Reusing hand warmers

There have been many times when I've thrown hand warmers away after using them for short periods of time, much less than the package rates them for at least. So, I did a little experiment recently with reusing hand warmers. Not scientific, but take it for what it's worth.

After using hand and toe warmers for about an hour, I sealed them in a plastic baggy. Then, I waited for over an hour. They were cool to the touch. I opened the baggy and left them out for another hour. They continued to produce heat, in an open environment. I sealed them up again and waited over a week. Again, they functioned for about an hour before giving out.

I do NOT recommend you RELY on used hand warmers. But you might be able to put the used ones back in your pack, and expect to get some decent use out of them before needing a fresh set.

It makes you wonder why they are not sold in resealable containers!

They react with air (oxygen I believe) to produce heat, so I don't know why sealing them back up shouldn't preserve them.

Reusable hand warmers

You might want to try these . I have not used this exact brand but was first introduced to them in a high school science lab where they were used for an experiment in an intro chem course.

Pat T

Pat T said:

You might want to try these . I have not used this exact brand but was first introduced to them in a high school science lab where they were used for an experiment in an intro chem course.

Click to expand...

They contain super saturated sodium acetate in water--they produce heat as the sodium acetate crystalizes out. (Recharge by placing in boiling water.)

IIRC they don't last as long as one-time use hand warmers and are heavier.

REI also has a version: http://www.rei.com/product/608751

Doug

Tom Rankin said:

After using hand and toe warmers for about an hour, I sealed them in a plastic baggy. Then, I waited for over an hour. They were cool to the touch. I opened the baggy and left them out for another hour. They continued to produce heat, in an open environment. I sealed them up again and waited over a week. Again, they functioned for about an hour before giving out.

Click to expand...

I wouldn't be surprised if the resealed ones have a shorter shelf life than the unopened ones.

Certainly worth a try as long as one carries unopened spares.

Doug

Don't the latter work by exothermic iron oxidation? So removing the oxygen source stalls/suspends/slows the reaction.

Tim

bikehikeskifish said:

Don't the latter work by exothermic iron oxidation? So removing the oxygen source stalls/suspends/slows the reaction.

Tim

Click to expand...

Yes, it's an oxygen deprivation thing. I knew it would work to some extent, I just wanted to find out if it was worthwhile. It seems it is!

Pat T said:

You might want to try these . I have not used this exact brand but was first introduced to them in a high school science lab where they were used for an experiment in an intro chem course.

Pat T

Click to expand...

I used to use those a long time ago. I don't know if they have gotten better, but they would not even last an hour for me. And they are heavier for sure. But, they are reusable, on the plus side.

Not to hijack the thread, but does anyone know of any warmers that work well in the oxygen deprived interior of a boot? I have tried a few that say they work, but they just don't. My feet get so freaking cold while belaying...

-percious

Tom Rankin said:

I used to use those a long time ago. I don't know if they have gotten better, but they would not even last an hour for me. And they are heavier for sure. But, they are reusable, on the plus side.

Click to expand...

This is from their website:

"HotSnapZ™ will typically stay warm for upto 2 hours down to 20 minutes, and then gradually cools down. Heat duration depends on: Size, How it is used, & How well the product is insulated during use."

The Grabber hand warmers claim over 7 hours. I've never used them for that length of time, but I know from experience they last much longer than two hours. However, not reusable after they die out.

percious said:

Not to hijack the thread, but does anyone know of any warmers that work well in the oxygen deprived interior of a boot? I have tried a few that say they work, but they just don't. My feet get so freaking cold while belaying...

-percious

Click to expand...

Hi percious,

I don't know which ones you've used, but I have used these and they worked just fine for a couple of hours. They claim 5+ hrs., but I didn't use them that long.

rhihn said:

Hi percious,

I don't know which ones you've used, but I have used these and they worked just fine for a couple of hours. They claim 5+ hrs., but I didn't use them that long.

Click to expand...

They will indeed last as long as they claim. The package I have here says 6+ Hours. This is not always long enough for a long cold day, so I have the dilemma of putting them in when I start (in a warm car), vs putting them on when I really need them, when my hands are subject to extreme temperatures. Sigh...

In any case, they have a sticky side, which works quite well, and they are thin enough that I almost never notice that they are in there.

