Davis VP. My anemometer cups fell off.

[maxen]

First I have to say Hej to everyone here. I think this is my first post here.
I am quite new to Weathercat, but have been using other softwares for my Vantage Pro over the years. I live on the south west coast of Sweden, near a city called Halmstad. "My" weather is found online at http://vader.vilsharad.net

Now, during a quite hefty storm the last week end my VP suddenly stopped registering the wind speed. In the morning I found the anemometer cups on the lawn. Earlier this summer they also fell of, during a warm not-at-all windy day. That time I just put it back and tightened the screw. Obviously this did not work all ok.

Now I am not sure if the cups are missing something? There is a magnet, placed horizontal in the cups, but also a hole that is now empty, right beside the hole for the axle. It looks like there has been something there (a counterweight??) If the cups-unit is not balanced it might explain why they vibrate and fall off. But what do I know?

The cups now looks like this (see below). I have not been able to take the rest of the anemometer down since it is all dark when I come home from work. I will look into it the next week end.

My VP has been in service for 11 years so the plastics in the ISS is starting to look somewhat worn. But if I can get the anemometer fixed I think it can postpone buying a whole new station - at least for a while.

Best regards

[wurzelmac]

Hi maxen,

no idea about your anemometer issues, but
welcome in this forum!

Cheers,
Reinhard

[LesCimes]

Hi Maxen,

Welcome to the forum!

I have had my anemometer apart on a couple of occasions, though it has been several years ago. If my memory serves me correctly, there is nothing missing in your anemometer. there is a reed switch on the housing that responds to the spinning magnet. In any case, you could email the picture to Davis Instruments tech support and I'm sure they would determine if there is something missing.

Fun to have another nation represented on the forum.

[xairbusdriver]

Welcome AboaRd, Maxen!

My station is not yet even 11 months old! Nice to know it could last another 10 years! On the other hand, it may just be that the set screw is loose. Is it still there? Is there still a 'drip shield'? Does the metal shaft look worn, especially where the set screw would be?

I assume that any bearing is on the shaft, up in the main housing. After 11 years of turning, it may well be worn, which could be the cause of the vibrations.

I'm assuming that the cup hangs from the bottom of the wind vane mount. <This page> explains what I'm talking about for the model that has been in use since 2003. (Frankly, I can't see any difference in the two images or instructions ) I notice there is a note about NOT lubricating the shaft... I hope I can remember that...

The US price is only $15 for a new set of cups, set screw, and drip shields. I think Davis has suppliers in England? At any rate, replacing the old ones will give you some bright shiny ones that might run more smoothly!

[elagache]

Dear Maxen and WeatherCat welcoming committee,

First things first, Welcome to the WeatherCat forum!

Now, during a quite hefty storm the last week end my VP suddenly stopped registering the wind speed. In the morning I found the anemometer cups on the lawn. Earlier this summer they also fell of, during a warm not-at-all windy day. That time I just put it back and tightened the screw. Obviously this did not work all ok.

Unfortunately, I had no luck locating a Vantage Pro anemometer cup.  They might still be out there.  Certainly contacting Davis technical support is one option.

I did find that Scaled Instruments sells a complete anemometer replacement that works with both the Vantage Pro and Vantage Pro-2 lines:

https://www.scaledinstruments.com/product/davis-6410-anemometer-for-vantage-pro2-vantage-pro/

If the rest of your anemometer is looking worn out and the other instruments look okay, perhaps that wouldn't be such an unreasonable investment to extend the life of your current station.

Even if I didn't see the anemometer cups that you need, you might send an email to Ryan Wilhour the proprietor of Scaled Instruments.  He is a very nice fellow and has helped me and several other WeatherCat users get their Davis stations repaired after calamities.  The email information is on this webpage:

https://www.scaledinstruments.com/contact-us/

Welcome once more to the WeatherCat forum and best of luck in getting your weather station back up to normal operation!

Cheers, Edouard 

[Blicj11]

Maxen :

Welcome to the WeatherCat forum.

I agree with Edouard's suggestion that you email Ryan at Scaled Instruments. On more than one occasion he has been extremely helpful to me and often has more helpful insights than Davis Tech Support.

[maxen]

Thank you for the warm welcome and help, guys!

I have e-mailed my question about the hole/magnet to Davis support. I'll start there and see if I get som answer. Buying spare parts directly from US is usually (and sadly) not an option here due to shipping costs and import taxes.

I took the little device to work and all bits and pieces seem to be there. BUT I now found a very tiny crack in the plastics, about 90deg from the fixation screw.
This probably makes the plastic flex just enough for the whole cup holder to fall off. Also one of the cups itself were a little whiggly due to this. I filled the tiny crack and fixated all three cups with a wicking* glue.

No matter what I will take the rest of the anemometer down in the week end to check how the magnet works and try to remount the cups. I'm thinking of trying a drop of thread lock on the axle before putting it back on to help it keep in place. I'll keep you posted.

(* I have no idea if this is the right word. Had to use google translate here. )

[xairbusdriver]

I have no idea if this is the right word. Had to use google translate here.

Sounds like a good translation! I suspect your English is better than Google's, anyway!

Many plastic glues are very low viscosity, they flow like water into a tiny crack. There are also Cyanoacrylate adhesives that can have extremely low viscosity. Either type may work on the hairline cracks you found, that's one of their best uses.

