Topic: VP2 tipping spoon raingauge?

[DRoberts]

CoCoRaHS:             .83" last 24 hours
VP2 Tipping Spoon:  .83" last 24 hours

Wind East gusting to 30 at times.

[drew1021]

Single spoon replaced tipping bucket on VP2 yesterday afternoon. No problems with the replacement.

Mother nature cooperated for a change and we actually had a nice rain yesterday evening.

Comparison:

CoCoRaHS .32"
Tipping spoon: .30"

Distance between the two gauges is about 20 feet.

Just thought I would share.

Are they the same height?

[openvista]

I'm also seeing extremely close results. We had a large weekend rain event.

CoCoRaHS (4' AGL): 2.67"
VP2 Tipping Spoon (6' AGL): 2.70"

The two gauges are 6' apart from each other.

I did notice in an earlier event that the CoCoRaHS gauge caught 0.15", while the spoon only collected 0.13". That first 0.01 or 0.02" may not get recorded if the rain is comprised of smaller droplets falling lightly. Seems they get caught in the debris screen?

FYI, I also switched out the rain cone to the newer Aerocone.

[dport]

This is almost enough evidence for me to go out and "upgrade".  Thanks to all who have posted results.  Keep em coming. 

[JudinNorman]

I'm not convinced yet. I'd like to see a years worth of data in a wet environment. Burt over in UK hopefully does a study.
My rainwise has been going good for close to 20 years

[drew1021]

I'm not convinced yet. I'd like to see a years worth of data in a wet environment. Burt over in UK hopefully does a study.
My rainwise has been going good for close to 20 years

Agreed, way too soon to come to conclusions on accuracy. One would need to compare and record data over a year as you mentioned. So far I suspect there is a slight positive bias based on my 3 weeks of observations. As far as waiting to purchase I say go ahead and buy and have fun observing.

[WheatonRon]

This is almost enough evidence for me to go out and "upgrade".  Thanks to all who have posted results.  Keep em coming.

Here are my thoughts on the new Davis rain tipper after several rain events since I installed the new spoon tipper in one of my 3 VP2s. I also have a CoCo gauge that I use for comparison purposes. Some of my results I previously posted in this thread, other results were not posted, as the results were directionally consistent with my prior results. In short, the spoon tipper appears to be a slight improvement over the dual tipper Davis replaced it with. My issue is cost. Personally, I think the new tipper is probably worth an upgrade price of about $30-$40, not the nearly $60 I paid Ryan at Scaled Instruments and his prices are the best. Davis probably thinks it has hit a home run and fixes the notoriously inaccurate VP-2 rain gauge—not so—better accuracy yes, maybe a single but certainly not a home run.

[DRoberts]

Single spoon replaced tipping bucket on VP2 yesterday afternoon. No problems with the replacement.

Mother nature cooperated for a change and we actually had a nice rain yesterday evening.

Comparison:

CoCoRaHS .32"
Tipping spoon: .30"

Distance between the two gauges is about 20 feet.

Just thought I would share.

Are they the same height?

VP2 is 1 foot higher than CoCoRaHS

[drew1021]

Another update:   Overnight, moderate showers came through with no wind with the following results.

Stratus.        .47
VP2.        .50

I'm convinced that there is a positive bias with the new spoon assy. I have another spoon assy that I've calibrated to tip at precisely.544ml/per tip using a medical grade syringe. I'm going to install today. By the looks of the extended forecast  I may be waiting awhile for results.
BTW, both spoon assy's initially tipped at around .50ml

[DRoberts]

Additional data on VP2 spoon:

Series of rain/thunderstorms last night (26-27 May) with occasional gusts to 30, but primarily just light winds. Rainfall ranged from light to heavy.

CoCoRaHS gauge: 1.47"
VP2 Spoon: 1.49"

Just FYI

[WheatonRon]

Today’s rain event that lasted 1hour and 15 minutes. Shortly after noon.

