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Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Titanium Windscreen Design on 01/18/2013 20:31:04 MST Print View

Dandy Dan Durston has had an influence on me. His work with ti Windscreens and the StarLyte burners has been extensive to say the least. Thanks Dan for the inspiration and driving force.

My windscreen desingn is a totally new concept that I conceived a couple of years ago. I could only implement it with the use of titanium to make it trail worthy. The screen is supported by 3 feet. The design alows a "Laminar Flow" of air under it toward the burner. I hope to do my final testing tomorrow. Everything seems to be in place as far as components. I have the 2 cup Foster flat bottom pot with aluminum lid.I use a stainless steel wire pot support that fits the entire diameter of the pot for the most stable support. The burner portion is the Modified StarLyte with lid.

Total weight for the kit components so far is 67 grams or 2.3 ounces.

What do you think, still too heavy?


Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Titanium Windscreen Design on 01/18/2013 20:43:17 MST Print View

"What do you think, still too heavy?"

Are you using 0.005" thick titanium foil?

You are using the Fosters can to protect the titanium foil. Would there be any sense in using the titanium foil to protect the Fosters can?

--B.G.--

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Titanium Windscreen Design on 01/18/2013 21:03:53 MST Print View

Very interested to read how it works, what kind of boil times & efficiency you get. The weight is awesome.

How much clearance is there between the windscreen and the pot? Does the paperclip still work after it gets hot a few times?

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Titanium Windscreen Design on 01/19/2013 08:22:21 MST Print View

Hi Bob, yes I'm using 0.005 Titanium foil. I'm using the foster can for storage not protection. I used titanium because of the feet being subject to bending/breaking.

David, I'll start off with 1/8 inch between pot and screen and then go from there.

I can add a fuel bottle and cap to cover the pot and contents and store in a tyvek sack. That would bring it up to 3 Oz

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David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Laminar and turbulent flow on 01/19/2013 10:57:23 MST Print View

I think you're saying you've got laminar flow where it enters the bottom of the wind screen. If so (did you calc it, or do smoke traces?), fine. But just to be clear - you DON'T want laminar flow up the sides of your pot. The more turbulent that is, the better the heat transfer to the pot.

I've had good success increasing the heat transfer with small tabs on the vertical sides of pots. Mostly through increased turbulence (read up a little on vortex generators on airplane wings) rather than the tabs or fins functioning like traditional heat-exchange tubes.

Especially if you've got an identical Foster's can, try increasing its surface roughness with bits of foil, tiny tabs, etc. You may find a significant increase in heat transfer (if your Foster's can is mostly full of water). Ideally, the outside of the pot is rough and the inside of the windscreen is smooth. turbulence along the pot increases HX. More laminar flow along the windscreen decreases HX.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Laminar and turbulent flow on 01/19/2013 11:58:15 MST Print View

David Thomas, my design is based on the findings of Tony Beasely. He has some good information on laminar flow around pots and also lots of great photos made with "shadow graph" technigue. He created a thread over at my website:

http://www.bplite.com/viewtopic.php?f=41&t=816&p=46856#p46856

My windscreen design is aimed at preventing air from flowing downward over the top of the windscreen. Watch this youtube video I made back in 2009:

http://www.youtube.com/watch?v=a7mb-DU2sWY

The design is in it's infancy. Tests are being done today. The Foster pot has ridge lines around it so I suspect there will be turbulance but the windscreen will be in close proximity with the pot.

Thanks David for your insight on laminar/turbulant flow.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Laminar and turbulent flow on 01/19/2013 17:10:41 MST Print View

Here are the results of todays test using the new windscreen, modified StarLyte burner and stainless steel pot support.

I used 1/2 ounce of denatured alcohol throughout the test.
Water was at approx. 68-70 degrees
Air temp was 55 degrees in my green house.
Small plastic medicine cup was used to measure fuel
1/4 inch space between pot and windscreen. (Laminar flow was excellent, no radical movement of flame while burning. I am well pleased ;) )

The first test was just to see if the 2 cups would boil with 1/2 ounce of fuel no timing was done. It boiled and continued to burn for at least 1 min. From there I started to do the stop watch routine.

9:15 water boils, flame out at 11:00 min.

9:14 water boils, flame out at 10:45

8:30 water boils, flame out at 10:15

9:40 water boils, flame out 11:30

More testing tomorrow.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Laminar and turbulent flow on 01/20/2013 06:58:16 MST Print View

David Thomas, what did you think of Toney Beaselys' shadowgraph photos?

Here is a photobucket video that shows the flame pattern with 2 different air entry patterns on a simulated windscreen.

http://smg.photobucket.com/albums/v228/obijiwa/Frost%20Grabber/AAA%20YEAR%202013/?action=view&current=LaminarWindsreenTechnology.mp4


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Edited by zelph on 01/20/2013 07:12:57 MST.

John Donewar
(Newton) - MLife

Locale: Southeastern Louisiana
Re: Laminar and turbulent flow on 01/20/2013 07:30:53 MST Print View

"Especially if you've got an identical Foster's can, try increasing its surface roughness with bits of foil, tiny tabs, etc. You may find a significant increase in heat transfer (if your Foster's can is mostly full of water). Ideally, the outside of the pot is rough and the inside of the windscreen is smooth. turbulence along the pot increases HX. More laminar flow along the windscreen decreases HX."

