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I am having a real hard time with it. Whats a decently accurate device and where can I get it?
Also any recommendations for humidifiers?
Thanks

Good luck on a gauge. I have two and they never read the same. One always shows 10% higher than the other.

I have a Venta LW44 humidifier. Really good unit from Germany. If you call them, they may have a refurb you could get for a good discount.

Ken

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http://www.casperguitar.com

Try a sling psychrometer. These are simple to make http://www.flinnsci.com/documents/demop ... s10301.pdf
A wet bulb hygrometer is basically the same thing. You just need good air flow in your shop.
Richard

I have two gauges, one showing 35% and one 60%...

Richard, Is that accurate? Pretty cool concept.

To my knowledge it is as accurate as you can get. Search this site for wet bulb hygrometer. There are a lot of discussions about it. After getting frustrated with the digi hygros I went to Lowes and bought 2 cheap outdoor thermometers . I hung them side by side took an old cotton shoe string and slipped it over the bulb of one of your thermometers (this is your wet bulb) and ran the string into a ziplock bag filled with water. I use this table and have it pinned beside the therms. http://www.novalynx.com/reference-rh-table.html

This is a good thread from Hesh
http://www.anzlf.com/viewtopic.php?t=2116

Good luck
Richard

The Caliber III is inexpensive and accurate. I have 4 and they all test alike with a calibration pack.

http://www.amazon.com/Caliber-III-Digit ... 203&sr=8-1
on sale for $12.35 at the above link to Amazon.com

Steve Brown

Steve,

You're lucky. My Caliber III as well as one of my customer's were 8 and 10 points low. The one I have that is consistently accurate against my wet bulb is a Radio Shack. Go figure.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

I tested a radio shack and a caliber III using the potassium carbonate test and both came out pretty dead on. Interestingly though the Caliber III seemed less accurate after the test while the radio shack just keeps on ticking.

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Burton
http://www.legeytinstruments.com
Brookline, MA.

Actually, the warranty on the Calaber III says it should not be tested with one of the test kits. My Calaber III is a piece of junk. It's always off. The best way it to go buy yourself an analog hygrometer, or a couple of them. Then get a wet / dry bulb thermometer. Check and calibrate the analogs every couple of weeks, using the wet/dry bulb thermometer. When I fill up the little vial of water on mine, it usually lasts a couple of days, and I just make sure the analogs are reading close to it, within a couple of points. I actually have two charts, that are slightly different in their readings, and I set one to the high reading and one to the low reading. As long as I'm in the range, I'm OK. I keep two fans running in my shop at all times, which helps keep the RH reasonably consistent all over the shop.

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Waddy

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Sound Clips of most of my guitars

Yep getting a decent hygrometer can be a long walk on a short pier with a lot of wasted money and effort but you can benefit from not making the same mistakes that some of the rest of us have made.

Edward I used a wet bulb test which is really the only way to accurately determine your current relative humidity to check some digital hygrometers and also to calibrate my Abbeon hygrometer. Wet bulb tests can be done with two like thermometers or a sling psychrometer, same idea.

I found my Caliber III's to be about 9 points off and more importantly in the range that we need to see RH wise, about 42 - 48%. What's interesting to note here is that if you test for accuracy say in the 50 - 60% range the amount that these digitals can be off can change. So checking the calibration of any hygrometer should be done in the range that you intend to maintain and not at say 75% with a salt test.

Waddy is correct that the instructions that came with the Caliber III indicate that a salt test can damage the unit. I am not sure if this is true or just a defensive measure to help prevent anyone from determining that these things are not much more accurate than a counting horse... with no shill to tell them when to stop...

What I use here works great for me but can be a little pricey. I have a Abbeon hygrometer that I used to send back to Abbeon every so often for calibration, they offer certified calibration services for their products.

Now I simply do a wet bulb test every 3 months, compare the results in the desired range that I maintain my shop to the Abbeon and calibrate the Abbeon as required. So far my Abbeon has not been more than 2% in a 3 month period which is pretty good.

Once you have a way of actually knowing what the RH really is you can use the digital and note on them how far that they are off in the range that you care about. For example I know that my Caliber III's are off 9% based on several tests that I did. So I use the Caliber III's anyway but just add 9%. Same holds true for the Stew-Mac white and blue hygrometer that I tested at being 11% off in our target range.

My Abbeon is my "at-a-glance" go-to hygrometer though and again every so often I check it with a wet bulb test.

I hope that this helps.

Thanks for the replies everyone. I think I will make one of the wet/dry bulb meters and buy a decent gauge for "at a glance" monitoring. I looked in the archives and the funny thing is it seems like 50% swear by the Caliber III and 50% claim its not accurate.

Hesh, which Abbeon hygrometer do you have? I looked on the website and they have multiple units.
https://www.Abbeon.com/store/categoryit ... ?catid=508

Edward my friend I have this one:



I can't comment on the other models for lack of any direct experience with them.

Mine came from Elderly Instruments and was about $150 IIRC: http://elderly.com/accessories/items/HYGROT.htm

My guess is, but it's a guess, that the actual mechanism on some of the other models may be the same. I know folks who have picked these up on eBay too for less cash.

I would recommend though calibrating it right out of the box. I compared mine when I bought it to a couple digitals, noted the differences, sent my Abbeon even though it was brand new for calibration and when it returned it had in fact been changed from how it was new-in-box.

This is yet another reason why this stuff is difficult to get a handle on with absolute certainty that what these things say is accurate. Once your hygrometer reads what your wet bulb test(s) read though you are good to go.

Thanks Hesh, I think I will get one of these... I am just tired of screwing around with this.
Nice bit cheaper on Elderly too.