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View Full Version : SGT Rock and Ebay?



jim_the_hiker
2004-09-14, 16:56
I was looking thru Ebay for a new stove and I came across a product that is compared to SGT Rocks stove

Here's the link
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=62117&item=5123336209&rd=1 :boxing:

Lanthar
2004-09-14, 18:57
You'll find discussion on the Vargo Titanium... here (http://hikinghq.net/forum/showthread.php?t=849&highlight=vargo)and here (http://hikinghq.net/forum/showthread.php?t=909&highlight=vargo)

SGT Rock
2004-09-19, 19:49
Very funny

Two Speed
2004-09-20, 20:52
Haven't tried one of these yet, but I do have a couple of observations, based on building and buying a few alcohol stoves.

The Vargo is a pressurizing stove, as opposed to an open cup style like the Brasslight or Trangia. So far, my experience is that pressurizing stoves are slightly more fuel efficient, but suffer from two serious drawbacks.

First, for a pressurizing stove to work, it must be heated sufficiently to get the alcohol to vaporize AND provide enough quantity of vapor to pressurize the stove. Until the pressurizing stove is hot enough, heat output from the burner end is very low and it's very wind sensitive; it blows out real easy. Wind screens help, but they have to be very good, or the stove may never develop enough heat to really light up. The cup of a open cup style seems to shelter the flame in the stove, so the wind can blow, but blowing the stove out is just more difficult. Not impossible, but definitely more difficult. With the pressurizing style, all that has to happen is for the flame to be separated from the body of the stove for slightly longer than a fraction of a second, and that thing is out. Can be relit usually, but you got to nurse the darn thing more, and I have had to reprime. If you have to repeatedly prime a stove to get it to heat, any efficiency advantage quickly gets wiped out.

Second, most pressurizing stoves seem to be more selective about the quality of fuel used. I've got a Simmons alcohol stove (open cup, non-pressurizing) that smokes like sin on 70% isopropyl alcohol, and soots something fierce too, but it will light reliably on that crap. All the open cup style stoves that I've built seem less sensitive to fuel quality. They won't all light on 70%, but readily light up on 90%. I usually use the denatured alcohol that hardware stores sell as paint thinner, but I would like the flexibility to use 90%, if not 70%, which doesn't seem to be an option with pressurizing stoves. Isopropyl alcohol doesn't seem to have the vapor pressure to reliably light a pressurzing stove if has any amount of water in it.

I've been playing with pressurizing style stoves based on a Red Bull sized can, and have taken prototypes on the trail for two and three day hikes in mild weather, using denatured alcohol. Based on my limited experience, I suspect that while the pressurizing style is a fascinating exercise from the engineering perspective, it's a dead end from the practical standpoint. You certainly can make a pressurizing stove that will work, but my take is that the pressurizing stove is going to take more futzing around and is more likely to give you fits trying to light it than the open cup styles, whether your stove is a commercially marketed stove or home made.

Rock, does this track with your experience?