@Dan,

The pictures in your post and the pictures on your website look different.

My Current Old Stock 2 cup flat bottomed Fosters pot

Are you using the "old stock" 2 cup flat bottom cans for your tests?

New Stock?

The new stock 2 cup flat bottom cans appear to have more ridges than the "old stock". Three ridges on the "old stock" and 5 on the "new stock".

Adding more ridges may make the pot stronger and increase the heat transfer as Dave suggests.

Man I really like that see through windscreen. It may not be practical for hiking but it sure is neat for testing purposes!

Party On,

Newton

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Re: Laminar and turbulent flow on 01/20/2013 10:13:23 MST Print View

"Man I really like that see through windscreen. It may not be practical for hiking but it sure is neat for testing purposes!"

Newton, I think transparency is what happens when he gets his titanium foil so thin.

--B.G.--

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Re: Laminar and turbulent flow on 01/20/2013 12:54:37 MST Print View

"Are you using the "old stock" 2 cup flat bottom cans for your tests?"

I'm using new atock. I have to upgrade my store photots. I had too many rejects in the original cans due to wrinkling of metal between ridges. It was cosmetic, didn't like the looks of it. 3 ridges makes the pot plenty strong. Did you notice the ridges/ruffles on the lid? The ruffles are new and will be on all lids shipped from this day forward. They fit nice and tight and allow steam to escape when it comes to full boil.http://img.photobucket.com/albums/v228/obijiwa/Frost%20Grabber/AAA%20YEAR%202013/titaniumkit005.jpg
If I use a glove I can squeeze the top of the can(while the lid is on) to lift it up and away from the windscreen. The pot support remains on the pot because it has a little tension on it that keeps it to the raised ridge of the can bottom. Comes off easy with a flick of a finger. In my tests I used a silicone pot grabber that works nice to lift the pot up. When I do a video I'll show how it's used.

Glad you like my transparent windscreen :-) A few years ago I was able to show how the flames go off from under a pot when you don't surround your pot completely with the windscreen. Bob is right, too thin and the Ti goes transparent ;) Yesterday as the light levels diminished while I was testing I could see little waves of flames causing the hot windscreen to glow red. The glowing red actually flowed with the flame movement, it was cool.

Tony Beasely says laminar is good and David says turbulant is good. So John, you agree with David. I'm not convinced yet. What I observed in my tests was laminar flow of heat up along side the pot/windscreen. I used a piece of tempered glass held above the pot so I could view the space between them. I could see flame moving very slowly, no turbulance. So without turbulance I was able to get great results with 1/2 ounce of fuel.

Todays tests will give me a chance to see how keeping the windscreen 1/2" distance away from the pot has an effect on boiling.

EDITED TO ADD: the windscreen has been heat treated to a high temperature so the "curl" of the ti when at rest is slighly larger than the diameter of the pot which makes it retain a "round" shape

Edited by zelph on 01/20/2013 13:01:12 MST.

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Turbulent flow on 01/20/2013 15:57:26 MST Print View

For high temperature gases, much of the heat transfer will be by radiant photons from incandescent gases - that's true in the visible range but more importantly in the infrared. In that regime, laminar or turbulent doesn't make much difference - consider view angles, reflectivity, etc to maximize radiant transfer to the pot.

But once the gases get to lower temps, wringing out the last heat is a function of convection of air and then conduction to the pot. Turbulent flow will greatly reduce the stagnant boundary layer which insulates the pot from the hot gases.

Ben Crocker
(alexdrewreed) - M

Locale: Kentucky
I would listen to David on 01/20/2013 16:24:50 MST Print View

As usual, David is making good sense. Its consistent with my education really heat transfer and fluid dynamics. With regard to flow entering the screen, I think the low entry is good to prevent gusts from causing strong air movement inside.
Have you ever tried a series of very small holes for air entering the windscreen? I would think small holes would dampen gusts and keep consistent airflow, which seems to be an important consideration. I would love to hear your thoughts and will test it myself too.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: I would listen to David on 01/20/2013 17:37:48 MST Print View

With homage to Zelph and the old adage that imitation is the sincerest form of flattery, I whipped out a clear windscreen from a Coleman lantern glass. Brilliant!

Tried Ben's suggestion for a lot of holes down low (104 holes @ 3/32" dia) and got good laminar flow in and up.Clear windscreen with laminar intake flow

Like Zelph, I'm not convinced that turbulent flow of hot gases up the sides of the pot is better than laminar. With turbulence some cold fresh air is getting mixed with the hot gases. Also, with laminar flow up the sides of the pot the hot gases stay close to the pot in a boundary layer, maximizing convection and radiant heat transfer. I will try some test burns using regular Foster's cans (smooth surface) versus my brushed finished Foster's cans (rough surface) to see if I can measure a difference.Brushed finish Foster's can

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: I would listen to David on 01/20/2013 18:06:44 MST Print View

David, I'm beggining to see more clearly now because you said "Turbulent flow will greatly reduce the stagnant boundary layer which insulates the pot from the hot gases." In the shadow graph photo that has the least amount of turbulance I can see the boundry layer next to the pot. I can now visuallize the boundry layers being in turbulance so that maximum amount of radiant heat is transfered. I'm convinced what you say is true. Thank you.

