Wind vane project

[Tractor manParticipant @tractorman]

Hi all.
I am.planning a roof mounted wind vane for my house. I have seen vanes mechanically connected to the inside of the house where a compass dial indicator shows the wind direction. I’m happy with the hearing and drive but wondered if anyone had any thoughts on the business end, i.e. the arrangement of bearings and support tube to provide a strong and weather proof pivot for the arrow to mount on and allow a central shaft to run through it indoors to the proposed indicator location.
I live in a bungalow so the drive shaft will only have to descend a couple of metres. Regards

[Tractor manParticipant @tractorman]

[Jeff DaymanParticipant @jeffdayman43397]

I saw a wind direction indicator many years ago that used a bicycle hub as the support and bearing. It had the axle welded to a V shaped sheetmetal piece that fit the ridge of the house roof. The builder had rigged a magnet to the hub and had 8 reed switches arranged around it. The reed switches were wired to lamps on a compass board inside the house to indicate the wind direction. For weather proofing, the hub had a sheet of rubber draped over it pierced with a snug fit for the vane shaft, and fastened with wire around the base of the hub. Reed switches are waterproof and there are no exposed contacts. The magnet must be arranged to pass very close to the reed switches to actuate them.

I guess if you wanted a mechanical indicator the bike hub mentioned above could be mounted stationary and the upper shaft fastened to rotate with the vane, the lower shaft could be coupled to a rigid drive to inside the home, or maybe coupled to a bike speedometer cable to take it indoors to the compass indicator.

Bike hubs are cheap and available and have very low friction.

All the above just food for thought. Good luck with the project.

[clogsParticipant @clogs]

Tractor man,

why do u want to know which direction the wind comes from……..thought most wind turbines even small un's follow the wind by themselves…..u can't keep turning the thing by hand to keep it facing into the wind…….or have I got the wrong end of the stick……?

also, bear in mind wind speed and having the ability to shut it down in a storm…….

sorry……..clogs…..

[SamsarandaParticipant @samsaranda]

Clogs I think he means a weather vane, not a wind turbine.

Dave W

[MuzzerParticipant @muzzer]

If you are comfortable with electronics and Arduinos, you could fit a simple position encoder and run a small cable up to the vane. If you aren't into all that, perhaps a flexible (Bowden style) cable would allow you to bring the vane orientation into the house without having to drill holes in the roof and ceiling.

Even simpler, buy one of those wireless weather centre things and doctor the wind direction sensor to fit your weather vane. A spare sensor is a tenner, so you could hack it about without risking the bank.

Murray

Edited By Muzzer on 23/12/2017 14:34:45

[JourneymanParticipant @journeyman]

Used to have one of the Maplin style weather stations. Software not too good but there are better free on the web. Lasted just over a year before the anemometer packed up. Wiring up is a bit finicky if they still use the telephone style connectors, needs better waterproofing than supplied with.

John

[Sam Longley 1Participant @samlongley1]

Tick Tack Wifi wind speed & direction plus solar powered masthead ( chimney)unit—–http://www.cactusnav.com/files/tacktick%20brochure.pdf

I suppose if you wanted to make your own wifi is the way to go but you need to be an electronics wizard first

[egaParticipant @ega]

Journeyman:

I have one of those which has stopped talking to the internal weather station. Did you find a satisfactory replacement, please?

[JourneymanParticipant @journeyman]

ega, I gave up with it eventually after a couple of replacement wind vanes and anemometer. I decided that it was easier to use METAR if I really wanted the information being only a few miles from Heathrow (EGLL) their system is always on-line. I think for reliability you need to look at something like the Davis weather stations but they are a bit spendy!

Last useful bit of software I used was *** Cumulus *** by Sandaysoft which is still being developed.

John

Edited By Journeyman on 23/12/2017 16:09:26

[egaParticipant @ega]

Journeyman:

Many thanks. I might look at a simple rain alarm, rain being my interest at the time I bought the Maplin device.

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by Journeyman on 23/12/2017 16:01:46:

Last useful bit of software I used was *** Cumulus *** by Sandaysoft which is still being developed.

I've been using Weewx software for over four years now. It runs on Linux and MacOS. I am running it on a Rasperry Pi and the result can be seen here

Russell

[SillyOldDufferModerator @sillyoldduffer]

My thoughts would go to an electronic solution first. Then the vane, bearing and support could all be small and easy to make, with easy to run wires carrying the data.

If a mechanical solution is preferred, the vane, bearing and support will have to be bigger. More weight and friction. But rather than running a heavy shaft down to floor level and providing a gearbox, I'd try a bowden cable.

Of course the whole point of having a mechanical vane might be because it's an attractive novelty. In which case, a thrust bearing at the bottom of a scaffold pole to take the weight with a collar bearing at the top to keep it vertical. The vane would be fixed directly to the top of the pole and the whole pole allowed to rotate. At the bottom a pair of 1:1 gears to transfer the drive into the house.

