Topic: VP2 anemometer cups sticking

[SoCentralRain]

Hello everyone.  I'm new here, first time posting, so be gentle.

I've had my VP2 up and running since purchased new in May 2014.  That makes it 3.5 years old. 

From the looks of this thread, my dilemma is not uncommon--sticky anemometer cups.  Anything less than 10 mph and the cups abruptly stop.  After reading this thread, I felt emboldened to investigate a deteriorating anemometer bearing assembly.  Up on the roof I went, lowered the mast and had a look at my "patient". 

Sure enough, crunching sounds, a little grinding resistance.  So...I pull out my itty-bitty hex wrench of appropriate size to loosen the screw.  It fits snugly in the tiny hexagonal hole but won't turn!  More pressure on the wrench and...it's now stripped.     I have yet to try some lubrication in the screw hole, but that's about all I can do...

My questions:
-Am I going to have to replace the entire anemometer/wind vane assuming I can't get the damn stripped little screw to loosen? 
-If so, does the cable that leads from the anemometer/wind vane disconnect from the unit, or to I have to rerun the 50' of cable that travels all over my roof and gutter back to the main weather station assembly?

Anybody wish to chime in?  I'll happily pay for your two cents.   

Thanks in advance.

D.

[dalecoy]

Sure enough, crunching sounds, a little grinding resistance.  So...I pull out my itty-bitty hex wrench of appropriate size to loosen the screw.  It fits snugly in the tiny hexagonal hole but won't turn!  More pressure on the wrench and...it's now stripped.     I have yet to try some lubrication in the screw hole, but that's about all I can do...

My questions:
-Am I going to have to replace the entire anemometer/wind vane assuming I can't get the damn stripped little screw to loosen? 
-If so, does the cable that leads from the anemometer/wind vane disconnect from the unit, or to I have to rerun the 50' of cable that travels all over my roof and gutter back to the main weather station assembly?

Did the screw actually strip?  Or did the hex wrench (or the hexagonal hole in the screw) strip? 

The easiest solution would be to purchase a new anemometer, and use the existing cable - which will involve splicing the wire near the anemometer.  Otherwise, you're likely to have difficulty working, on the roof, to resolve the problem with the screw.

[johnd]

I'm guessing that you have the more recent 6410 anemometer design with a screw that holds the lower bearing assembly in place. If so, then you should be able to replace just the wind speed cartridge (and by the sound of it get some new cups at the same time). It will cost some, but substantially less than a new anemometer.

[dalecoy]

I'm guessing that you have the more recent 6410 anemometer design with a screw that holds the lower bearing assembly in place. If so, then you should be able to replace just the wind speed cartridge (and by the sound of it get some new cups at the same time). It will cost some, but substantially less than a new anemometer.

If he can get the screw out, and then replace it with a new screw that he purchases (perhaps needing to enlarge and re-thread the hole, or...) - while on the roof - or after taking the assembly off of the roof, including un-installing the anemometer cable, so it can be worked on more conveniently (and then re-installing it).

That partly depends on the damage to the screw, of course.  And it's quite practical, and less monetary cost, as you indicated.  And perhaps more fun.

[johnd]

If he can get the screw out, and then replace it with a new screw that he purchases (perhaps needing to enlarge and re-thread the hole, or...) - while on the roof - or after taking the assembly off of the roof, including un-installing the anemometer cable, so it can be worked on more conveniently (and then re-installing it).

Isn't he talking about the grub screw in the cups that's potentially stripped? If so then replacing the wind cartridge pre-fitted with new cups could probably be done in situ, subject to access of course. Just one large screw to remove and replace - in theory a 1-minute job (though not necessarily at the top of a ladder I know!)

[dalecoy]

Isn't he talking about the grub screw in the cups that's potentially stripped? If so then replacing the wind cartridge pre-fitted with new cups could probably be done in situ, subject to access of course. Just one large screw to remove and replace - in theory a 1-minute job (though not necessarily at the top of a ladder I know!)

Oh, maybe that's it.  I had not considered that possibility.  Of course, replacing the cartridge and the cup assembly would be less expensive, if that's possible.

