Instructables
Tired of looking at your speedometer to know how fast you're going? make a wind-speed-meter calibrated to your car's speedo.
 
Remove these adsRemove these ads by Signing Up

Step 1: Parts Layout

The dimensions of the wood used in this project are scale-able. I eyeballed based on availiable wood lying around.

- 1/2" X 12" X 12" plywood

- ~ 2' 1/2" X 1" plywood

- some nails & a hammer

- string & a pen

- drill & bits, jigsaw

Step 3: Attach handle

Attach the handle with a few nails. Make the handle comfortable for you. Ours is at a 45deg angle to the perpendiculars because that seemed like the most comfortable for holding out a window.

It may be easier to attach the handle with woodscrews instead of nails, but nails keeps things simple.

After attaching the handle, you've made plenty of other functional things including: a serving platter, a handy-sheild, a portable shade device.

Step 4: Attach wind-meter

Pull out the nail used to draw an arc in the wood plate.

Drill a hole just wider than the nails you are using into an end of the rod.

Nail (through the rod) into the hole used to draw an arc. If the hole sued to draw the arc is busted,try to nail fairly close to it. The head of the nail should be almost flush with the rod but the rd should still rotate freely about the axis. Try not to use a nail that goes through both pieces of wood.
jkoyne2 years ago
For the aerodynamics, what about making the gauge small enough to place on the radio antenna? possibly out of plastic? Of course, now everyone else on the highway can see your speed also.
static7 years ago
Stuffed in the closet a have giveaway from a bank or supply store a "weather Station". Along with the rain gauge it has a similar wind speed indicator that swivels to act as a weather gauge as well. The boy scout weather badge hand book used to detail how to construct this as well.
bhunter7367 years ago
I like the simplicity of it. Very useful for checking wind speed. If the wind is blowing over 30MPH I'll be indoors or hiding anyway. This could be great on top of my wind turbine for rough wind speed calculations. After all, most of the year the wind here is between 10 and 20MPH.
tomtom8 years ago
I think you need to have it held further from the car as the wind spped close to the car will be greater because of the displacement by the cars bodywork as it travels through the air. I think you would need to rig up somethin to hold it away from the car.
radiorental8 years ago
Isnt this a bit of a logarithmic scale meter, the faster you go the finer the increase? So as your hurtling down the speedway you really have to concentrate between break neck and broken neck speeds???
You're right about the smaller increments. But as for the day-to-day use of it there's not too much of a need for a wind meter that accurately measures 80mph. Also, how accurate is the wind speed right outside the window of a moving car? It's going to be thrown off by the aerodynamics.
it would be helpful to know whether or not you reach 88 mph. ....(you know, for time travel)
I can think of a few uses for 80mph.... One of them is about to slam into Florida (right where my sister goes to school -- but at least she is not there this week).
mikesty8 years ago
If you're going slow, I don't think it'd move that much?
You would be suprised, even with the nail in tight at the top, it will still read very low speeds. Like radiorental said, the faster you go, the finer the increase, so when you are going slow, the read-outs are a lot more drastic.
well, the really cool application here is as both a wind vane and wind meter. I can see this being useful as part of a wind generator turbine
howtern (author)  mikesty8 years ago
Well...in the photo, you can see that the unit is crooked with respect to the ground and/or direction of travel. But after two mock-ups and a few calibrations of both, the jump from 0 to 10 mph is i-think-we-did-something-wrong-large, until you see it happen ovedr and over and then do some thinking. don't forget that cosine term...
ElectricJ8 years ago
I don't know if this is something I would want to attach to my car, but it looks like it might be useful for homebuilt type things that don't have a speedometer. Good idea.