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So, I've been very happy with my hot hide glue setup over the past year. Things are working really well.

Not being smart enough to let things be good, I decided to see how accurate, or inaccurate, my various meat thermometers are. I have two of the dial types and one digital. Well, darn it, they vary from each other a significant amount.

Making sure the glue is hot enough is pretty easy; if it is liquid, it is hot enough. My concern is whether I might get it too hot by accident, because of my reliance on these dagnab cheap meat thermometers.

I found some used lab thermometers on eBay of a higher quality than what I have been using, but at a pretty low price from being used. One is a partial immersion lab thermometer, and the other is one of the digital jobs that has a probe and runs on batteries. Both have decent ratings in the lab world. Hopefully, I can use these to keep a closer eye on the upper temperature of my glue.

This got me to thinking that I don't recall anything on the OLF that talks about thermometers for glue, accuracy, that sort of thing. What do other hot hide glue users rely on for measuring the temperature of the glue?

To those of you who are now cursing me for bringing up another thing to obsess about that we shouldn't, I apologize. I really do.

If you want to check your thermometers for accuracy, test them in boiling water. If one of them reads 220*F, you will know that it is reading +8*F, and so on. Height above or below sea level will change the boiling point of 212*F

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

I use a digital meat thermometer, in the water bath, which is usually about 3-5* hotter than the glue.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

when I first moved to sea level from Colorado, I burnt the crap out of my mouth every morning on my coffee before I figured out what was going on. -2 degrees for every 1,000 feet.

Couple of pics tell the story for my home shop:

That is too funny - I moved to San Diego from Durango in the early '80s. Had the same problem - drinking coffee on autopilot in the morning

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Steve Smith
"Music is what feelings sound like"

That setup looks pretty familliar


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Yep, the Taylor digital thermometer is similar to one of the three thermometers I put into the same glue at the same time and got three different readings. I'm just saying that, while they work (in the sense that they respond to temperature changes) and are convenient, I'm not sure they are accurate or properly calibrated. They are probably like inexpensive hygrometers in that sense.

I again apologize for adding something to the list of things to tinker with.

I again apologize for adding something to the list of things to tinker with.

Isn't that what we do here? I think it is a valid question, and might get other's to check if they are getting accurate temperature readings. Thanks for asking, Don!


Alex

_________________
"Indecision is the key to flexibility" .... Bumper sticker

I used a Thermapen in the water bath to figure out which setting got me to 140f but didn't worry about it much after that. I'm most concerned to keep it from getting too hot. When the glue is hot enough to turn the consistency of skim milk it's ready...(What did Tony Stradivari do? ;') )


My baby bottle warmer died a violent death. Now I use a Yeti knockoff cup and lid. ~half filled with boiling water and adjusted with a little cold water to 160 and float my frozen plastic squeeze bottle of glue on the hot water in it. It's ready in a few minutes and settles at 140. It does an amazing job of keeping the water bath temp stable.

Hesh,
I was quite certain you had lost your marbles. I stand corrected.

Stable boil. 212-13(2x6.5 altitude correction)=199.

This Taylor guy is a craftsman!

We use lab quality thermometers to check any other thermometer in our shop. We keep the lap quality thermometers around for wet build testing and an additional calibration check on our hygrometers.

My Taylor was right on when I checked it.

Then the odds are my Taylor was the one of my three that was right, and the two dial thermometers were wonky. That's not a huge surprise. I'll check against the better thermometers (recently delivered) this weekend.

Thanks, all!