Tired of looking at your speedometer to know how fast you're going? make a wind-speed-meter calibrated to your car's speedo.

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
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.
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.
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.
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.
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).
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
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...
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.

About This Instructable




Bio: Will Bosworth, developing projects for HowToons @ SquidLabs.
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