Soooooo, after following the ever popular stove building trend for 4 years now I finally gave in and started tinkering. I think I have read every thread started on WB with "stove" in it...
I say finally since I do a lot of DIY stuff (yes I sent my dad nylon for christmas...lol) and knew that I would become obsessed once I started, so for the sake of my marriage I had avoided the alcohol stove like a plague.
But alas, I finally gave in (my bro gave me one for my b-day so it's his fault really :D) and have made about 10 in the last 2 days. Supercats, penny and pepsi can stoves are what I'm limited too since I am currently on a travel assignment and only have limited tools (cutting and punching stuff only) and cannot construct the fancy-shmancy ones, yet.

My goal was to ditch the Jetboil fuel cannister and replace it with a stove/potstand combo. The flux rings at the base are very efficient and seem to handle the central open flame such as a Starlyte the best. Larger circumference heat rings are not as efficient since most of the heat is lost up the sides (melting the rubber top IMO) The cozy goes on after the flame is out...
Since I want a stove to work with both regular pots and my jetboil cup, the supercat or any other "sit-directly-on-the-stove" types naturally wont work .

I have narrowed my preferences down to the penny:

(http://www.csun.edu/~mjurey/penny.html)

and the pepsi:

http://www.pcthiker.com/pages/gear/pepsiGstoveinstruct.shtml

(FYI - I have been using standard can sizes and I do not cut slits or crimp the burner walls - patience IS needed I have found that the best fit comes with minimal tampering of both ends. The stretch technique is all you really need. I have access to hyperdermic needles (RN) and the 14 gauge needles are 2.1mm or just a hair wider than the recommended 1/16th". I will check the 16 gauge to see if they are a closer match.) The work wonders to aluminum!!:D

A good chart: http://mdmetric.com/tech/cvtcht.htm

My initial penny stoves were identical to the instructions, but I have since tinkered a bit with them by placing 5 jets on the inside of the ring to direct the flames centrally, 6-8 were creating too high of a flame.
For the testing I pour a measured 15ml into the burner without the penny, place the penny and add 5 cc onto top. With 32*F equipement and alcohol (kept outside on porch) I have been required to drop 1 cc around base on first light to warm the stove up a bit. With the pepsi stove I just place the entire 20 ml into the central chamber and light.
It can take up to a full minute for the stoves to convert. Using the jetboil cup, a crude windscreen and an even cruder 3.5 inch potstand I have boiled 2 cups of cold water in about 6 minutes on the 20 cc of fuel.
Using only 15ml at these temps I was not able to boil 2 cups with either stove, 200* is close, but not rolling...

I apologize in advance to the likes of zelph, skidsteer, and Sgt Rock who have dealt kindly with us newbies....:rolleyes:

Questions -

1. In the penny stove, is it normal to have the fuel to actually boil? The little sucker seems to be burning almost violently... (too hot?)

I have heard that some can get their stoves to run silently which would appear to be more efficient. My stoves tend to convert, boil, then burn very intensely (6 inch jets) for 5-6mins then go silent and small (2 inch jets) for another minute or two.

2. How does the size of the hole effect the burn rate and size of jet?
If I am trying to maximize burn time without sacrificing temp what is the best combination between size and quantity that you have used?
My testing has been either a) short lived 5-6min flame thrower with smaller jets or b) 12minute mellow burner with large jets that again, can't boil 2 cups on 20ml.

I'm trying to get a longer burn time with less flame-thrower qualities.. Would a slightly larger fuel chamber decrease the potential pressure, hole size and quantity remaining constant? Or would it just take longer to convert?

3. For a pot stand I used a pretty sturdy aluminum can (corn). It fits the bottom of the jetboil cup perfectly and the stove sits in it. Crude triangles were cut removing about 65% of the can wall (fast burn with base or triangle at top, slow burn with apex at top - hasn't worked yet... :()
BUT WHAT IS THAT AWEFUL SMELL????
I will plan on never using it again...

4. In your experience, do the pepsi-types ever lose the central flame? It seems a waste of either holes, or gas to have the central flame burning while the jets are going at the same time.

5. What would be the best type of simmer ring for a penny stove? I ask since I made one for mine and noticed no difference in burn time, jet height or final temp. (based on the heine stove concept)

Alright, wife is calling, I have to run. Thank you all for your help and advice (past and future)
I do plan on posting some pics and maybe a burn video soon but have never done either on this site.