Anyone using these handwarmers?.... http://www.restorationhardware.com/...oduct.jsp?productId=prod230102&navAction=jump

They will keep your boots nice n warm all night or put one in the bottom of your pack with your water or cameras to keep em warm.

paul ron said:

Anyone using these handwarmers?.... http://www.restorationhardware.com/...oduct.jsp?productId=prod230102&navAction=jump

They will keep your boots nice n warm all night or put one in the bottom of your pack with your water or cameras to keep em warm.

Click to expand...

Might not be good for keeping a camera warm--it looks like it gives off water vapor. Wouldn't want any of it to condense on the camera.

Doug

Store the camera in a zip locbag with a couple silica packets.

percious said:

Not to hijack the thread, but does anyone know of any warmers that work well in the oxygen deprived interior of a boot? I have tried a few that say they work, but they just don't. My feet get so freaking cold while belaying...

-percious

Click to expand...

Percious, I have boot insoles made by Heat Factory. They have a slot under the ball of the foot that takes a small chemical warmer about the size of a credit card. They last for hours and get almost too hot at first. I've used them in ski boots a couple of times. You can also use the insoles for hiking in warm weather; the warmer gets replaced by piece of foam. These warmers are also air activated and according to the website, can be used, then bagged and used again until the chemical reaction stops. They make a variety of packs, insoles, gloves, mitts, etc. I have a pair of their mitts also.
www.heatfactory.com

paul ron said:

Anyone using these handwarmers?.... http://www.restorationhardware.com/...oduct.jsp?productId=prod230102&navAction=jump

They will keep your boots nice n warm all night or put one in the bottom of your pack with your water or cameras to keep em warm.

Click to expand...

Paul,
I have had a large Jon-e-Warmers for many years - They run on Zippo type lighter fluid. but I have hear folks use Kerosene with them. They aren't as easy to use as the "rip'em open" disposables, but they certainly have a place in my pack in the winter for daytripping.
I think they are usually more closely associated with hunters, because they are a bit heavier, but there was a time when that was THE hand-warmer. I don't think in 25 years or so of hiking, that I have use it more than a dozen times, but I try to include it in my pack as a backup.

cold tootsie?

Hotronic makes battery powered foot warmers. I've use them in my ski boots and thought they were great. They make 2 versions, one for custom footbeds, and another that will slip into any footwear. I don't think the insoles are too thick so they won't effect the fit too bad.

They're not cheap but they do work. The batteries are much better than in the past. The do work all day.

Jim

rhihn said:

Hi percious,

I don't know which ones you've used, but I have used these and they worked just fine for a couple of hours. They claim 5+ hrs., but I didn't use them that long.

Click to expand...

I have used these toe warmers for years while skiing. The thing that I must do though is to use two for each foot. I put one under and one on top of the toe area of each foot. This makes all the difference for me. One underneath the toes doesn't do it for me. Doing this is the difference between skiing and not. Simply can't do it without these things.

For what it's worth and I have no real DougPaul like scientific data to support it but I have found that the placement of hand warmers and foot warmers to be critical when keeping my extremities warm. With hands I have had much better luck placing a chemical warmer on the inside of my wrist to keep my fingers warm rather than at the extremity area itself. The theory is that the blood is warmed on the way to the fingers rather than trying to heat a larger surface area once the blood has been dispersed to each and every digit. In other words your wrist is the conduit for the blood dispersion to your hand. Kind of like heating the water at the boiler room and then sending it off to each individual room after it is heated. Especiall handy too because you loose the clumsiness that the chemical pack can have in your glove when holding on to an Ice axe or ski pole.
I have used Hotronics in my ski boots for quite awhile and really like them on cold powder days. Last year I replaced my boots midseason along with the upgraded Hotronic unit. The couple first times I used them I found that the Hotronics were not keeping my toes as warm as my old ones. I removed the insole and found that the Ski shop had installed the heating pad directly at the end of the boot..at the tippy toes. I reinstalled the heating pad behind the toes just forward of the ball of my foot. WALLA! my toes were now warm again. Same theory as above described with the hands the blood now seems as though it is getting warmed before it reaches the end of the extremity therfore not giving the end of the toe a chance to get cold. Also again better and more efficient dispersion. If using a chemical toe warmer I would too recomend placing a bit rear of the end of your toe rather than right on the end .