Capillary Hoop Stove discussion

[BirdBrain]

Thanks BB. I have one more question. When making the indentations to form the ribs, does that dent extend all the way to the hoop or does it start below the widest part of the can - the rim just below the hoop. When making the dents it is easy to dent the side as it bends in only one dimension. But the rim bends in the opposite direction, across the rib, so extending the dent to this point requires a bit more force and when it dents it deform the hoop. Without this indentation I worry that fuel won't make around this rim but getting the rim to dent has been problematic. How is this done in your best balanced stoves?

I have watched TetKoba do this. His hands must really be strong. He does it in one motion. I have noticed that he is getting better at "squashing" the space between the ribs. I suspect he has changed his methods. The rib needs to be as uniform as possible all the way up with no obstructions. There are 2 problem areas. The hoop is one. The tabs is another. I solve the hoop problem by denting that area 1st. I use a triangle file held in a vise and push down with my thumbs on the sides of the dent I am tying to make. This is tedious work. Gauging the pressure is difficult. The moment it starts to give, you must react quickly and stop pushing because it will go too far. I make the top dent at the hoop first and then use that dent with the cuts in the tabs as a guide to form the crease for the rib. My aim is to end up with a rib that is uniform from tab to hoop. Check out TetKoba's latest ribs. A thing of beauty.

[Odd Man Out]

I try do something similar with denting the rim, except I do it by hand, I use the triangle scale, and I tend to do it last. But sometimes that dent collapses and you really deform the rim. I also tend to cut the tabs last. I will try doing these steps first next time. Is TetKoba still cutting the tabs with a hacksaw? I gave up on that and use a scissors, but I could see that sawing the tab could give a space between tabs that could help with consistency. I wonder if cutting a V would be a good idea. I practiced using a nail on a pliers to make dents yesterday and came up with something that looks more like that picture. By hand, the ribs are large arcs of constant radius that go from one depression to the next (scalloped is the adjective that comes to mind). I think I need to work on more sophisticated jig for this.

[BirdBrain]

He has changed his methods. He used to use a hacksaw. JSB uses scissors. It appears now that he is forming the ribs in entirety and then cutting the tabs with scissors. I use cuticle cutters. They are precise and sharp. Ever since I pondered why JSB makes a secondary hoop, I have tried to replicate what he does. JSB seems to have a better engineering background. He talks about rotary engine designs and such. It is hard to follow because of the language barrier. I search for activity between the 2 friends. It is on twitter and gets deleted quick at times. Anyways, I have concluded that the gaps between the tabs are not desirable. From TetKoba's latest builds, it appears he has concluded the same. His tabs now overlap. I believe the secondary hoop acts like a baffle to discourage changing movements. Picture placing a sheet of plywood in the surf near the beach. Of course you can't stop the surf. You can stop the pulse in the hoop. The pulse could be stopped by opening the aperture instead. This increases the power and runs the risk of bubble bomb. I choose to close the aperture until the pulse would begin and the regulate it with the baffle (secondary hoop). This (along with proper rib and jet construction) seems to achieve the balance I desire. If you look at how his stoves start, you will see a slight pulse as the jets form. Watch how the flames form in my video. They smoothly climb. His construction abilities far exceed mine. I have a couple tweaks his stoves could benefit from.


https://www.youtube.com/watch?v=BepwaJrYpcM


https://www.youtube.com/watch?v=uTr4kHkllzM

[aero-hiker]

One other thought and then I must bow out of this conversation. I intend to not blog as much as in the past. It consumes too much time. This conversation is pulling me back in again...

Sorry to distract you, and thanks for your time. I think I have gathered plenty of information to get me off the ground for an attempt at V2 of the stove. Thanks for all your help and input.

[aero-hiker]

I try do something similar with denting the rim, except I do it by hand, I use the triangle scale, and I tend to do it last. But sometimes that dent collapses and you really deform the rim. I also tend to cut the tabs last. I will try doing these steps first next time. Is TetKoba still cutting the tabs with a hacksaw? I gave up on that and use a scissors, but I could see that sawing the tab could give a space between tabs that could help with consistency. I wonder if cutting a V would be a good idea. I practiced using a nail on a pliers to make dents yesterday and came up with something that looks more like that picture. By hand, the ribs are large arcs of constant radius that go from one depression to the next (scalloped is the adjective that comes to mind). I think I need to work on more sophisticated jig for this.