[johnd]

Of course, replacing the cartridge and the cup assembly would be less expensive, if that's possible.

Well provided it's the more recent 6410 design with the demountable speed cartridge then it's trivial to do. But of course it does depend on the anemometer version.

[Intheswamp]

I agree about replacing the cartridge/cup assembly working if it's the latter anemometer design.  But, I wouldn't give up quiet yet...

Something else that might be tried is to spray a dot of Deep Creep (Seafoam product) into the hole where the grub screw is located and let it sit for several hours (a day would even be better).  Then, in one of those little micro screwdriver sets there is a screwdriver that can be tapped into the hex-hole of the grub screw. (I have never tried one of those little screwdrivers for this but there are usually so many of them that one of them has *got* to fit!  ).  Simply push the screwdriver against the grub screw and then tap it a few times to get it to go in a bit then firmly screw the grub out.  Having given the Deep Creep several hours to do it's magic, then with the jarring it receives as the screwdriver is tapped snuggly into it I've got to believe that the screw will come on out of there.  Deep Creep is not cheap, but it is very, very good at freeing up rusted and corrroded fasteners...I've seen it do some miraculous things. 

[piconut]

Another method for loosening the screw that has worked for me in a similar situation is to first find a small flathead screwdriver (or even a slightly oversized allen wrench) that fits squarely and firmly into the wallowed out allen wrench screw hole so that it doesn't turn at all.  Then put the tip of the screwdriver into an ice cube for about 5 minutes.  Then place the screwdriver back into the screw and let it sit for another minute or so to get the screw cold.  Then try turning it.  You will be surprised how a little "cold contraction" of the metal allen screw will work for being able to free up a stuck tiny allen screw that is wallowed out!  If you have a grocery store that carries dry ice, then this trick works even better!

[dalecoy]

That's all potentially useful information.  However, SoCentralRain asked the question (lacking a few details) over a day ago, and hasn't been back to communicate.

[Intheswamp]

Well, he might not be a real talkative type.     He'll probably be back before long.

[SoCentralRain]

Well, he might not be a real talkative type.     He'll probably be back before long.

Hi guys,

Actually, I'm quite the talkative type!  (Just ask my family!  )  I was away with family stuff (hospital visits are no fun) so I wasn't able to get back here to check on my inquiry.  I appreciate the responses!

Anyway, GREAT suggestions.  And yes, I'm dealing with the damn grub screw (I had no idea that's the name of this itty bitty screw--I must have not noticed when I installed it).  I'm keen to tackle it as soon as I can (it's evening here, and tomorrow's forecast calls for some rain, so...).

I'm going to try shooting a tiny drop of WD40 in there and letting that sit for a little while.  Next, I'm going to use a micro screwdriver to attempt what one of you suggested--getting it into the stripped hex nut as tightly as I can.  The suggestion of using a screwdriver that might be "cooled" with an ice cube or dry ice is interesting, but I don't know if there would be much effect given the ambient temperatures of 40 deg. F around here lately.  Also the trouble might be for me to get any leverage on the screwdriver while it's attached to the extension pole.  At least the roof I'm working on allows me to stand with decent stability. 

I'm saddened to hear that the complete anemometer/wind vane assembly is not easy to disconnect from the cable without splicing it--that's not the greatest design in my opinion.  Assuming I'm able to get the screw loose, I also hope to be able to remove the speed cartridge.

Again, thanks for the responses.  I'm pretty confident I'll be able to remove the anemometer cups as soon as I can get up on the roof to try.  I'll keep you all advised. 

D.

[Ian.]

I have replaced my 2013 anemometer today as the reed switch has failed.

I'll try and refurbish the old one by changing the reed and bearings, how do you get into the unit, does the body split?, how is it fixed together?

Update - Google was my friend http://www.cjoint.com/15ma/ECAj5A762FD_changement_ils.pdf

Update 2 - Removed the wind direction pot and reed switch assembly, how does the bearings come out??, any tips please.

[SnowHiker]

I have replaced my 2013 anemometer today as the reed switch has failed.

