Oh, do you want this calculation?
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
You need a known start point. And that is the original Oregon resolution. A tip based on a 10 cm diameter area (78.53 cm2) is 1 mm. Use these data as your “old” data with the second Niko’s calculator. The first one is not valid.
Actually all those calculators are wrong, back to the drawing board :oops:
At the risk of causing more confusion…
In going from a 100mm diameter to a 200mm diameter you doubled the diameter.
If you multiply the diameter by 2 you change the collecting area by 2 x 2 = 4. So with 4 times the area each tip will be caused by 1/4 = 0.25 as much rain as with no modification.
If you increase the original 100mm to 310mm, you have increased the collecting area by 3.1 x 3.1 = 9.61. With 9.61 times the area each tip will be caused by 1/9.61 = 0.104 as much rain as with no modification.
Does that make sense?
Oh dear Niko pmsl… not to worry…
Hi skyewright, thanks for joining in 
To answer your question “Does that make sense?” not really cause my original is 113.5 :?
skyewright that’s exactly right 
The calculators agree now too, sorry about that, never did a php calculator before :lol:
Couldn’t resist. 
Are you sure? I thought the inside diameter of an unmodified WMR928 rain gauge was 100mm.
Are you using something else?
I was going by what the book says, so that must be the outside diameter then?
That’s what that figure it sounds like to me.
Maybe you could do a rough check by holding a ruler against your gauge?
Not precise, but it should at least indicate which figure is more likely.
Not possible to measure it anymore the modifications prevent that 
I will go by your measurement of 0.104 that certainly sounds about right to me
Thanks for your help, you to Niko and you three Breitling, appreciated guys 
Yes, that’s exactly the math to do.
Thanks for the confirmation Breitling
At least i now have this bookmarked for future reference
Hi all !
Very interresting topic !
I’m currently using a 0.43mm tip resolution with my wmr928nx.
Based on this discussion :
http://discourse.weather-watch.com/p/217209
Here’s my actual installation (i’m currently testing the accuracy of this assembly
The funnel (15cm diameter)
Final assembly
Wish my mod was as clean as yours lol, damn glue gun
Niko, heres that thread where kve has a 0.16 tip and hes doing ok so
i can see there being too much of an issue with mine, but like i said, if
there are any i will just take off the top bowl and go back to the 200mm
Albeit i aint sure what the counterweight does :?
I’m just concerned that in a real downpour there will be so much water going through there that it can’t tip fast enough to measure correctly and will under-report, but hey, this is all about experimentation so why not
Will find out soon enough, supposed to be some rain tomoz, will see.
I have a manual bucket that i made up myself yesterday (from the met office)
its not 100% perfect but it will give me a fair comparison to work with, i will let
you know how it goes
Since yesterday we have had a total of 6.7 mm Some was heavy late last night
cause of the bad wind (was banging on the window anyway lol) anyway, i just
checked the manual gauge and it was between 6mm and 7mm. I only did 1mm
increments and it was hard enough doing them lol but from what i can see its
working ok at present.
I suppose it really needs a good downpour to get a proper idea so i will report
again whenever that happens
Cool
I think max tips/min is in the specs. Somehow 99 is a figure that springs to mind.