This kind of thing come up often enough, wouldn’t it be nice if someone wrote a little online calculator? It would take someone better with the math than I am.
- Jim
This kind of thing come up often enough, wouldn’t it be nice if someone wrote a little online calculator? It would take someone better with the math than I am.
I even tried doing a search for my other posts, can i hell as find it… #-o
Although that didn’t actually give me the answer as i settled for the .25 in the end
but yeah a calculator would be a great idea
It is very easy:
original section / new section = resolution
So: new section = orignal section / desired resolution
An example for your particular case:
Desired resolution = 0.1 mm
Original Oregon section = 78.5379 cm2
New section required= 78.5379 / 0.1 = 785.379 cm2
Section = PI * square radius; Radius = sq root (section / PI)
So you need a funnel of 15.81 cm radius. Or 31.62 cm diameter.
Edit: just a note on this. Take into account that you are letting so much more water inside, so the tipping mechanism can be easily overflown. The accuracy you’re looking for may become a big error.
Easy, yeah i can see that… :? lol
I do not understand the majority of that, maths is far from my strong point
But i thank you for the answer
Actually, i think i do sort of, in my cause all i needed to do was to move the decimal
so am i right in thinking the offset would be 0.1?
I don’t know exactly what you have done. This is what you need:
1.- Calculate the new section: divide funnel diameter by 2. Square it (multiplying by itself). Multiply by 3.1415
2.- Divide the old section (original Oregon) by the new section.
3.- The result is what you have to enter on WD.
Looks like i went the wrong way, it was more of a guess… #-o
So, with the sums done, i make the offset at 10. does that sound more realistic?
No, it is not an offset. It is a new tip volume.
Let me know the inner diameter of your funnel, I’ll do the math for you.
Just my personal opinion but I think that’s an unreasonable decrease in tip size. I wouldn’t be trying to push that amount of water through that coffee mug sized OS rain gauge.
Sorry Breitling it was the tip size i was on about, its cause its in the rain offsets is why
i kept calling it the offset :oops:
The internal Diameter is now exactly 31cm thanks Breitling…
i cut the darn thing down too much, so much for the 0.1mm, it cant be too far off though
I just want to give it a try Niko, see how it goes, if its too much then i will just remove it
It looks a bit ott i mist admit cause each stage i have made it bigger i just kept the older
one attached so it had the area for the new one to fit into, to its a 3 stage tower now lol
I also had to use a biggish flower container, finding a funnel was proving difficult for the size
wanted, so i went for something much bigger and cut it down…I aint attached it to the bucket
yet so no pics at present sorry, to be honest i dont really want to show it off either :oops:
hi Simon
0.1 is going to give you quite a few problems , as soon as you get moderate rain it will overwhelm the sensor
and give you incorrect rain readings
the lowest I have managed to get 0.25 tipping so far this is give me good results I would have fought there was a standard for the minimum tipping of most rain gauges Davies 0.2
I will be interested to see how you go on with this please send me some data back when you have some heavy rain
I would also put out a traditional manual rain gauge so you can compare results
mick
Its up and waiting for the rain now lol
If it does cause any issues then i will just remove it again, its was stuck down with
hot glue so thinners will easily dissolve the glue, dont care about the addons if they
melt a little i can just sand them down
I will certainly let you know how it goes, theres a manual weather station in Lidl later this week
could be now actually, i cant remember and i will get that to compare with
I thought davis was 0.1mm? oh well lol but i did read on here somewhere that someone did modify
to 0.1mm and it was running ok, just cant remember where i read it now…
I dont think its gonna be quite 0.1mm anyway as i cut it down too much #-o
Just need to tip size and im good to go
Good stuff Bashy, let us know how you get on (maybe a test pour with a jug?)
You really are the king of diy!
Thanks lol, you aint seen the image yet, attached below :oops:
A test pour never works out, i always end up doing too fast
But i will report the findings thats for sure…
Please dont laff, at least the top looks pretty :lol:
Looking at it i can see it getting blown off either Friday or Sunday :? :roll:
That calulator’s no good for thoughs of us with La Crosse raingauges, they’re square!! :lol:
Oh, I haven’t seen that model, they used to be rectangular :lol:
HI Niko, thanks for the link but witt me being as thick as i am
i aint got a clue what goes in the old tip and new tip :oops:
It’s the weather here, it alters their shape. :oops:
Thats better for me thanks Niko, but i still need to find what the original tip size is, is it 1.0mm?
Actually i went from my last modification
old mod 200mm new mod 310 new tip 0.16129032258065 does this sound about right?
I thought it would have been closer to the 0.1mm than that though.
cause the 200mm was @ 0.25