I'll try and refurbish the old one by changing the reed and bearings, how do you get into the unit, does the body split?, how is it fixed together?

Update - Google was my friend http://www.cjoint.com/15ma/ECAj5A762FD_changement_ils.pdf

Update 2 - Removed the wind direction pot and reed switch assembly, how does the bearings come out??, any tips please.

Maybe try this topic: http://www.wxforum.net/index.php?topic=28664.0

It may depend on how old your anemometer is, the older ones didn't seem to have an easy, nondestructive way to remove the bearings, as far as I could see.  Apparently they changed that in the VP2/brass tip era.

[Ian.]

Thanks SnowHiker,

I managed to get the bearing and brass follower out of the anemometer body, I wasn't sure if the bearing was flanged like some of the pictures others have posted and if it was, which way would it come out.

Looking at it again under a strong light, I couldn't see any lip and it turned out on my version it was simply an interferance fit, using a screwdriver and gently tapping allowed the bearing to dislodge into the body housing, to remove the brass follower I turned the body over and tapped this out.

I'll post up pictures of re-assembly when the new reed and bearing arrives.

[ocala]

Ya'll can all just call me "Speedy".    I just now have installed the wind speed cartridge (shaft and bearings assembly)...the prospect of Hurricane Irma arriving in two days encouraged me to "get'er done!".  The new cartridge appears to be working well.  Though folks south of me are getting plenty of wind it is rather becalmed around here right now so I haven't seen it clock any high speeds yet.  Tomorrow, and especially Monday, Hurricane Irma should give it a good test. 

As long as you have the allen wrench that came with the station or a set with some *small* ones in it and a medium size phillips screwdriver you have all the tools you need to work on it. Naturally you will need other than the tools to lower the mast with.  Simple repair....even "Speedy" did it. 

Observations:  I found that when I spin the stem of the old cartridge, with nothing attached to it and holding it in my hand, that the shaft/magnet(?) assembly will spin freely but suddenly "hit" something hard causing it to stop spinning.  Sometimes when it "hits" it will bounce back spinning a turn or two in the opposite direction.  It always "hits" when I spin it in the proper direction.  Oddly, when I spin it in the "wrong" direction, opposite of the design of the cups, it spins freely and doesn't "hit".  Also, if I hold on to the shaft and turn it while keeping my fingers on it (not simply free-spinning it) I can feel a rough scrubbing and it will lock up at times in either direction. 

I think something is inside that has "come lose", be it a ball bearing, a chip of metal, or ????, and it spins until that something jams the shaft or one of the bearings.  My old cartridge is not rusty or corroded and other than a small amount of spider web there wasn't any dirt or debris in it...it actually looks good.  It just suddenly stops when it when it "hits" that something. 

The new one seems to be working good, so hopefully it will be good to go for several more years.  The first cartridge lasted just a tad over four years.

I just thought I'd share what I did/found.

Best wishes to all, and to everybody in the path of Irma be safe.
Ed

ETA:  Link to the part needed... https://www.scaledinstruments.com/product/davis-6410-anemometer-for-vantage-pro2-vantage-pro/

Ed this is what seemed to have happened to mine. You can hear a slight grinding sound when it locks up. A strong enough gust will get the cups turning but eventually it binds up.
Kind of a bummer in that the whole thing was refurbished in July 16. Kind of thought I wouldn't have to do anything for a while. Also it's 32 ft up there on the antenna mast. I hate going up there.

[Intheswamp]

Did they list the cartridge as a part that was replaced?  I would bet that they didn't replace the anemometer cartridge.  Just because it's know to fail, why fix it when it ain't tore up, eh?    Maybe by us simply ordering a part in and not complaining to Davis they don't include the cartridge in their list of parts to replace in a refurb...BUT, they redesigned that part so they must know something problematical was going on with it. 

When you take it apart and see the little silver snap-ring washer then it's one of the original cartridges...if it's all encased in plastic it's the new model.

Sorry to hear you've got the problem.  I supposed you will be contacting Davis about the failed refurb???  Hearing how they respond will be interesting, too. 