I will look forward to any advice you may have or any suggestions with what type of stove would work best for my jetboil concept.
Thanks again

Dan

I go back and forth on what my favorite stoves are. I like the supercat, because I can make one in one minute using a paper punch. However, I made a couple penny stoves today and I really only need a push pin and a pair of sharp scissors.

1. Yes, the fuel will boil. Alcohol boils at a lower temperature than water.

2. All things being equal (and it's not usually) one ounce of fuel has a fixed content of BTUs. Burning slower releases energy slower, so doesn't boil as fast. What you're looking for with a camp stove -- where you normally want to boil water -- is the most efficient transfer of energy from fuel to water. Other people have their standards, but I look for boiling two cups of water in six minutes with one ounce (30ml) of HEET. Both my supercat and penny stove do that.

For me, on my penny stove, 16 holes made with a push pin work ok. I have some concern about not having enough holes, because I don't know if pressure will build up in the can to pop it apart.

3. Burn off the can coating outside.

4. My pot is part of the stove system. Without the pot, the central reservoir will burn for a while and then go out. With the bottom of my pot reflecting heat down, the central flame will heat the can to flash point and then the jets will take over. All the available oxigen is then around the outer rim, so I only see flames from the jets.

5. I don't simmer with my alcohol stove. I'll do some variation of straw box cooking. I might try transfering the pot to my tea candle stove after it's reached boiling for extra simmer time.

Extra credit: put wicking material in your stove, so accidentally splashed fuel won't spray you with flames. I can say from experience that that sucks.

thanks whips, i generally use my stove to boil water (FBC) but once in a while some eggs or pancakes are nice in the am.
as far as the stench goes, i've been using the can for about 40 stove burns and the smell is pretty consistent. time to change pot stands.

thanks for the tip with wicking material - i've read several suggestions and i will try a pinch of the pink stuff tonight when i make another couple of stoves.
the pink stuff WILL work right? ---- i guess there is only one way to find out for sure.

thanks whips, i generally use my stove to boil water (FBC) but once in a while some eggs or pancakes are nice in the am.
as far as the stench goes, i've been using the can for about 40 stove burns and the smell is pretty consistent. time to change pot stands.

Boiled eggs just need the water brought to a boil. I fry eggs on my esbit with three tea candles. Haven't tried pancakes, yet. Nice thing about candle cooking is that you can even do it indoors.

Sometimes you have make a good size fire and give cans a thorough roasting to get off the paint and polymer inner coating.

Oh, and I've just noticed that my new extra short penny stove works nicely in my esbit stove; pot holder and wind shield just got chucked out of my kit.

alright, it's dark, cold and i finally snapped some pics of the 3 best operating stoves iv'e made thus far.
please feel free to criticize and bash them, they are in the first 15 stoves i've made in the last 2 days.

http://picasaweb.google.com/dneilson/Stoves/photo?authkey=Y48tsab6okQ#5144704616350107282

On the left is the jetboil stove with the jets on the inside of the ring. I added 4 more very small jets to decrease some of the pressure coming out of the larger jets and it seemed to work out. the top one is a regular heineken can stove and the right is the classic pepsi stove. you can also see my ghetto potstand and oven liner windscreen.

1/2oz exactly in each stove for time testing. all stoves were brought to room temp, the alcohol was around cold (it's 29* with freezing rain and 5knot winds)
http://picasaweb.google.com/dneilson/Stoves/photo?authkey=Y48tsab6okQ#5144704650709845810
the normal penny stove on right was first to go out at 4:40, the pepsi stove on left was 2nd @ 4:45 and the center stove remained lit for another 2 minutes and 20 secs getting over 7 mins on 1/2oz! not bad for day two! i will make another with insulation and see if that adds any time.

i have not compared these using a pot with water yet since i have no consistent set up with potstand etc. the nasty pot stand that i have been using somewhat alters the flame of each stove differently... i have boiled and maintained a rolling boil with the altered pennystove (5:30 boil time with about 1 minute of continuous boil thereafter using 1oz fuel)

this is a pic of my stove with just the windscreen:
http://picasaweb.google.com/dneilson/Stoves/photo?authkey=Y48tsab6okQ#5144704633529976530

this is the pic with potstand, windscreen and jet boil cup all together.
http://picasaweb.google.com/dneilson/Stoves/photo?authkey=Y48tsab6okQ#5144704624940041906

it is a poor pic, my apologies. the small lines at the top are the flux ring "gills" of the jetboil cup

anyways, there are more pics on my site if anyone is interested, i am new at this so just bear with the excited newbie :)

thanks

darn sorry to link you to pictures, i tried following the "post pictures" instructions... somehow it didn't work

