the pet store is $39.99. I went with 7W because it is low heat and won’t burn the plastic box, while still providing some ambient warmth in the box. Remember, we want warm, not hot.
  
• A rack of some kind to set minis on. I used granny grating from a Hobby Lobby, you might find a nice metal rack or make something of your own… Be free, choose wisely! (Granny grating is the latch hook rug stuff you can find at craft stores in the yarn sections. It’s just plastic sheet with lots of square holes in it. Makes great basing and terrain material too. It’s about $2 for more than you’ll ever use ;)
  
  
  

You will need some tools as well.

• A soldering iron to connect the wires on the fans and maybe the heating pad as well (if it has a regulator switch). If you are not handy with a soldering iron, you can use wire nuts from the hardware store and splice connectors from the same store.
• A Dremel tool to drill the holes in the box. You could also use just a regular drill and bits, but the Dremel makes it faster.
• A multi-meter. You need this to check the polarity of the wiring of everything. You can get them super cheap at Dollar stores, Wal-Mart etc. You do not need a Fluke $300 job, just one that shows volts DC.
• A wild sense of abandon and experimentation…

A note on safety

 

YOU WILL BE WORKING WITH ELECTRICAL WIRES. NEVER SOLDER OR WORK ON ANY PART OF THIS WITH ANY THING PLUGGED IN TO A LIVE OUTLET. YOU COULD DIE!!!!!!!

Yeah, I know, safety warnings are lame, but seriously, make sure this stuff is unplugged before you do anything. Don’t be a Darwin award winner.

Assembly steps. Kinda…

   First up, measure and drill the holes for the fans on the opposite sides of the box. I drilled the first hole, started the screw to hold it in place then drilled the rest. One the holes are drilled, you’ll need to remove the plastic on the box for the fan to blow through. I found the easy way was to mark the opening for the fan, then drill a bunch of holes in the plastic, then used a hobby keyhole saw to “connect the dots”. I mounted my fans inside the box, just to make it easier to store and not worry about knocking the fans about. You do lose a little room, but it’s not a big deal.

 

   I also mounted one fan near the bottom of the box and one closer to the top. I ‘think’ it gives a little better airflow, but who knows. As you mount the fans, take a note of the direction of the airflow. Each fan will have an arrow on its case that shows which way the air flows through it. You’ll need to mount one fan to ‘pull air in’ and the other fan to blow the air out. This will make sure that all the air that goes through the box will flow across the minis in the box. 

   Next, you’ll need to install the heater. Mine has a big power regulator/switch about halfway up the cord. There was no way I wanted to drill that big a hole in the box, so I marked my cord and cut it. If you’re not seriously confident of your electrical skillz, just drill/cut a hole big enough for the cable then use duct tape to close it up. If you are confident in splicing/soldering the cables, just separate the 2 cords of the cable, mark it with tape in two places and cut away. The splice them together after you run it through the hole in the box. MAKE SURE IT IS NOT PLUGGED IN!!!!!

   Just place the heating pad on the bottom and either tape or hot glue it down.  Simple as that.  Run the cord out and you're almost home.

   Now, to wire the fans. This is fun. The fans will have a red wire, a black wire and a blue wire (normally). Red is positive, black is negative and the blue wire is not needed here. (It reports the fan’s RPM to the computer in case you’re wondering.) We want to but the wires off as close to the computer connecter as you can. Then cut the blue wire off and throw it away or save it for other projects. Also cut off the power transformer near the tip.

   This is where you need the multi-meter and SAFETY! Strip off some wire from each side of the transformer cable. Make sure the exposed wires stay separate (Tape them to your work surface so that they do not touch.) Plug the transformer in and use the probes to find the positive wire. (The red probe will be on the positive wire when the meter indicates positive voltage. If the meter shows a minus sign, switch the two probes until you see positive voltage (no minus sign)). Mark the positive side with tape and UNPLUG THE TRANSFORMER.

  Now, either solder the newly found positive wire to the two red wires or use the wire nuts to connect them. Do the same for the black fan wires and the negative wire from the transformer. Now is test number one. Plug the transformer in and make sure the fans spin, and that that flow the air correctly (one in, one out of the box).

   To make the shelf, I just cut out some Granny grating to fit the box, leaving a space for the fans. Then I hot glued that to five, one inch long dowels and set it in the box.

  Voila! You have a mini curing, drying box.

How to use it

   The nice part about having the dual plugs, one for fans and one for heat is simple. If you just want to dry wash or a layer of paint, put the mini in, put on the lid, plug the fans in and let the air current do the work. If you need to do a more serious cure, say green stuff, texture paints or some other thick stuff, you can add the heater to the outlet.

   The heater at such low wattage is not going to warm up all that much. Remember, it’s designed to not hurt a small lizard, so it’s just going to warm the air a tiny bit.

   But Bill, can’t you do the same thing with a blow dryer? Why yes, Jimmy, you can. But while you’re sitting there holding the blow dryer on your model(s), you’re not painting other models, or building, or taking the wife to lunch. It just saves time…

   Is it perfect, naaah. It is cool though! I love it for getting washes dried in half the time as usual, and for setting texture paints on bases in short order.

  Let me know what you think. (I already know I’m crazy, no need for that…)