Ben, thanks for backing up what David said. I have tried small 1/4" holes in great quantity around the base and was not able to get enough oxygen. I had to increase the distance of the windscreen from the pot so air could come in over the top. I'll try a new approach and add 1/2" holes and keep the same 1/4" distance between screen and pot and see what happens. What I don't want to do is create a speedy updraft of hot gasses. Right now I'm getting my target fuel efficiency of 1/2 ounce of fuel per 2 cups of water.(65-70 start temp)

I did some testing today.
The last test I did I could see the red hot heat waves on my titanium windscreen. I did three tests and was able to boil 2 cups of 65 degree water with 1/2 ounce for all 3 tests. Sweet! Temperature in my greenhouse test area was 27 degreesF.

Here is alink to a youtube video that will show my last test.

http://www.youtube.com/watch?v=90DvxPGbEvE

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: I would listen to David on 01/20/2013 18:22:39 MST Print View

Well, rough surface definitely seems to perform better than smooth surface. Did four test boils with each pot. Air, 17 ml fuel and 500 ml water all at 58* F.

Average time for regular Foster's can = 4:56 min.

Average time for brushed Foster's can = 4:25 min.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: I would listen to David on 01/20/2013 18:46:18 MST Print View

Just after I did the three tests I also played with the glass screen and attached the 1/2" hole add-on strip. I was pleased with what I saw. I had the foster pot on the pot support with the modified starlyte under it. Very little flame extending over the edge of the pot.

Here is a video of it:

http://www.youtube.com/watch?v=aLkHnbFotp4

David Gardner, nice to have clear windscreens :-)))

How do you support your foster pots and do you have a photo or video of the flames going up the side of the pot using the glass windscreen?

If you put the pot directly on top of the beer bottle center how laminar are the flames going up the side of the Fosters'?

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: Re: I would listen to David on 01/20/2013 19:29:20 MST Print View

Here is a picture of the flames going up the side of the pot. Flow shows better on the right where the flame is in shadow. Looks very laminar, but the roughness of the brushed surface seems to make a significant difference in heat transfer.

The pot is supported by the center pedestal made from an aluminum air freshener bottle (the base is a 5.5 oz aluminum cat food can). The configuration of this stove creates one large flame all the way around, which flows in towards the base of the pot then out and up the sides.laminar flow

PS: Do you prefer to be addressed as Zelph or Dan?

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
An analogy on 01/20/2013 19:34:16 MST Print View

>I can now visuallize the boundry layers being in turbulance so that maximum amount of radiant heat is transferred.

Great. But a clarification: radiant heat transfer (by photons like visible and IR light), happens through and regardless of boundary layers. It is convective/conductive heat transfer that is effected so greatly by boundary layers.

Sometimes "dead air" or boundary layers are our friends and sometimes our enemies.

Let me give the reverse example - helpful boundary layers decreasing heat transfer:

When we think of "wind chill" we instinctive know that high speed wind makes for more heat transfer (cold winds cool us, convection ovens cook faster). Consider the layer of air nearest your skin. Define it as the air that moving between 0% (right at your skin) and 95% of the bulk air flow (the wind). That layer is the "boundary layer". Within the layer, there is laminar flow (each infinitesimally thin sub layer sliding, unmixed, past the adjacent sublayer). As such, heat transfer is slow, just like in the "dead air space" in your sleeping pad or down jacket. i.e. very little heat transfer. As the wind speed increases, the thickness of that boundary layer decreases significantly.

When everything is laminar, that layer is huge. At very high wind speeds, the boundary layer gets very thin and there is much more heat transfer (HX).

For HX to a pot, you can't generate high speeds (unless you do a very tall chimney). But vortex generators on airplane wings "energize" or stir the boundary layer without much drag. This can be as simple as little tabs, placed 20-30 degrees to the air flow. I've done that with the very sticky aluminum tape (the REAL duct tape - that one would use on a high-temperature duct) and it significantly increase efficient for very little weight.

Here's a video that's older than I am, but which I watched in my fluid dynamics class. Around 4:30, they give a good definition of boundary layer. There are great demonstrations of actual boundary layers under different conditions. It gets kinds of mathy, but crack a beer, and take another sip for every differential or integral sign they use. Try to follow the qualitative aspects of it and try to develop a better sense of the following concepts:

The "no-slip" condition at the walls.

Boundary layer thickness as a function of bulk velocity.

How the boundary layer varies over the length of a surface.

http://www.youtube.com/watch?v=wMxK2GtFFq0

Flame on,
David

Ben Crocker
(alexdrewreed) - M

Locale: Kentucky
fluid dynamics on 01/20/2013 20:07:46 MST Print View

David,you are a good teacher. I assume you do it for a living. If not,you should. You gave very nice descriptions of heat transfer.
And Dan and David, you guys are fast at the new experiments. My thoughts on the small holes was to dampen winds in the field where larger holes would let larger airflow in winds. You guys gave a good baseline on size that ought to show us what can work in windy or calm.conditions

Daryl Daryl
(lyrad1) - MLife

Locale: Pacific Northwest, USA, Earth
Re: An analogy on 01/20/2013 20:49:43 MST Print View

David,

I don't want to hijack this thread but after carefully reading your latest post I can't help but conclude that you are smarter, a lot smarter, than me. It reminds me of why I didn't major in any of the hard sciences in college.