OMO, I tried to notch the tabs with scissors for my first stove... and used a triangle scale to make the ribs by hand. I like your rubber tube, finishing nail, and pliers jig idea. I'll have to give that a try. It would be way too expensive, but getting a die manufactured is tempting... not gonna do it though--as much as I love solid works and pro-E.

I'm also going to try polishing the inside of the collet and the bottom of the tub, and the jet ring before bending, cutting and assembling. The inside of the jet ring on my CHS-u has gotten discolored where the polymer inner lining of the can has been exposed to high temperatures. My thinking is that with a more reflective surface I might be able to help limit the thermal feedback and the stove overheating + "bubble bomb"

[Just Bill]

believe it or not...
It is interesting to see literally some of the best in the world at something discuss it.

Also neat to see how backpacking in general brings so many backgrounds, disciplines, and even folks around the world together in unexpected ways.

Keep at it BB.

[Casey & Gina]

The pot I was considering buying was the Toaks light 700ml. One source I found says it's about an ounce lighter than the aluminum grease pot, and I sometimes worry about the dangers of consuming aluminum; IIRC it has been implicated in Alzheimer's and dementia, both of which run in my family. (To be fair, however, it is a 700 mL pot whereas the grease pot is ~1.3 L, so it's actually almost half the capacity for 2/3 the weight.) The other problem with Aluminum is the ability to put it on a camp fire. I am thinking about making a caldera cone rip-off out of titanium... I know Dutch sells some Ti sheet.

Toaks is fantastic. I have a 1600ml pot with bail, 145mm diameter pan, 1100ml pot, and a 450ml cup. I also have the wood stove, alcohol stove, and 2 styles of tent stakes from Toaks. Everything is a winner of a product. Everything but the stakes nests together nicely. Shoot if their wine flask were bigger I would get one to carry alcohol fuel in, lol.

Please note that if you want to avoid aluminum, there is a small amount in some Titanium cookware and utensils, which uses an alloy which often also includes palladium, vanadium, and/or tin. However TOAKS cutlery, cups, pots and wine flasks are made from Grade 1 or Grade 2 pure titanium.

[squeezebox]

believe it or not...
It is interesting to see literally some of the best in the world at something discuss it.

Also neat to see how backpacking in general brings so many backgrounds, disciplines, and even folks around the world together in unexpected ways.

Keep at it BB.

Yep!! you're right. In my experience pretty much the same with cycling, and running. Not so much with bowling.

[squeezebox]

believe it or not...
It is interesting to see literally some of the best in the world at something discuss it.

Also neat to see how backpacking in general brings so many backgrounds, disciplines, and even folks around the world together in unexpected ways.

Keep at it BB.

Yep!! you're right. In my experience pretty much the same with cycling, and running. Not so much with bowling.

[squeezebox]

Can you send me to a good utube on how to make one. I'm a carpenter so if it's not wood I pretty much don't know how to make it.
Yes I'm kinda surprised to listen to a bunch of PHD's playing with beer cans.
Maybe we can start a discussion if the bicycle spokes on your rear wheel should be tuned to high C on the right and A below middle C on the left, of course carbon vs steel might affect that.

[Odd Man Out]

believe it or not...
It is interesting to see literally some of the best in the world at something discuss it.

Also neat to see how backpacking in general brings so many backgrounds, disciplines, and even folks around the world together in unexpected ways.

Keep at it BB.

I was at the hardware store yesterday buying an 0.6 mm drill bit and a Pin Drill. These are hard to find, but we have this old fashioned local Hardware store in town that sells everything. You can even buy and individual 0.6 mm drill bit in a zip lock bag. It's so small, you swear you are buying an empty bag. Anyway, in these kinds of stores, they have so much stuff you have to ask someone to help you find it. But in these kinds of stores, they actually have employees who can help. So the guy showing me the Pin Drill and asked why I would want to drill such a small hole. I'm thinking to myself "do I really want to try and explain it". I just said "I have a strange hobby". He said "but I like strange hobbies", so I explained what we are trying to do. It occurred to me that this really is a strange past time. Even my family will roll their eyes when I go to the basement to play with my toys when I could be watching "Finding Bigfoot" or something. At this point, my system works fine and I could live with it. It's probably more effective than 99% of the alcohol stoves out there and being better than the other 1% isn't my priority. Learning more probably at this point won't reap significant practical benefits, unless you count learning and having fun learning as practical benefits.

