To start off:
I have just bought a few new Jon-E handwarmers. These use a liquid fuel to power them. Heat is generated by an exothermic catalytic reaction, using platinum wires or wool as the catalyst.
These were bought from Scotts Bait and Tackle (
www.scottsbt.com). They came in a packaging different to what you normally see on other on-line stores. It is a clear plastic clamshell package, whereas the pictures on the other websites seem to be a blister pack with printed cardboard backing. I wonder if the version I got is the newer or older packaging and whether there has been any small changes to the design of the handwarmers.
Years ago, I bought a couple of other handwarmers, not from the Jon-E brand. The big difference was that it didn't have the wick on the side and seemed to use a bit of platinum wool rolled in a wire gauze, rather than the woven stuff that Jon-E uses.
I think that the Jon-E design has a major disadvantage in that the wick continues to vaporise fuel even after the flame has been blown out and the catalyst is running. It seems very wasteful as I'm sure most of the fuel vapour from the wick is missing the catalyst.
A quick test seemed to bear this out. I loaded both my old non-Jon-E handwarmer and my new Jon-E handwarmers with similar amounts of fuel. The Jon-E ones come with a filling jug and I loaded each handwarmer with 1 measure of the filling jug. (The instructions state that it a full fill is 2 measures).
Both seemed to get to the same temperature, but the Jon-E handwarmer burned out about a half hour before the off-brand handwarmer. I forgot to check the starting time. Also, the smell from the off-brand was clean with no odour, while the Jon-E version definitely smelled of unburnt fuel. Anyone else noticed this with their Jon-Es? Has anyone tried to plug up the wick to stop the smell? I know having the wick there makes lighting easier, but I wonder if it wouldn't be better without the wick. One can light them almost as easily with a proper Zippo.
I held an open flame close to the case and actually had the Jon-E version burst in to flames. Nothing happened with the off-brand version.
Pity I can't recall where I bought the off-brand version from, but it was quite a few years ago when there weren't many online stores selling these handwarmers. The only one I remember looking at was safetycentral, but they weren't shipping internationally at that time.
Anyway, a note about the fuel. I've never used Jon-E branded fuel as it has to be sent by ground, so I don't know if there is any noticeable difference in operation quality between the branded fuel and generic fuel.
I did note that Jon-E fuel is supposed to be Naptha, which is also the predominant component of Shellite, Zippo fuel and Coleman Fuel. I can't find an MSDS for Jon-E or Zippo fuel (though I found one for Rosonol). However, the MSDS for Shellite and Coleman both show that the fuels are composed of greater than 95% Naptha.
I have used Zippo fuel and Shellite with no noticeable ill effect. At some stage I may try Coleman fuel. Has anyone else got any other fuel recommendations?
BTW, has anyone tried the "1955 handwarmer" from restorationhardware.com? At $15 a pair, it has to be the cheapest one I've seen. Does it have a wick?
Also, I noticed that the finish on my off-brand handwarmers is very nice and smooth, like it was properly polished and buffed before being chromed. The Jon-E ones are much rougher, like it had been put through a drawing former that had been over-used, then not even given a cursory rub before being chromed. The 1955 ones look to have a beautifully buffed finish.