Daryl

Nathan Hays
(oroambulant)

Locale: San Francisco
radiant heating on 01/21/2013 11:56:20 MST Print View

I think the heat transfer difference between smooth and rough cans could be attributed to reflectivity more than by turbulence. In all this discussion, no mention has been made of preparing the surfaces to maximize infrared heat transfer to the can. This includes the windscreen component.

To optimize, I would want a very IR reflective windscreen and absorptive pot. Flat black anodized pot.

I wonder if Ti performs worse than Al because of its poorer reflectivity (which it may not be at IR). And clearly (p.i.) the coleman screens don't reflect as well as Al.

I think these points completely dominate over turbulence/laminar concerns.

Ben Crocker
(alexdrewreed) - M

Locale: Kentucky
Radiant heat transfer on 01/21/2013 12:33:38 MST Print View

Nathan, you are no doubt correct that a flat black pot bottom can help efficiency. There was a prior thread that I know David was involved in that theorized and then tested that very premise. It was about a year ago. I painted the bottom of my Heine pot black with high temperature paint after that thread.

I continue to believe there is a significant amount of convective heat transfer as well. That's why jetboil has the fins. I know I read another thread that David was involved in too that showed some increase heat transfer when thin metal fins were added.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: radiant heating on 01/21/2013 13:12:29 MST Print View

Nathan,

Interesting thoughts.

If I understand you correctly, you think the main factor in the difference in boil times between a regular Foster's can and a brushed Foster's can is because the brushed can is more IR absorbing, rather than the surface roughness. Not sure how to verify empirically. I could buff and polish the can pot so it is shiny and reflective, but that would also make it smooth.

I have spoken to an anodizing company and they can't do a can that has not been emptied. They also cautioned that the anodizing process uses some fairly nasty chemicals that must not be consumed but which would be deposited on the inside of an empty can. I have an appointment with them tomorrow morning to see if they can even do something as thin as a beer can. If they can do it I will get at least one can anodized for experimental purposes.

Painting flat black is easy, and I tried that in early experiments....didn't seem to make any difference. However, I will try it again under more controlled conditions.

Will also look into other processes by which bare aluminum can be blackened.

Will try polishing the inner surface of a windscreen too, to see if increases IR reflectivity. I use stainless steel and titanium for windscreens, so I will try one of each.

Do you know if Ti performs worse than Al as a windscreen, and are wondering about the cause, or are you wondering if Ti actually does perform more poorly than Al for that use?

Nathan Hays
(oroambulant)

Locale: San Francisco
Re: radiant heating on 01/21/2013 14:09:43 MST Print View

Check out Caswell for diy anodizing. I'm sure you could make a rig that only anodizes the exterior. Not sure if it is worth the effort. That said, paint doesn't conduct heat so well and it is heavy...

I only just became interested in myostoves (and made 5 different types in an afternoon - love it!) I'm moving on to the windscreen/support, so no knowledge as yet of the difference between Ti and Al wrt IR reflectiveness.

I'm keen on building an accurate test setup that measures heat transfer in degrees/minute, not just boil times. It needs to have a consistent heat source so I'll use a cannister stove and let everything stabilize before I track the temp rise.

I think it goes like this: Set it all up with cold water, then let the temp rise to 100 F and track time to 200 F. Needs to be stirred while rising to prevent convective hot spots, etc..

Gary Dunckel
(Zia-Grill-Guy) - MLife

Locale: Boulder
Ti vs. Al winscreens on 01/21/2013 14:26:58 MST Print View

I would expect that a titanium wind screen would hold the heat better than aluminum, due to its poor heat conductivity.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: radiant heating on 01/21/2013 14:36:15 MST Print View

Will Reitveld, a contributor here on BPL, uses a digital thermometer and digital scale to calculate degrees/minute. His typical test protocol is 500 ml of water and 14 grams of fuel, with water, fuel and air temp all the same and usually cool(40* F - 50* F) to simulate real world conditions. Don't know if he stirs too.

Figured out a way to blacken the outsides of the cans without using any chemicals or paint. Will try some test boils later. I use a meat thermometer and measuring cup, so it's not as accurate as digital, but close enough I think for comparisons and reasonably accurate calculations.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Ti vs. Al windscreens on 01/21/2013 14:52:43 MST Print View

"I would expect that a titanium wind screen would hold the heat better than aluminum, due to its poor heat conductivity."

Gary, why can't you make a windscreen out of titanium wire with a cover of aluminum foil?

--B.G.--

Edited by --B.G.-- on 01/21/2013 15:03:51 MST.

Ben Crocker
(alexdrewreed) - M

Locale: Kentucky
Stoves on 01/21/2013 15:46:11 MST Print View

Here is an older post I referenced above that dealt with some of the same issues:

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=58270&disable_pagination=1

I thought it had some pretty good info.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Titanium Windscreen Design on 01/21/2013 16:21:58 MST Print View

Ok, we're back to the titanium windscreen guys.

I added some 1/2" holes and burned some wood in it. I put about 2 hous of actual burn time in to test for strength and it's ability to retain it's shape. All went well.

