PortaCooler mobile evaporative shop cooler project

This is a project to build a new version of a mobile evaporative cooler that I designed and built 20 + years ago. That unit utilized an Arvin stainless 3 pad cooler. For this project, we will be using one of the new window type evaporative coolers that is made out of Fibre Reinforced Plastic or FRP and uses a Master Cool type fabricated pad.

First we need to make a dolly type base with 360 degree swiveling casters that will support 750 lbs. This is figuring the weight of the finished cooler at 600 lbs loaded and a design margin of 150 lbs. A trip to Harbor Freight took care of the casters, got these nifty double wheel full swivel casters (220 lb rating) for something like 5 bucks ea!

Now we build a frame to support the cooler and install unit.  Barrel is a poly drum that I picked up for 25 bucks or so. Used to hold some type of soap or food grade liquid. It was clean and no residue. Came with metal drum head clamp.

Added a diagonal brace to the cooler bracket and touched up a couple things and we are ready for a test run. For the time being we will be using black plastic supply tubing with a hose end fitting for water feed. Eventually i will install a float mechanism into the drum with a hose end fitting so I can just hook up the hose, fill the cooler automatically and then disconnect and roll it to where the cooling is needed. Also I will be looking for a submersible pump to install in the drum to feed the cooler pad. Since the water reservoir is below the water level of the drum when it is full I am going to have to ponder how I am going to rig a pump to keep the water recirculating properly. I may even play around with a siphon feed from the drum to the coolers float valve, I could probably use the pumps bleed orifice to prime the siphon. Like I said, need to ponder this some more. Meanwhile it works great and the plastic tubing is functional, cheap and doesn’t really limit the mobility that bad.

I  may play around with extending the duct and a couple other tricks I learned from the first one but for now, it works just fine. Will have to spray the frame either International Red or Kubota Orange ASAP. Gotta keep up appearances dont ya know!

Lo Buck Anemometer – CD Rom Drive Dissection

Hi All,

I recently got re-interested in building a quality low cost cup type anemometer (last one I built was like 35 years ago in grade school science class) which would be handy for wind generator siting evaluation.  I will warn you upfront, you can buy a really nice unit off E-bay complete with data logger and direction for around 100 bucks plus shipping but wheres the fun in that? My thought is to recycle old technology and build something nice and usable for less than 10 bucks, a little effort and expand ones mind at the same time.

These days “If you give a kid a fish he will look at you and go huh? What the hell am I supposed to do with this? But if you teach him to fish and how to prepare his catch he will have McFish for life”.

Tools needed: Small phillips screwdriver and small flat blade to pry with.Tip: Harbor Freight. IIRC this set cost me around 10 bucks and has given good service.

Next find a suitable obsolete disc drive; heres the one I used:

OMG, not the "Void the Warrantee" warning!!

Taking out the 4 case screws and the faceplate and we are here:

BTW, in case you have always wondered what that little hole in the face of CD drive is for, Wonder no more! You will find a paperclip perfect for getting the drive open/faceplate off:

Depressing 3 tabs on the back side and the circuit board assembly separates !! Gently ease the ribbon conductor (white one on the left) running to the motor out of its connector on the circuit board. We want to keep this intact to make connecting our data leads easier.

Here is the permanent magnet stepper motor that we are going for. Small but with very large high speed bearing for its size. Think how fast CD drives spin.

3 Screws and its out! Wow, look what I found inside, no wonder this drive didn’t work LOL!

For the younger generation that is a Kennedy Half Dollar; used for size reference. This is what REAL money used to look like. See also: Gold and silver standard, the demise of the American monetary system or how we all got screwed…

This is the tab that holds the motor casing with the magnets from popping off. If I decide I need to open the motor I can cut this rivet with a pair of dykes so as to not get metal filings in the bearing. I can use a small screw to hold the tab down afterwards.

Now I just have to come up with some type of light plastic bottle to make a shroud for the motor to protect it from the elements. I am going to hit up the pharmacist at the local CVS to see what she has for a suitable pill bottle. Will have to come up with a usable spider for the cups, thinking about checking out chopsticks and a tinkertoy spool but nothing has grabbed me yet. So far the only thing I see that will be kinda tough is finding 3 plastic Easter Eggs out of season to use for wind cups. BTW, for wind direction the simplest thing is to wet your finger….

Well gotta go fish a while, getting hungry. More later when the mood strikes. Would love ideas for a simple elegant low cost solution for a 3 spoke spider to mount the cups on. Given the size of the motor I would imagine 6-8″ diameter would be just about right, and preferably light.

Feel free to kibbitz. David Chapman.