If the plastic shows a slight softening when a drop is placed on a non-critical part, that plastic glue would work. If the plastic shows no effect (softening), the Cyanoacrylate adhesive may be best.

Either way, a crack running into the set screw area could well cause the screw to lose its effectiveness and allow the cup assembly to fall off. Using some 'thread lock' will probably also help, however, it may also make it nearly impossible to ever replace the cup assembly. For example, if one cup breaks off (hail, bird strike, etc), it could be extremely difficult to get the hub, with the other two cups, off. There are some 'thread lock' brands that also make an 'unlock' chemical. Be sure to use that brand/type.

One more thing to verify is that the hole in the main, center body of the cup assembly has the same shape as the shaft. I'm pretty sure the shaft has a flat area on one side. In other words, looking at the end of the shaft, it should have a "D" shape, same for the hole on the hub. If the hole is rounded, it will be depending entirely on that set screw being extremely tight since it won't be touching the flat part of the shaft. That worn hole could also cause the vibration as the assembly could be off center.

I understand the shipping costs problem. I was hoping that some of our European members would come along and mention the suppliers on your side of the Pond (Atlantic). I'll do a search here, I'm almost positive I seen a company mentioned...

[xairbusdriver]

Parts, info a bit closer to Sweden:
<This post> mentions some dealers/suppliers in England. Also found <this link> to McMurdo Group, the Davis distributer (for Europe?), this may be who you've already been talking with.

[maxen]

Great info, Xairbusdriver! Thanks alot!
I used a extremely low viscosity cyanoacrylat glue we have at work. I small drop and is was immediately "sucked" up into the small crack. I hope it will hold together.

Good point about the D-shaped shaft. I will probably take the whole anemometer down and look it over in my small workshop to examine the status of it all. Maybe it is possible to change the reed switch at the same time, just in case. I guess it is overdue its lifetime and expected number of operations. I just cant find any instructions how to disassemble the unit.

I do not feel I want to spend a lot (or any!) big money on this weather station due to its age and overall condition of the outdoor unit. I just try to keep it running as long as possible. If plastic parts start to break (and is non-fixable thus requiring new parts) I am more leaning towards a whole new VP2 as replacement.

Take care!

[xairbusdriver]

I am more leaning towards a whole new VP2 as replacement.

My wife has made similar comments...

Oops! That "D" shape is on the wind vane! Disregard any ererz eye maik! The cup shaft is probably just round. Still, if that shaft show scoring, it probably means the set screw was slipping. Seems like a drilled hole in the shaft and a small bolt and nut would be sturdier and take care of the possible height adjustment error they mention, not to mention cheaper to manufacture.

[maxen]

Hi
So I got reply from Davis: there should be nothing in that hole. Good news.

I managed to get home a bit early from work Thursday and Friday this week, so I had a few minutes to go up on the roof, before it got all dark around 1600h.

It was noticeable that I have not done any maintenance on the anemometer over the years. (The ISS I take down, disassemble, clean and make nice once a year, but the anemometer is normally a bit hard to reach.) Anyway, after all these years the wind vane was a bit squeaky and tacky.

Reed switch looks good. By measuring ohms, it is doing what is should, and is probably in series with a 100ohm resistor for protection.

So all I did Thursday night was to clean all parts real good, use some contact clean/lubricant spray very sparingly around the potentiometer's axle, polish the plastic parts (same paint protection I use on the car), put the cups back with a tiny drop of silicone and the screw. All seem to work just fine. Try to find the anemometer in picture below, showing my crowded little workshop after the work was done.

On Friday, after work, it was just to take it back up on the roof, connect, take a tranquil photo and enjoy.

EDIT: Well, I guess one should be happy after the storm in question. Only a small anemometer that could be repaired and a few trees around the house that was needed to take down. It could be way worse.
http://www.thelocal.se/20151130/storm-gorm-leaves-trail-of-devastation

[xairbusdriver]

Great! Hope this is the last problem you have for another 11 years! I'd make one important change, however. I think you should add the "Davis" name on the wind vane (both sides, of course). I think it adds a bit of air friction that helps the vane point into the wind even with only a very slight air movement. On the other hand, if the shaft is not exactly vertical, the added weight will cause the vane to indicate the direction as the 'high side'...

As for your work desk top, if it isn't cluttered, you are not work hard enough!

[elagache]

Dear Maxen, Blick, X-Air, and WeatherCat station caregivers,

Glad you were able to get your station back into operation with minimal struggling! 

EDIT: Well, I guess one should be happy after the storm in question. Only a small anemometer that could be repaired and a few trees around the house that was needed to take down. It could be way worse.

Glad indeed that you had nothing more to repair considering the power of this storm.  We are now into late autumn and this is one of the two times of year when storms can be particularly severe.

On Friday, after work, it was just to take it back up on the roof, connect, take a tranquil photo and enjoy.

Thank you for the beautiful photo of your anemometer!! 

If you have any more photos like this, perhaps you could share them with us on this thread of photos of this sort:

http://athena.trixology.com/index.php?topic=1842.0

I am more leaning towards a whole new VP2 as replacement.

Even if your station dodged this bullet, you might want to start setting aside some money toward that eventual purchase.  The good news is that indeed you can wait, and Davis is definitely overdue with some sort of upgrade to the Vantage Pro-2 line if not a complete overhaul.  Perhaps your old station will hang on until Davis unveils something new.

Cheers, Edouard 

[Blicj11]

Glad to hear you are back up and running.