Friday, January 2, 2015

Thinking about stoves

It seems that kinda the default question people ask themselves about camping stoves is "how fast does it boil?"  Speed is what it comes down to right?  But if we chose bikes based on how fast they could go on a given surface (say pavement) we'd all be riding road bikes with 19 mm tires (the previous Arrowhead record on a bike, that stood for years, was set on a regular old 26" mountain bike - it was set in, I believe '07 and stood until '13.  As far as I know the single speed record was set on a regular 29er - hard packed snow favors skinnier tires and less rotating weight - even on snow sometimes a fatbike isn't the fastest).  I got to thinking about that - stove speed specifically as it applies to Arrowhead (be it on a bike or pulling a pulk while skiing or whatever).

There's alot of talk about how fast a white gas stove is.  It really puts out the heat - boils water (or melts snow) fast.  If you run a drag race of a white gas/canister (or any non alcohol stove that I'm aware of) stove vs an alcohol stove the white gas/canister stove will win by a long shot every time.

Problem is that's not, as I see it, the relevant question.  The question isn't "how fast does a stove perform once set up?" it's "how much time does it take me to go from a stove in the stuff sack, melt enough snow to get me down the trail, and then pack it all away?"

For a test in temps like we might see in Arrowhead I put on mittens (even though I may not have needed them in the conditions the test was being run: 10 degrees and roughly 4 mph winds).  I tested the alcohol stove first (Zelph Stoves Companion Burner).  A brief summary of the setup process: stove, potstand, and 4 ozs of alcohol fit inside of the pot.  Lower heat reflector and wind screen fit inside the same stuff sack but not in the pot - it's all contained in one sack.  It fits in the lower compartment of my frame bag.  I pulled out the windscreen, unfolded it, got out the lower reflector, set it on the snow, removed the stove and set it in the middle of the lower reflector, poured two ozs of alcohol in and lit it with a match (UCO Stormproof) (the only part I took my mittens of for),  then put on the potstand, placed the windscreen around it.  Then I filled the pot up with snow and set it on the potstand.  Probably about 2 minutes from everything in the sack to melting snow.

I melted a full pot of snow (24 ozs) and then with a sharp puff of air blew the stove out (it was still going strong but the ability to blow out an alcohol stoves relies on it being a wick stove), poured the water into a Nalgene, and packed everything up.  When I had it all packed away I stopped my watch at 24:26.

Next for the MSR Whisperlite.  The stove will not nest in my pot so I have a sack for my (mostly empty but for a match safe) pot, and a separate sack for the stove, and the fuel bottle (which is an integral part of the Whisperlite) stored separately too.  Having them all ready to go I started the timer and started setting it all up.  The lower reflector needed to be unfolded and threaded onto the stove unit before spreading the support legs of the stove, the windscreen needed to be unfolded then the pump/fuel bottle needed to be attached and pumped, the fuel released into the priming cup, light the priming cup (again I took my mittens off to light the match), wait for the stove to prime (I used this time to fill the pot with snow and start melting a bit of snow for seed so I didn't scorch the water).  It was almost 10 minutes in before I was starting to melt snow.

I melted a pot of snow (I had eyeballed what was a "full pot" in both of the tests and so ended up melting 24 ozs of water with the alcohol stove and 28 ozs with the Whisperlite), shut off the stove, dumped the water in a Nalgene and folded up the windscreen, had to wait a minute for the stove to cool off enough to pack (the alcohol stove's burner is mostly made of a aluminum can [but is quite a bit thicker than just a pop can] cools down in a few seconds - about as long as it takes to fold up the windscreen), packed it up, and stopped the clock at 23:13.

The Whisperlite was, as expected, much faster when it was actually melting snow.  But when considering the performance from packed up stove to melted snow to packed up and ready to go the two were remarkably similar.