Dave

[Tractor manParticipant @tractorman]

Yes it’s a wind vane rather than a turbine.
Any I want it to be a feature rather than just functional.
Dave, I have been sketching away and have come up with just the thing you suggest. I’m making a half scale mock up to test the theory but it will basically be a bearing tube with roller bearings to hold the shaft and a thrust bearing to take the vertical load.
I will try to knock up a drawing I can post here for comment.
Just a crazy project to occupy me and Grace the house. We live on top of a hill and get all the wind we need, I put up an outdoor clock and passers by always comment on how good it looks. I hope the wind vane will be the same.

[vintagengineerParticipant @vintagengineer]

The blacksmiths way of making weather vane bearings is solid rod at the top with a loose fitting tube on the vane. When you put the vane over the upright you put two marbles up the tube and these act as the bearing.

[BazyleParticipant @bazyle]

The main thing is first an outer shroud tube at the top that rotates with the inner but comes down over the bearing tube. Adjust clearance to be enough to avoid capillary action pulling water up but small enough to stop spiders crawling up.

For the down runner to keep it light look into fibreglass tent poles, fishing poles, electricians threading rods.

A real mechanical one is way better than an electric gizmo. I've often thought it would be nice to run one down a spare chimney flue but then worry about the lightning risk in my exposed location.

[Tim StevensParticipant @timstevens64731]

If you can find a position in a room that is directly below a mounting point for the vane itself, a simple plain wire could transmit the information. As used in older car choke pulls – not as flexible as a Bowden but stiffer in a rotational sense (which is what you need). At the room end a small mirror at a angle, with eg a laser pointer aimed at it, and the wind direction could be displayed across the ceiling. the idea is to keep the driven parts (below the vane) as light as possible, reducing loads on bearings, etc.

If you have difficulty finding a wire which is straight enough, take a length rather longer than what you need, trap one end in a vice and pull hard on the other end so that you put a permanent small stretch in the wire. Then cut the (damaged) ends off and the middle bit should be carried carefully to where it is needed. This will certainly work unless the wire has been seriously bent and straightened before, as this will work harden some sections more than others, and the stretching trick relies on an even stretch over the whole length.

And if you need a sleeve to carry the wire, use a modern motorcycle Bowden outer, lined with Teflon.

Hope this helps

Tim

Edited By Tim Stevens on 26/12/2017 15:23:28

[Nigel BennettParticipant @nigelbennett69913]

My friend's father built himself an anemometer (rather than a wind direction indicator) many years ago. He was amazed to discover from his recording instrumentation that there had been some massive wind gusts, apparently of a hundred miles an hour or so.

My friend didn't have the heart to tell him he'd been blazing away at the anemometer cups with his air rifle…

[pgk pgkParticipant @pgkpgk17461]

Authentic style weather vane needs a good squeak when it turns..

[Neil WyattModerator @neilwyatt]

If you have a straight drop, then a long rod in an oversize tube with a bearing at each end will work. A simple bevel gear will allow a vertical dial.

The bigger the vane the more sensitive and able to overcome friction it will be. It doesn't have to be huge.

Someone I know has 3D printed one that uses a magnet and a compass sensor. She incorporated an aluminium disc and two powerful magnets to provide damping without eliminating sensitivity.

Neil

[Tractor manParticipant @tractorman]

Neil. The magnetic damped disc sounds interesting. I assume two aluminium discs with magnets are the key but can you explain further?
I hope to be able to drop straight down from.tbe ridge line to the central wall where I will site the dial. The bevel drive has to be carefully planned so that rotation is correct.,the vertical shaft gear must be below the dial shaft to ensure proper direction of rotation for the pointer.
Regards

[Frances IoMParticipant @francesiom58905]

I presume the aluminium (or any conductor) disk rotating between the N-S poles of a magnet acts as a single turn armature, the current induced varying with the speed of rotation- wch current also then acts as a motor current wch would turn the armature in the contrary direction thus giving a damping effect that varies with the speed

[Peter KroghParticipant @peterkrogh76576]

A simple eddy current brake. The ready availability and low price of Neodynium magnets has made such dampers easily affordable for us to play with. I love thinking about some new gadget to mess with…..

Pete

[Tractor manParticipant @tractorman]

So applying the principle of an eddy current brake to the indicator pointer, I would attach a non ferrite disc to the pointer shaft behind the dial and place two strong magnets either side of the disc. Would this provide an eddy current effect at the low speed of the pointer shaft i.e. damping sudden changes in direction of the vane in the roof? Would the use of kilopoise lubricant in the pointer shaft be a similar method of damping such movements? Mick

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Peter Krogh on 27/12/2017 07:26:50:

A simple eddy current brake. The ready availability and low price of Neodynium magnets has made such dampers easily affordable for us to play with. I love thinking about some new gadget to mess with…..

Pete

.

I had only thought of pemanent magnet eddy current braking in lightweight applications, before … and was astonished to see Circular Saws and Roller Coaster Rides mentioned on the Wikipedia page: **LINK**

https://en.m.wikipedia.org/wiki/Eddy_current_brake#Disk_eddy_current_brakes

Always good to learn something new

MichaelG.

[Author]

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