Well its lots of fun when you first start out. now i been making all kinds of alochol stoves good and bad. On the jet boil i got two alcohol stoves to work with just the cup with the ring one. not as fast but it workes on 1/2 oz. fuel must get the holes just right so as to fan out and get the ring but not to hit bottom to much of pot get pictures if when this snow storm is over if you like

for posting pictures from picassa - go to the "link to this photo", change the pull down to the size you want, then copy the line titled "html to embed in website".

come back to whiteblaze, then hit the image button. you may need to switch to 'advanced' so you can edit the html. paste what you've copied from picassa into the image dialog box... hit ok. now go back and clean up some stuff.

for this image:
http://lh4.google.com/mike.beganyi/RzDRHyfwIOI/AAAAAAAADcI/VHa4DJCoY1w/s800/IMG_4272.JPG

delete everything but this:
http://lh4.google.com/mike.beganyi/RzDRHyfwIOI/AAAAAAAADcI/VHa4DJCoY1w/s800/IMG_4272.JPG

it should follow the "src" tag from picassa and end in .jpg to work.
when it is in the image tag it will place an image, rather than the link you see above...

I'm trying to get a longer burn time with less flame-thrower qualities.. Would a slightly larger fuel chamber decrease the potential pressure, hole size and quantity remaining constant? Or would it just take longer to convert?



Try cutting off the outer wall/fuel resevoir that sticks up above the jets. The flames look like are hitting that part of the burner causing an extreme amount of heat to be transfered to the fuel.

You may also be getting alot of radiant heat reflecting off your potstand. Make a potstand out of 1/2" hardware cloth.

This photo shows the flames touching the side of the burner:

Also check out the hole configuration on the Penny stove in this thread at BPL (http://www.backpackinglight.com/cgi-bin/backpackinglight/xdpy/forum_thread/10827/index.html)



http://img.photobucket.com/albums/v228/obijiwa/sub%20one/pennystove.jpg

i've played with various hole configurations on the pennys. tough to get them working well with interior jets. seemed they burned more fuel to do the same work as with the outer ring jets, and took longer to prime.

i've used 1/16" drill bits for the jets. did the 6, then 8, then 5, 12, etc. moved them in, out, etc. added wicks, added cloth to the interior.

as the jets warm that outer ring they help keep the stove burning (feedback loop). its a balance to get them to warm the stove, but not too much. putting it into a tight windscreen / heat reflector will do the same thing. was getting consistent 3/4 oz fuel boils for 2 cups water. could do 4 cups water on 1.5 - 1.75 oz fuel.

if you are worried about fuel consumption a penny might not be the way to go - as i've had trouble getting it to hit the marks published on the maker's site. its a great stove - but for small pots i found other stoves take a little longer to get going and use less fuel. adding a priming wick might make it more efficient. not sure, never tried.

for 5" and larger diameter pots i think i would use it... and i had good results with the top of the heiny can simmer ring. burned for a long time with that on...


have you tried a starlyte?
gram weenie?
cat stove?
whitebox?
ion?

thanks zelph, great suggestions and i will be trying out the hole config. on my next stove. i didn't expect the extended fuel cup height to make a difference since it should act somewhat like a simmer ring limiting the oxygen to the flame, or so i thought. i'll try it and let you know how it affects the burn time.

Bmike, great reply. i haven't tried any of the original build stoves that you mentioned but did try to make some of my own based upon their design. like i mentioned, while i tinker with the catstove types which require a pot to sit directly on the stove, i have concentrated most of my time to the stoves that could accomodate my jetboil cup. the other styles worked great but each stove i made was in dire need of tweaking.

i have noticed a greater difficulty in lighting the penny now that the holes are centered, sometime requiring 2 separate priming "squirts" of extra gas but that may have just been the significant drop in temps too, from around 35 to 20 degrees - i need to bring my fuel to room temp first to get an accurate test...
in the end though, they all burn well, feed the pyro-diyer in me and are generally lighter and smaller than my jetboil config., so let the fun continue.