[BirdBrain]

This might be another which came first (the chicken or the egg) thing. Is it that strange hobbies bring people together from all over the world or is it that people have to search the entire world to find other people that share their strange hobby?

[aero-hiker]

Can you send me to a good utube on how to make one. I'm a carpenter so if it's not wood I pretty much don't know how to make it.
Yes I'm kinda surprised to listen to a bunch of PHD's playing with beer cans.
Maybe we can start a discussion if the bicycle spokes on your rear wheel should be tuned to high C on the right and A below middle C on the left, of course carbon vs steel might affect that.

Squeezebox,
I followed TETKoba's videos... the only problem is for the CHS-u the instructions are kinda split across 2-3 videos. First start out with his FAQ video for tools, techniques etc.


Then watch/skim the CHS-u video for some of the dimensions and construction techniques:


Then some tips/other facts and dimensions:


Or browse his channel for eCHS... eCHS is probably easier to make and uses 1 can instead of 3...

[aero-hiker]

OMO what cans do you use for eCHS?

[BirdBrain]

Argh! I can't stop peeking. Nestle Milo makes the best collet. Top rim is as large a diameter as you can get in US. Also makes for largest hoop volume. V8 can makes good body. Red Bull is too flimsy.

Okay. Off to work.

[Odd Man Out]

OMO what cans do you use for eCHS?

I've used V8 Juice cans, Ocean Spray Juice Cans, and some energy drink cans I pulled out of the recycling dumpster (don't know what brand). May have used a Red Bull can once. From what I can tell they are all pretty much the same. I know they have the same diameter. If there is a difference among them it is very subtle. In the eCHS video (14 sec), he shows that the key is for the diameter of the top rim of the can to be the same as the sides of the can. Hold two cans side by side and the rims should touch. With all of these, the rims don't quite touch, but they come very close (within a mm or two). In the video BB posted, he shows three different bottom profiles. I'm not sure which these are but I don't see a big difference. When can shopping, it seems to me that there are 4 can diameters. These are the smallest. Then there are small pop cans (like the 7 oz Pepsi). There are the standard 12 oz pop cans (which can have a larger volume if taller). Then there are some giant sized cans - I see these a lot with canned Iced Tea. I think all of the others have a top rim diameter that is much smaller than the side diameter.

[aero-hiker]

where in the world does one find Nestle Milo?! I'll keep my eyes peeled... might have to settle for V8, RedBull or similar...

[Just Bill]

http://www.amazon.com/Nestle-Milo-Ch...ords=milo+cans

Try a mexican grocery store or neighborhood store first.
Nido (milk powder) isn't by the other milks in my grocery store but in the amigo aisle.

[Casey & Gina]

http://www.amazon.com/Nestle-Milo-Ch...ords=milo+cans

Try a mexican grocery store or neighborhood store first.
Nido (milk powder) isn't by the other milks in my grocery store but in the amigo aisle.

It's in the Asian markets here. @aero-hiker - look up Lotte, H-Mart, Great Wall, etc.

[4eyedbuzzard]

believe it or not...
It is interesting to see literally some of the best in the world at something discuss it.

Also neat to see how backpacking in general brings so many backgrounds, disciplines, and even folks around the world together in unexpected ways.

Keep at it BB.

Yep!! you're right. In my experience pretty much the same with cycling, and running. Not so much with bowling.

This might be another which came first (the chicken or the egg) thing. Is it that strange hobbies bring people together from all over the world or is it that people have to search the entire world to find other people that share their strange hobby?

Little surprise that such interests should arise in a place people regularly gather regarding the activity of spending thousands of dollars to live like a homeless person while slowly walking absurd distances to ultimately go nowhere they need to be.