After the wood test I went ahead and turned it upside down and tested a few esbit cubes in my esbit burner (esbitmizer). I'm able to place the pot onto the support and then put the windscreen in place. Once they are ready I put the cube into the esbitmizer, light it and slide it under the windscreen into place. The lid of the burner stays attached and I'm able to slide it out if I want to reduce the flame height to simmer or snuff it out. If I snuff it out I can let the pot sit on the support with windscreen around it till I'm ready to use the water.

http://www.youtube.com/watch?v=OsUx4P0tWNs

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: radiant heating on 01/21/2013 18:40:24 MST Print View

So I read the prior threads regarding painting the can pot bottoms black and putting fins on. I blackened a couple of pots by boiling them - whatever is in the tap water here reacts with the bare aluminum and blackens the cans very effectively.water-blackened can

Boil tests did not reveal any improvement from blackening the cans. Did three test boils using 500 ml of water and 17 ml of fuel with air, fuel and water all at 60* F. Average time to boil plain brushed can = 4:26 min. Average time for blackened cans = 4:35 min.

Tried adding fins at the can base, angled at about 30 degrees to the vertical axis.side view can with finsbottom view can with fins

Surprisingly, the boil times were measurably longer with the fins. Average of 3 boils under the same conditions was 4:53 min. Messy as heck too. The adhesive on all of the fins burned off.fins after burning

I'm going to stick with plain, brushed pots. Seems to work the best and certainly is a lot less work than blackening and finning.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Titanium Windscreen Design on 01/21/2013 20:39:56 MST Print View

I added some 1/2" holes and burned some wood in it. I put about 2 hous of actual burn time in to test for strength and it's ability to retain it's shape. All went well.

After the wood test I went ahead and turned it upside down and tested a few esbit cubes in my esbit burner (esbitmizer). I'm able to place the pot onto the support and then put the windscreen in place. Once they are ready I put the cube into the esbitmizer, light it and slide it under the windscreen into place. The lid of the burner stays attached and I'm able to slide it out if I want to reduce the flame height to simmer or snuff it out. If I snuff it out I can let the pot sit on the support with windscreen around it till I'm ready to use the water.

http://www.youtube.com/watch?v=OsUx4P0tWNs

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Boy toys on 01/21/2013 21:49:54 MST Print View

DavidG:

If you need something for your late Christmas list, add an IR thermometer. My first one was $150, but they are $30-ish now. Look at ebay, J C Whitney, etc.

Here's the take-home message (I learned this from the first human to (1) quantum-entangle more than 2 photons and (2) find an exception to the Heisenberg Uncertainty Principle - my wife and I each have brothers smarter than ourselves): clean metal surfaces are MIRRORS to infrared radiation. That is bad, because heat your pot could absorb will be be reflected away.

With your spiffy, new, IR thermometer in hand: fill your pot with hot water. Check its "temperature" with the IR thermometer. If it is a "blackbody" (good), then it will read the water temp. If it is reflective of IR radiation (bad), it will read room temp. Maybe your treatment made it "black" in the infrared. But maybe not. Test it compared to actual black paint (BBQ grill paint or auto-parts-store paint for an engine block are both high-temp paints). Look at my tests from 13 months ago and I found that white, black and red paint were all "black" in the infrared.

The tabs seemed too big and too low. Big because you're trying to energize only the air film very close to the pot. Low because they were in the very hot gases. You want to "stir up" the somewhat cooler air. I'm guessing there was still a visible flame at that point (most HX was visible+IR radiant transfer) and therefore, the IR radiant HX continued further up the pot. Also, if those tabs fit within your windscreen, your windscreen could be a fair bit smaller. I'd guess you are diluting the flue gas temps with excess ambient air and that will definitely hurt HX.

One approach is "time to boil". That's good but subject to a lot of variables (room temp, stove temp, water temp, etc). Exhaust gas heat is another thing to monitor. If exhaust gases are small in flow rate and cool in temperature, you have captured more heat from them.

But a few careful experiments can often blow the best theories right out of the water.

-David

jeffrey armbruster
(book) - M

Locale: Northern California
"Titanium Windscreen Design" on 01/21/2013 21:59:12 MST Print View

Who cares about boil times in a beer can: tell us more about the exception to the Heisenberg Uncertainty Principle!

Edited by book on 01/21/2013 22:10:14 MST.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Boy toys on 01/22/2013 00:12:03 MST Print View

David Thomas,

Groan. I'm not even done paying for the holidays yet, but I can see I've still got shopping to do.

Thanks for the thought-provoking comments.

I'm empirical and Edisonian in my approach. I studied hard sciences in college and have an engineering background so am generally familiar with the theoretical side of things. But I test and verify because practice/reality has an uncomfortable way of throwing unknown variables into the mix.

I've tried the BBQ and black engine block paint, but dozens of test boils did not reveal any advantage to it in terms of faster HX or greater fuel efficiency, at least not with the paint I used. Perhaps the paint acts as an insulating layer, perhaps the top part of the can radiates heat more rapidly than when it is shiny, perhaps it's something else. The IR thermometer will help sort that out. What I can say for sure is that the brushed cans I tested heated more rapidly from the same heat source than unbrushed cans, painted cans, or water-blackened cans I tested.

I use frustum windscreens, so the base is wider than the top. At the top the windscreen is about 1/4" from the can. I will try smaller and higher fins.

I will also try polishing the inside surface of a windscreen, to see if it reflects a measurable amount more heat back into the can.

