I decided to get the NovaLynx rain gauge calibration set along with the LCD counter.
The old calibration was showing 3-5% low with the 1/16" and 1/32" orifices.
I notice that there was as squeaking/scraping sound when the bucket tipped. It also seemed to take a long time to complete the tip. After reading several maintenance manuals, lubricating the pivot was recommended in several of them. One said not to lubricate for fear of dust getting into the oil. I could see this being a concern in the Southwest, but here in Northern Michigan I figure it shouldn't be a problem.
I could not believe the difference after oiling the pivot. The tip clunk was "quicker" sounding, and no scraping/squeak noise. The most surprising thing was that my calibrator results shifted to about 5% high or a shift of about 10%. I then made several adjustments until I was satisfied with the results.
I know that this rain gauge has a heavier aluminum tipping mechanism and metal pivot hardware. In this case, lubricating with "sewing machine oil" (borrowed from the missus) made a big difference in results. It will be interesting to see the results in future rain events.
Greg H.