Gauges about six inches off the ground—no fence or trees nearby on solid support (gauges within 10 inches of each other):

CoCo gauge 1.50 inches
VP2 with new tipper 1.53 inches
VP2 with old tipper 1.55 inches

VP2 with old tipper on a fence post about 6 feet off the ground, some trees nearby—1.20 inches—about 30 feet away from above gauges.

Conclusions? I am confused, but pleasantly surprised with the VP2s by the CoCo gauge.

[Bunty]

So how do you remove the old tipping buckets without breaking something?   Posts in reference to it sounded vague, so I gathered it's pretty much self explanatory by looking at how it's mounted, and so it the installation of the new  tipping spoon.  Are any tools required?

[CW2274]

So how do you remove the old tipping buckets without breaking something?   Posts in reference to it sounded vague, so I gathered it's pretty much self explanatory by looking at how it's mounted, and so it the installation of the new  tipping spoon.  Are any tools required?

All I remember is that it was a pain getting it out without fear of breaking it. I'm fairly sure I merely pried it out with a flat blade screw driver, but the prongs took it as nothing broke. Using a lube was suggested, may be reasonable. No idea about how tough installing the new one is though.

[drew1021]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

[drew1021]

Another update:   Overnight, moderate showers came through with no wind with the following results.

Stratus.        .47
VP2.        .50

I'm convinced that there is a positive bias with the new spoon assy. I have another spoon assy that I've calibrated to tip at precisely.544ml/per tip using a medical grade syringe. I'm going to install today. By the looks of the extended forecast  I may be waiting awhile for results.
BTW, both spoon assy's initially tipped at around .50ml

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

[WheatonRon]

So how do you remove the old tipping buckets without breaking something?   Posts in reference to it sounded vague, so I gathered it's pretty much self explanatory by looking at how it's mounted, and so it the installation of the new  tipping spoon.  Are any tools required?

Davis does not include any instructions. First, remove the rain collector from the rainbase, disconnect the wire connecting the tipper to the PCBA. At one end of the old tipper there are two plastic pegs that need to be moved (pushed forward) slightly so that the tipper can be dislodged from the rainbase. At the other end, the tipper fits into two slots in the rainbase. It is pretty obvious how to do this procedure once you have the rainbase in front of you. Using a flathead screwdriver can help you pry those plastic pegs so the tipper can be dislodged. Take some time, study the situation with the rainbase in front of you and you should have no problems. You don't need to take the ISS down--I found it easier that way. However, you need to see what you are doing so if the ISS is too high, you might be better off taking the ISS down.

Attached is a photo of the old tipper that has been dislodged from the rainbase showing the pegs or tabs on the right that need to be pried to loosen the old tipper. The slots I referred to are visible on the left side of the photo.

 [ You are not allowed to view attachments ]

[DRoberts]

So how do you remove the old tipping buckets without breaking something?   Posts in reference to it sounded vague, so I gathered it's pretty much self explanatory by looking at how it's mounted, and so it the installation of the new  tipping spoon.  Are any tools required?

Davis does not include any instructions. First, remove the rain collector from the rainbase, disconnect the wire connecting the tipper to the PCBA. At one end of the old tipper there are two plastic pegs that need to be moved (pushed forward) slightly so that the tipper can be dislodged from the rainbase. At the other end, the tipper fits into two slots in the rainbase. It is pretty obvious how to do this procedure once you have the rainbase in front of you. Using a flathead screwdriver can help you pry those plastic pegs so the tipper can be dislodged. Take some time, study the situation with the rainbase in front of you and you should have no problems. You don't need to take the ISS down--I found it easier that way. However, you need to see what you are doing so if the ISS is too high, you might be better off taking the ISS down.

Just replaced my VP2 tipping bucket with the "spoon" and did it exactly as above. Study the way it is connected and be careful of how rough you are in removing the bucket from the two tabs.

[lightmaster]

I installed the single spoon last week, and it definitely has a specific orientation. The draining part has to face away from the transmitter box.

[WheatonRon]

I installed the single spoon last week, and it definitely has a specific orientation. The draining part has to face away from the transmitter box.

While your statement is correct, I believe there is only one way to install it. The tabs will work correctly only on one side.

