Home made sling hygrometer

[legin]

Hi All

I thought I would make a sling hygrometer as I do not trust my cheap dial ones.
The thermometers cost $2.50 from the $2 shop. (did I get ripped off?) and the rest is from around the shed.
I just taped the thermometers to a piece of pine. Maybe I will fix them on a bit better later.
Drilled a hole for a piece of 6mm steel rod into the board and tapped the rod in tight.
Then a slightly oversized hole into the handle so it spins easy.
The wick is just a piece of shoelace.

5 bucks!!

I did my first reading today which was wet bulb 21 deg, dry bulb 28 deg - 51% humidity
I am having trouble finding a decent chart with a temp range over 30 degrees. I definitely get temps over 30 degrees here in Perth so if anyone has a chart that would be great.

My other dial hygrometers say 70% and 62%. I might try the saturated salt in the lunchbox with them and see what they read.

Please excuse the crappy mobile phone photos.

[Steve.Toscano]

Thats one way....

I have 4 sub $10 hygrometers from jaycar.
They sit on the same shelf in the workshop and they all give different results ( although usually all within ~5%). I just average them out
Oddly the one in the group that reads low one day can read high the next day and vice versa.

[garryalb]

Hope you can read this, just a photo. A simple chart is available at fccj.us

Garry.