I'd really like to try putting a ridge like Zelph's cans about 1/2" above the top of the windscreen to see if the ridge jutting into the stream of exhaust gases captures more heat, but I don't have the tools yet. More items for the shopping list.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Boy toys on 01/22/2013 07:17:47 MST Print View

At the end of the day and we put all our boy toys away we can look back and say we've tried out best for today. Tomorrow will be better. :-)

I'm completely happy when I can get an alcohol stove to boil 2 cups of 65-70 degree water using 1/2 ounce of denatured alcohol.

David Gardners' brushed cans have been brutally stripped of their protective coating allowing them to be exposed to the harshness of exhaust gases, the elements and greasy grimey hands. The brushing also removes aluminum from the very thin wall. Life of the can is diminished.

Way back when, in the days of "radiators" to heat our homes with water it was said not to paint the surface of them. Painting reduced their emisivity or ability to radiate heat. So if it prevented heat from going out I would also think it prevents heat from coming in. Let your cans be as is.

We should keep in mind how small of an item we are working with in terms of heating. Gee whiz, you guys are extreme. Be happy with your stoves that boil 2 cups with 1/2 ounce of fuel. There are so many DIYselfers out there that get freaked out when they read all this stuff about the quantum theory of alcohol stoves and the miricals of Titanium.
The Modified StarLyte burner has a lot of merit when it comes to heating in a confined space, controling the release of vapors. David Gardners' stove on the hand has a lot of open space and the fuel burns in a radical fashion just like a Supercat stove made with a Fancey Feast cat food can. As we know, the Supercat stove can heat 2 cups of water with 1/2 ounce of fuel in 4-5 min.

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Uncertainties. on 01/22/2013 09:22:48 MST Print View

>Who cares about boil times in a beer can: tell us more about the exception to the Heisenberg Uncertainty Principle!

Jeff: While at UC Berkeley I caved with a physics grad student. He later brought his sister along on our annual gourmet BPing trip. I brought ice cream sundaes and a hot tub 6 miles in on that trip (had some Sherpas to help). He went on to a professorship at Spain National Physics Institute. His sister graduated med school, we married, and moved to Alaska.

An overview: http://physicsworld.com/cws/article/news/2011/mar/24/quantum-probe-beats-heisenberg-limit

An excerpt: . . predicted that the Heisenberg limit could be beaten by introducing nonlinear interactions between the measuring particles. That prediction has now been shown to be true, thanks to an experiment carried out by Morgan Mitchell and colleagues at the Institute of Photonic Sciences at Barcelona. Mitchell's group fired laser pulses into a sample of ultracold rubidium atoms held in an optical trap and measured how the atoms' spin angular momentum caused the polarization axis of the photons to rotate.

jeffrey armbruster
(book) - M

Locale: Northern California
"Titanium Windscreen Design" on 01/22/2013 10:14:01 MST Print View

Well thank God that's cleared up! I was betting on death or taxes, or both. I'm glad that no imaginary cats were harmed in these experiments. I work near Cal, so here's a shout out from your old digs.

John Donewar
(Newton) - MLife

Locale: Southeastern Louisiana
Re: Uncertainties. on 01/22/2013 10:34:01 MST Print View

And we thought that The Quest for Fire was complicated.

Whew!

Equals Fire

Does anyone remember the KISS principle? Keep It Sublimly Simple.

Fuel goes into stove. Stove is lit. Water goes in pot. Put lid on pot. Pot goes above flame. Windscreen goes around stove and pot. Water boils a little later.

Hint: Do not watch the pot. ;-)

What have we learned from all of this discussion? Raise the windscreen 1/2" to 3/4" or use either large draft holes or rectangular draft vents on the bottom of the windscreen to keep the stove's flame stable and under the cook pot.

30 seconds here or there won't really matter. If it does carry a canister stove and be done in half the time or less.

@Dan,

You have burned more alcohol, wood and Esbit tabs than any 100 people I know. You're always looking for new, lighter and more efficient ways for us to boil water. I am impressed by the way you share your knowledge with do it yourselfers. Thanks for the continued experimentation. Please don't stop.

Party On,

Newton

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Re: "Titanium Windscreen Design" on 01/22/2013 10:37:15 MST Print View

>"no imaginary cats were harmed"

LOL.

His research group has adopted a logo of a kitten and a rubidium atom. Playing on the same joke.

Nathan Hays
(oroambulant)

Locale: San Francisco
fins results on 01/22/2013 15:55:06 MST Print View

It seems clear from the smoke trails off the fins that the fins sapped heat out of as-yet-uncombusted gasses which then condensed on the can. In a jetboil, the gas is all burned before it gets to the fins, or at least is not cooled enough to prevent full combustion. I think you definitely do not want the fins in the flame.

One thing I've thought about is how in the jetboil burner there is a screen which gets white hot. I think this screen may serve to ensure any poorly mixed or cooler gasses do reach ignition conditions. I wonder if such a device would help pressurized stoves light more easily - my biggest beef with the penny. I'll be trying tonight...

Complete burning of the fuel is the first step to efficiency, followed by transference to the pot/water.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: fins results on 01/22/2013 16:38:05 MST Print View

The smoke trails on the finned cans are from the burned aluminum duct tape adhesive.