A few things that draw me to alcohol stoves in general:

1) The stove in this test is made by a non-huge-corporation and costs $15.  You can make your own alcohol stove - I have a whole bunch.
2) It's lighter than the Whisperlite.  The Whisperlite weighs about a pound.  This alcohol stove weighs 3.5 ozs (this includes the potstand).  For summer use I've got perfectly serviceable stoves that weighs .3 ozs and is its own pot stand (but it doesn't pressurize reliably in cold weather so it'll stay at home).
3) It packs better.  As mentioned before, the burner, potstand, and a 4oz bottle of alcohol all fit inside of the  pot.  The other things (windscreen and ground reflector) fit inside of the same sack.  It all fits in my frame bag.  Everything's in a single place - the Whisperlite requires the pot, stove, and fuel bottle to all be a separate sacks.  When things are cold and dark and you're delirious from fatigue the advantage of having everything in one simple, easy to find spot is hard to overstate.  Also the time my stopwatch reported didn't include wrangling up the stoves - when I started the timer they were right beside me.  If I included the time spent getting all the stove sacks together (3 separate for the Whisperlite and a single one for the alcohol) and putting them back in my bike bag the time difference would be even closer - or maybe even favored the alcohol stove.  The way the alcohol stove packs down will also allow me to have an 8 oz bottle of fuel (to meet race requirments) packed separate that I will leave untouched (except life threatening emergency) and just use the 4 ozs I keep in the pot.  Can't do this with the Whisperlite: the small fuel bottle I have holds 11 ozs but the fuel bottle has to be used when the stove is used.  If I use any fuel I have to make sure that I only use 3 ozs to meet race requirments of finishing with 8 ozs.  I don't plan on taking a measuring device with me.  On the other hand I've never heard of anyone ever being checked. 
4) No moving parts, seals, or almost anything else to fail.  The Whisperlite has umpteen moving parts, seals, and teeny-tiny little parts that would be a nightmare/impossible to fix in the field at 30 below.  You'd pretty much have to step on the alcohol stove to render it unusable (something that would also do in the Whisperlite).
5) It's silent.  The only sound you can hear with most alcohol stoves is the water as it begins to boil.  The Whisperlite, despite its name, roars (and is also not light relative to an alcohol stove - as you saw in #2).

This stove is uses carbon felt as a wick (to read about wick stoves go here) which serves a several of functions a couple of which are especially attractive for Arrowhead: The wick vaporizes fuel more readily - which is important in cold weather.  The wick absorbs the alcohol so once you pour the alcohol in it will not pour back out meaning if you accidentally knock the burning stove over (with a clumsy, hypothermic, mittened hand) you won't spill flaming alcohol all over. 

I don't mean to poo-poo the Whisperlite too much.  It's a good stove and a workhorse.  Once its set up and running it is far and away faster.  And, of course, if one was melting more snow than I did the time difference would be greater.  I've carried the Whisperlite on all of my past Arrowheads.  I have yet to test out the alcohol stove at really low temps (-5 is the lowest) and the Whisperlite may very well go with me again this year as alcohol stove performance drops off as things get cold.  On the other hand mushers in extreme cold situations rely on wick alcohol stoves to heat up food and melt snow for their dogs.  It's had decades of field testing and is tried and true.

I also realize that the times here may not be very representative of results you would have if you were using a canister stove (something faster to set up) or were just plain faster than I at setting a Whisperlite up.  It's what I had so it's what I tested.

If you like your non-alcohol stove by all means use it.  If it works well and suits you, far be it from me to be try and convince you otherwise.  I think the most important thing is to get out there and use it.  An alcohol stove suits me.

7.3 ozs for the stove, pot stand, windscreen, ground reflector, and a couple of empty 4 oz fuel bottles.   I haven't yet bought an 8 oz bottle but I will and will fill that with alcohol and pack it separately for the race - one less thing to unpack and repack if I need the stove during the race.
It's a snap to set up.  1:08.  The mittens I was wearing are on the left.

The alcohol stove packed up inside the pot.  One of the bottles will fit inside, too.  This all fits in my frame bag - I just have to find a single bag if I need the stove.
15.5 ozs without the stuff sack

1 lb .1 oz

2:24 set up time.  It was slower to set up outside (as was the alcohol stove) because I was wearing thicker mittens - more like I would probably be using in Arrowhead

1 lb 10 ozs with empty fuel bottle

1.7 more ozs if you want to take a repair kit along

The stove will not fit in my pot so I need to pack it in three separate places - more hassle if I need to use it during the race.
Since were talking stoves:

Just for fun (I don't plan to take it on Arrowhead) I'll show you the wood burning camp stove that I got for Christmas.  It is called the Solo Stove, fit's inside of the pot for easy carrying, and weighs 9 ozs.  It just feels right to have some kind of wood fire at camp. 

It's double wall and reinjects preheated air mixed with some of the unburned gases that would normally just go up in smoke.  You can see the jets coming in from the left.