Be *very* careful going up the antenna mast.  I've learned that I don't bounce like I used to and that my knees don't handle ladders as well as they used to, either. 

[noctilucent]

If I was in your shoes, I'd take some spray lubricant like silicone spray and some compressed air in a can and use the air to free any particulate matter and then shoot some lube in there before I tried disassembling the whole thing in the air, on a ladder, trying not to drop parts.  I took mine down, blew air through it and lubed it and it has been fine for almost a year now (and I still have a new set of bearings that I mistakenly ordered in case they ever stick up so much that they need to be replaced).  Either that, or bring the whole thing down to do the full repair because I don't think you'll be able to replace the bearings while on the ladder.  Just my $0.02.

In terms of removing the wind cups and applying silicone spray, it looks like you need to remove the cup assembly and then spray the silicone up into the bearings which are inside the head assembly, is that correct?  Is this where you need the tiny Allen key?  Mine is in a relatively inaccessible position and only having to climb up there once with all the right gear ready would be good.

Edited to answer my own question: There's a detailed install video showing you how it's done.  Looks like the easiest way to do it is undo the single Philips screw holding the cartridge and cups in place, then take them down and finish the rest on the ground.

[noctilucent]

Followup after replacing it: It was a really simple fix, as others have pointed out what you want isn't the (expensive) complete anemometer but just the (relatively cheap) 7345.953 wind speed bearing cartridge.  You can remove this, with the vanes still attached, in no time at all using a standard slotted screwdriver, then take it down/inside/wherever to do the rest.  The original, from a 2014 Davis, was pretty gummed up with gunk:

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The annoying thing is that while it appeared to be reading low, the extra leverage given by the vanes meant it turned easily when you tried to spin them, hiding the nature of the problem.  It was only when I took the cartridge down and removed the vanes so that you had to turn it by rolling the axle across your fingers that you could feel that it was like it was grinding through sand.  This is a coastal location so it had probably built up salt and other gunk, not helped by the design which isn't sealed at the top so all sorts of contaminants can get in from there:

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So if you're having problems with your wind speed readings, and in particular if you have an older Davis with the unsealed design, consider swapping out the wind speed bearing cartridge, it's a very simple fix.

[noctilucent]

A further update for people thinking of continuing with the original cartridge, I've cleaned it up a bit and flushed it through with CRC 5-56 (I keep a jerry can of it in the workshop so it was the readily available thing to use) to get all the gunk out which mostly restored normal operation, after flushing out quite a bit of black liquid it now spins freely but is still running rougher than the new cartridge.  Using a heavier oil than the CRC, which I was using mostly to flush out any gunk, will probably help but even then I think it'll just be delaying the inevitable, particularly since the unsealed top will allow new contaminants to get in.  So I'd say use oil as a stopgap until the replacement cartridge arrives, but don't rely on it unless you plan to clean and re-lubricate regularly.

[Eguraldia]

Hello everyone here

Last nite I noticed my wind direction on my VP2 has been "stuck" showing North 10 degrees..36 hours ago in the same position in this point

I went out this morning and yes,the vane is stuck...dont move at all even with winds of 35kms per hour( anemometer cups working fine)

 Checking the cabling between the ISS..and I cleaned the modular connector...looks everything ok so odviously the problem is the vane

I dont have access for a while to the roof so I dont know what to do...

[Eguraldia]

I have access to the ISS on the roof.From the ISS to the vane..another 5 metres so I went to the roof with a 5 metres of pieces of wood and just "shake" the vane...and yes...stuck!! now its ok... so I went to the console and..nothing changes ...the vane is not stuck now but the console ..already reset

[Eguraldia]

Some Update..

A while after "shake"the vane I went to check the console and in that moment(outside winds from NNE all day)...from North 10 degrees to 21degrees 358,325 etc but thats all....since,frozen... North 10 degrees only

[Eguraldia]

After few days nothing changes...North 10 degrees..just little changes from 10 to 6,7 degrees...but back to 10..

Today winds from NW...the vane is ok...time to buy new anemometer after 3 years.