Will definitely try fins higher up, out of the alcohol flames. Will try one with fins at an angle and another with fins vertical.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
I'm on the right track on 01/22/2013 18:25:31 MST Print View

I think I have the right pot with many ridges on it that could muster up lots of turbulance with the gases traveling upward between the windscreen and the pot. Take a look:

photobucket video, click on it.
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I was able to do a video today to kinda recap how I can use the windscreen in the wood, alcohol and esbit modes. I had to divide the video into 2 parts.

http://www.youtube.com/watch?v=9sVimCy5Rmg (1st part)

http://www.youtube.com/watch?v=2j7Rz59l9eA

The windscreen held up very well under the high heat of the wood fires. The stainless steel clips did also as did the three pot support extensions.

Tomorrow I'll do some tests with Esbitmizer in the alcohol mode to see how well it does with 1/2 ounce of fuel. I'll also do more wood burning with the windscreen to test an idea that I have for an integrated clip system to keep the screen closed so I can eliminate the stainless clips. I'm partial to the Keep it Sublimely Simple principle of John D.

John, I'm always glad to share ideas. Stove designing is really an interesting hobby and science. Stoves are fun. I saw some of my photos of how I roasted hot dogs using the Venom Super Stove. I wrapped some hot dogs with non stick aluminum foil and stuck them into the center of the stove and lit it. The flames went up the side of the foiled hot dogs and they roasted really nice using 1/2 ounce of fuel.

I'm on the right track ;)

Edited by zelph on 01/22/2013 18:27:34 MST.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: I'm on the right track on 01/22/2013 18:29:40 MST Print View

"non stick aluminum foil"

What the heck is that? Or, where do you get it?

I've never seen anything called that.

--B.G.--

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: I'm on the right track on 01/22/2013 19:30:35 MST Print View

Bob, your local grocery store should have it. Ask an associate for help.

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Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Re: Re: I'm on the right track on 01/22/2013 19:54:17 MST Print View

"Ask an associate for help."

Can't do it, Dan.

I am fluent only in English. They aren't.

--B.G.--

Nathan Hays
(oroambulant)

Locale: San Francisco
Right track on 01/22/2013 20:26:02 MST Print View

Zelph - I like the ribs. I bought some nylon sliding shower door wheels with bearings today to make a bead roller. Two flats and one rounded. Will post if they work. The video with the peen-beanie everyone refers to looks ok, but I wanted something I could expand to making my own rolled edges. It would be keen to double roll a new edge instead of needing a machined ring, no?

Still waiting for Ti foil to arrive. Cutting up a turkey pan for tonight's lab work.

Has anyone tried to re-form polyethylene containers? I'm looking to stretch out a ziplock screw top to accommodate a full length fosters pot.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Right track on 01/22/2013 20:44:54 MST Print View

Bob, wing it!!! or you're SOL

Nathan, get the wheels rollin and go for it. Everybody and their uncle wants to make the ridges. Local grocery stores have nice plastic containers for full size foster cans. Look in the canning section for Kosher Pickling Salt or in the cleaning supply dept. for mr Clean or Klorox wipes.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Right track on 01/23/2013 10:04:23 MST Print View

Nathan,

I haven't tried re-forming polyethylene. However, 16 oz and 8 oz "Delitainers" (available through Amazon or at your local deli) press fit very snugly and securely to the 1 qt Ziploc food containers. Light and inexpensive too. 16 oz delitainer8 oz delitainer

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Sidetracked on 01/23/2013 21:32:31 MST Print View

The question came up on another forum on how to have a small wood fire on snow or ice and wet ground. What would I use to insulate under the stove.

I've never had to do this so I gave it some thought and decided I would first gather some 1" diameter branches of 12" long and lay them flat on the above the surfaces to make as flat a surface for the stove as I could. I would then lay down a 1/8" sheet of Viton onto the branches to form a stable surfac On top of the viton I woul lay a sheet of .002 Titanium or stainless steel. On top of the aI would put my wood burner.

I did one test burn of the above procedure and it worked well. The Viton scorched but did not burn. It warped in the center but flattened when it cooled. The stove I used had a steel grate 1/2" away from the stainless sheet thet the stove rested on. I burned enough wood in the stove equivelant in quantity to boil 6-8 cups of water.

What would you use under the same scenario of winter wood stove use?

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: Sidetracked on 01/23/2013 22:28:30 MST Print View

I don't think I would bother with the Viton layer.
If you insist, substitute teflon/glass canveyor fabric.

Cheers

Eric Blumensaadt
(Danepacker) - MLife

Locale: Mojave Desert
And After All Of This... on 01/25/2013 15:04:58 MST Print View

...one can see why Caldera Cones work so very well.

Very enlightening discussion. Explains JetBoil and Primus pot-bottom fins too.

David Thomas
(DavidinKenai) - MLife

Locale: North Woods. Far North.
Re: Sidetracked on 01/26/2013 00:31:55 MST Print View

Dan,

For an insulating base, I like your idea of wood interspaced with Ti. If you have sheets of Ti laying around.

But if not, I've had good luck just building a thick base of wood - much as you describe: 1" diameter-ish lengths, but layer upon layer at right angles to each other.

When I built campfires on top of such a base (actually 2+" diameter sticks), they were still burning the next morning. A foot deeper into the 10-foot snow base, but still burning.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Back on Track on 01/26/2013 14:22:27 MST Print View



Bob Gross you were right. I changed my mind and will protect the can with the windscreen ;-)

I've also decided to move my 1/2" holes up 3/8". They have a little pucker at the bottoms edge. Also my closure for the windscreen is going to be a fixed band that will allow me to keep it nice and simple. It will help to keep the windscreens' shape in the "round" It will be fastened to the screen with an eyelet.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Back on Track on 01/29/2013 17:41:47 MST Print View

DavidT. I had some 5" wide by 3/16" thick fiberglass cloth that I cut to 10 long. I then sprayed the cut ends with high temperature stove paint to prevent unravelling. worked good.

