Home-made paint mixer

[Hot Lead]

Just thought I'd post a home-made paint mixer I fabbed up. I did a commission recently that required a lot of shades of paint. Even though RMS paints are easy to shake, some of mine are getting long in the tooth (thickening) and shaking them was becoming tiresome...

 

I was going to buy some kind of scientific lab shaker on ebay, but even the used, crappy ones were going for $40 and might come with an unexpected gift of anthrax or something... And I had a deadline to meet so shipping wasn't an option.

 

So I made my own paint shaker out of parts I had lying around. I did some surfing and found other painters' ideas I combined into a working unit.

 

I've made one before, but it was a cheesy thing with a weighted CD-ROM motor attached to a film canister, suspended by an o-ring. I wanted something more effective, easier to use, and able to hold multiple paints at once.

 

I ran across someone who attached a motor to a plastic tray and hung it from rubber bands. It worked nice, but clattered the heck out of the paints in the tray. However, it gave me an idea - I figured the scientific shakers had some kind of rubber isolator to keep the shaker from transferring vibrations to the table. So here's what I came up with:

 

 

All told this cost me $0, since I had all the parts on hand. But, it should cost under $20 to make depending on what parts you can scrounge or buy.

 

WARNING - I provide this article as an example for entertainment purposes only, and take NO responsibility for anyone attempting to build a similar device. DO NOT attempt to do this unless you have a basic knowledge of mechanics or electronics. NO ONE under the age of 18 should attempt to build this.

 

Parts list:

• 12v computer fan (80mm or larger and at least 200mA for max. vibration)
  
• plug-in 12v DC transformer - should match the mA rating of the fan. (I used a 14v @ 100mA, though, which worked fine - higher voltages can lessen motor life though...)
  
• protective screen or mesh for fan (don't use the chrome ones with big openings- you'll see why in the description)
  
• plastic tray ($1 for 2 @ drugstore)
  
• rubber non-slip shelf liner
  
• rubber weather-stripping insulation
  
• assorted screws
  
• 4 hollow rubber feet - sourced from a DVD player, but can be found in electronic supply houses
  
• wire crimp connectors
  
• wire cutting/crimping tool
  
• on-off switch (optional) - I didn't have one handy, so I just plug it in
  
• lead foil or similar flat weight
  
• super glue or E6000
  
• double-sided tape
  
• rubber cement
  

 

As you can see the tray was just screwed to the top part of the fan's screen with some small electronics screws.

 

 

I drilled pilot holes with my pin-vise and screwed it down. I stuck the non-slip sheeting on the tray with double-sided tape. The weather-stripping foam is self-adhesive - I used enough thickness to be able to hold a bottle firmly on its side. This guarantees maximum shaking of the paint:

 

 

I then prepped the fan by gluing pieces of lead foil on one blade with super glue. (The white residue is from zip-kicker.) Flat, thin pieces of lead worked best. I could shape them to the fan blade profile before gluing. I tried a flattened fishing weight first and it flew off as soon as I fired up the fan (you DID read my warning right?!?) Tiny sticker of Iron Man can be added to fan blade later if desired.

 

 

A few pieces were enough to off-balance the fan so it shook when it turned - like a cell phone vibrator, but much stronger. (I used maybe a 1/4 oz worth of lead.)

 

Next I screwed down the fan to the tray and attached the bottom screen. The screen is crucial so if lead does fly off the fan blade later it won't shoot across the room... However – the weighted side of the fan blade is pointing at the bottom of the tray, so chances are it won’t fly anywhere dangerous but into the bottom. You can add metal mesh if you feel totally paranoid but after several weeks of using this gizmo I've had no mishaps.

 

 

I glued the rubber feet to the bottom screen with rubber cement. You can see here the hollow rubber will isolate the mixer from the surface it's on.

 

 

 

Finally I cut the leads from the fan and crimped them onto the transformer's wires. (The blue wire shown in the fan close up wasn't "live" - I assume it's for speed control or something I didn't need, so I snipped it off.)

 

Caveats – I don’t know how long the fan will last, since it wasn’t designed to spin unbalanced and push air against a solid plastic surface. Eventually the bearing will go, but it’s easy enough to get a new fan. The transformer doesn’t get hot after 5 minutes’ straight shaking so I assume I’ll never have to replace that…

 

So how's it work? It doesn't vibrate my workbench - all the shaking goes into the paints. The tray slides over maybe a 1/2 inch when it first spins up, but then settles into a groove and won't move again. See the video for a sound level - it's much quieter than a computer fan when it's at max cooling. Quiet enough to be of no disturbance at night (my studio is next to my daughter's bedroom.)

 

 

Here are some examples of paints I shook. The Vallejo red hasn’t been used for 5 years (I’m not lying! - ever since I switched to RMS paints.) 2 minutes shaking and it pours almost like new! The RMS paints were thinned perfectly in 1 minute or less, though some bottles thicken up with time (even a mixer won't fix that!) so a little distilled water may help with older bottles.

 

As you see, the tray can hold up to 6 paints side by side, but I wouldn't add more than that or the rubber feet might compress too much from the weight.

 

And it does a decent job of rolling dice too - though probably not fast enough for most gamers...

 

 

Not bad for 30 minutes' work! ;)

[psyberwolfe1]

Nice! I love projects like this.

[ulrikk]

Nice work. Have you tried using it to strip paint? Maybe if you put a jar of water + solvent + minis over the gizmo, the vibrations might just be strong enough to loosen the paint. Like an improvised ultrasonic cleaner. I really doubt that it would work, but if it did it would be a boon to geekdom. :)

[Hot Lead]

Nice work. Have you tried using it to strip paint? Maybe if you put a jar of water + solvent + minis over the gizmo, the vibrations might just be strong enough to loosen the paint. Like an improvised ultrasonic cleaner. I really doubt that it would work, but if it did it would be a boon to geekdom. :)

 

Hmmm, haven't tried that but that it would work. Honestly I have an ultrasonic cleaner I've tried for stripping paint like this. However, I haven't really seen any big difference in stripping when I used it. The stripper I use seems to make the biggest difference of all.

 

I did try to use the ultrasonic cleaner to mix paints when I first got it, but it was too much of a pain to put the bottles in something waterproof, fill with liquid, drain, etc. It's also why I decided to make something that works "dry".