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chris
10-10-2002, 10:04
I'll try to use Sgt. Rock's review format here.

Name: Chris
Age: 28
Height: 6'4"
Weight: 210 lbs
Experience: 4 years solo hiking, plus boyscouts. Extended trips in the Sierras, Rockies, lower Cascades, Smokys, Nepal. Exploratory mountaineering in northern British Columbia.

Similar products used: None.
Locations tested: In my kitchen, although similar models have made two 3 day trips with me into the Smokys.


Weight: .2 oz to .3 oz depending on model.
Price: Free
Manufacturer address: Your home.

Description: The lackwit stove is an alcohol stove for the mechanically challenged. That is why I built one. Since I am not that creative, I most likely saw this idea in use by another hiker or on a website. The lackwit stove is just the lower third of a beer can, with some insulation stuffed in it. That is all. So, if someone steps on yours and squishes it flat, you can easily make another one in a hurry. The purpose of the below test was to examine the effects of the insulation on the performance of the stove.

Fuel Used: HEET gasline antifreeze (methyl alcohol, I think).

Amount of water: 1 pint

Pot used: 1.5 L MSR blacklit pot with lid.

Stove stand: Homemade from a coffee can.

Warnings: I did this in my kitchen without a way to accurately gauge boiling. I used the same method as I do in the outdoors: When I see a significant amount of steam coming out, I call it a boil. Times were kept on a watch and weights measured on a scale. Specific numbers might vary for you, but hopefully the relative results will hold.

Process: I built 4 models, each with a varying amount of insulation (fiberglass, pink type). I ran 3 trials for each stove, corresponding to 1 (A), 1.5 (B), and 2 Tbs (C) of fuel. There are .5 oz per Tbs.
I recorded the amount of time to boil and the total length of burn.

Stove 1 (S1): No insulation.
Stove 2 (S2): A small, wispy bit of insulation.
The bottom of the stove is clearly visible
throughout.
Stove 3 (S3): The lower third of the stove has
insulation. Cannot see the bottom.
Stove 4 (S4): Stove is packed full of insulation.
This is the only stove where the amount of
insulation registers on my scale (.1oz).

The first three stoves weigh .2 oz.

The tests.

A,B,C refer to the fuel amounts above. Time is
measured in minutes, seconds.

Boil time.

Stove| A | B | C |
------------------------
S1 | - | 6,12|8,04 |
S2 | - |5,37 |5,50 |
S3 | - |7,08 |7,35 |
S4 | - | - |7,37 |


Length of Burn

Stove| A | B | C |
------------------------
S1 |4,50 |8,04 |10,37|
S2 |4,35 |7,27 |11,57|
S3 |6,03 |8,20 |10,33|
S4 |9,14 |8,24 |11,15|

Conclusions: It is clear that stuffing the stove fuel of insulation reduces BTU output significantly, increases total burn time on the low end of fuel use, and hence should not be used.
It appears that a very small amount of insulation provides the best stove characteristics, but that not using it does not significantly reduced stove performance, at least in real world uses. Which one will I carry? Probably stove 2. However, I have a couple of other lackwit stoves that are in the pipeline, including one with a built in icemachine.

DebW
10-10-2002, 14:13
Chris,

Can you give us the diameter and height of your stoves? Also, your definition of boiling may differ from others (significant steam vs. rolling boil), but since you state it clearly, that's OK. When I start with unfiltered/untreated water, I prefer a full rolling boil before I cook. I'd be interested to see how these stoves compare with the "Linguini" type where the insulation is around the inside edge of the can only (you needs some wire window screening to hold it in place). My tests showed this to be better than filling the whole can interior (or at least longer burn times). I agree that K.I.S.S. stoves are great - so easy to make, so easy to replace.

chris
10-14-2002, 16:56
The height of the stove is 1.5 inches (down to the refund info). They are made out of standard beer cans (Old Milwaulkee, in fact), but I do not have an exact diameter measurement. I'm currently testing the effect of diameter, so all will be reported when I finish testing.

My scientific procedure for testing is definitely less precise that Sgt. Rock's. But, I don't own anything that allows me to record temperature. When cooking on a trip, lots of steam escaping is my rubric for deciding on boilage.