[lightmaster]

I installed the single spoon last week, and it definitely has a specific orientation. The draining part has to face away from the transmitter box.

While your statement is correct, I believe there is only one way to install it. The tabs will work correctly only on one side.

Yeah, the tabs will only work one way. I was just putting that out there for anyone that had trouble and didn't think to rotate it. There are no instructions with it and some people out there need explicit instructions to install things.

[Jester]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

Ok Drew, how did you calibrate?

[drew1021]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

Ok Drew, how did you calibrate?

Looking underneath the spoon, locate the stainless steel screw. You'll notice that there isn't a notch to fit a flat blade screwdriver, and it will have locktite on it. This is where it gets a little tricky as you will have to get needle nose pliers and grasp the threaded portion of the screw firmly and turn clockwise to increase the amount of tips and counter clockwise to decrease. So in my case I was experiencing a positive bias so I turned it counter clockwise slightly. I tested after calibrating using a 10cc medical grade syringe to tip at around 5.4cc. If someone knows of a tool to use to turn the screw let me know as I dont like using needle nose pliers to do the job. As far as I can see it's the easiest way without disassembling the entire spoon assy. Hope this helps.

[twcmaster]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

Ok Drew, how did you calibrate?

Looking underneath the spoon, locate the stainless steel screw. You'll notice that there isn't a notch to fit a flat blade screwdriver, and it will have locktite on it. This is where it gets a little tricky as you will have to get needle nose pliers and grasp the threaded portion of the screw firmly and turn clockwise to increase the amount of tips and counter clockwise to decrease. So in my case I was experiencing a positive bias so I turned it counter clockwise slightly. I tested after calibrating using a 10cc medical grade syringe to tip at around 5.4cc. If someone knows of a tool to use to turn the screw let me know as I dont like using needle nose pliers to do the job. As far as I can see it's the easiest way without disassembling the entire spoon assy. Hope this helps.

Just to be sure, you are referring to the new single spoon assembly? And the stainless screw with no notch is the one that looks like it is the bottom of a screw sticking up from the plastic?

[drew1021]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

Ok Drew, how did you calibrate?

Looking underneath the spoon, locate the stainless steel screw. You'll notice that there isn't a notch to fit a flat blade screwdriver, and it will have locktite on it. This is where it gets a little tricky as you will have to get needle nose pliers and grasp the threaded portion of the screw firmly and turn clockwise to increase the amount of tips and counter clockwise to decrease. So in my case I was experiencing a positive bias so I turned it counter clockwise slightly. I tested after calibrating using a 10cc medical grade syringe to tip at around 5.4cc. If someone knows of a tool to use to turn the screw let me know as I dont like using needle nose pliers to do the job. As far as I can see it's the easiest way without disassembling the entire spoon assy. Hope this helps.

Just to be sure, you are referring to the new single spoon assembly? And the stainless screw with no notch is the one that looks like it is the bottom of a screw sticking up from the plastic?

Yes and Yes

[twcmaster]

Okay, results after calibrating spoon assy are as follows:
Moderate to heavy showers came through last night with light winds,

Stratus.        1.02
VP2.      1.02

Ok Drew, how did you calibrate?

Looking underneath the spoon, locate the stainless steel screw. You'll notice that there isn't a notch to fit a flat blade screwdriver, and it will have locktite on it. This is where it gets a little tricky as you will have to get needle nose pliers and grasp the threaded portion of the screw firmly and turn clockwise to increase the amount of tips and counter clockwise to decrease. So in my case I was experiencing a positive bias so I turned it counter clockwise slightly. I tested after calibrating using a 10cc medical grade syringe to tip at around 5.4cc. If someone knows of a tool to use to turn the screw let me know as I dont like using needle nose pliers to do the job. As far as I can see it's the easiest way without disassembling the entire spoon assy. Hope this helps.

Just to be sure, you are referring to the new single spoon assembly? And the stainless screw with no notch is the one that looks like it is the bottom of a screw sticking up from the plastic?

Yes and Yes

Excellent, thank you for sharing! Mine has a major negative bias, but I was still afraid to mess with that screw.