I've completed my windscreen design. I've created a grate out of Ti and stainless steel. The windscreen is designed to stay within a 1/4" of the pot when in the alcohol mode and in the wood mode it is 3/8" from the pot. In the wood mode the Foster pot will sit on top of the "V" shaped stainless steel pot support. Much larger diameter pots can be placed on the 3 large pot supports that are integrated into the design of the windscreen.

I'll use the modified StarLyte burner when in the alcohol mode and the Esbitmizer when I want to use esbit.

The 2 piece grate stores nicely under the bottom of the pot. They are held there with a plastic lid for storage.

The pot that you see in the photo is for maximim strength and water capacity when used in the wood burning mode. (My preference) I like burning wood. I have a tyvek stuff sack for storing everything.

The windscreen never has to be disassembled. It fits snugly up against the pot. When you burn wood it makes no sense to want to put your windscreen inside your pot.

I'll get more photos and specifications posted here tomorrow.

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Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Titanium Windscreen Design on 01/30/2013 20:37:25 MST Print View

The Titanium windscreen/stove, grate system, V shaped pot support, plastic retainer ring, Foster 3 cup Flat Bottom pot and Tyvek stuff sack weigh in at 2.8 ounces/ 79 grams

Fire box size is 4" diameter x 3.5" high

6-8 inch diameter pots are supported on the 3 extending pot supports. Those pot supports can be seen in one of the above videos.

Tomorrow I'll show the windscreen, alcohol stove, esbit stove and pot support in a video.

What we have here is a wood burning stove, 3 cup pot and stuff sack. Watch the video.

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Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Re: Titanium Windscreen Design on 01/31/2013 20:53:40 MST Print View

Everything revolved around the Ti Windscreen and so I gathered up items to include in a kitchen.

Choice of Foster pot with lids
Combination Titanium Windscreen
Modified StarLyte burner with lid for ultimate alcohol efficiency.
Esbitmizer for use with esbit. Has simmer ability.
Esbit cubes and alcohol fuel bottle.
Grate set-up and "V" shaped pot support for windscreen in wood burning mode.
Stainless steel pot support for alcohol and esbit burning mode.
Silicone pot grabber.
Tyvek stuff sack.

Photobucket video

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</center>

todd harper
(funnymoney) - MLife

Locale: Sunshine State
Re: Titanium Windscreen Design on 02/01/2013 16:57:16 MST Print View

Wow Zelph,

That's one sweet setup!!!! And impressive weight too. What's the cost?

One question I've wanted to ask about the flat-bottom pots: Are they as durable as stock cans? I was concerned about the weld/joint being a weak spot.

Thanks,
Todd

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Better than Caldera Cone on 02/01/2013 19:36:26 MST Print View

Thank you Todd, glad you like it. It is evolving very nicely. I'm taking my time, making sure everything is tested well. I moved the 1/2" holes upward a tad so now I have to redo my tests in all modes.

The flat bottoms on the Fosters are just like "factory" sealed and are guaranteed to be as durable as stock cans. If one should fail for some reason, send it back for a replacement or full refund.

The Titanium Windscreen design is better than the Caldera Cone. It's under no tension, ready to go once taken out of the stuff sack. Will not spring out and bite you;-)No assembly or disassembly. The grate system is lighter. One of the things that BobG pointed out is why use the Foster Pot to protect the titanium windscreen. He's absolutely right. Store it outside the pot. Calder Cones are always depicted as storing in the pot. If the windscreen/wood stove is used in the fire mode I don't want it stored in the pot.

This kit will be used in the wood fire mode. I'm big on wood fires. Alcohol and esbit as back-ups.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Better than Caldera Cone on 02/02/2013 21:07:09 MST Print View

I had to make a change in the grate. didn't like the 2 pieces. Then I had to add a storage container for the grate.

How do you like it so far?

Photobucket video. Click on it to view

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</center>

Edited by zelph on 02/02/2013 21:08:36 MST.

Backpack Jack
(jumpbackjack) - F - M

Locale: Armpit of California
Re: Re: Better than Caldera on 02/02/2013 22:47:31 MST Print View

When will they be ready to buy?

M B
(livingontheroad) - M
foster on 02/02/2013 23:43:59 MST Print View

love my flat bottom foster pot.

But I have rust appearing in the bottom seam in spots where the coating on the steel bottom has failed. Not a big issue mind you. Just points to room for improvement. Like a TI bottom maybe?

Getting close to my tealight setup with my pot. 2.0 oz. 1.62 if use tent stakes thru an Al windscreen to support the pot. boils in 7.5 min.

I dont find Ti foil is necessary at all. In fact doing the math, I find zero benefit from it unless use .002, and even then its only like .1 oz. Not worth the cost.

Edited by livingontheroad on 02/02/2013 23:51:15 MST.

Karple T
(ctracyverizon)

Locale: Mid-Alantic
"Titanium Windscreen Design" on 02/03/2013 10:23:10 MST Print View

Brilliant !!! - Take my money ... Please.

Put me on your list for the first run!

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: "Titanium Windscreen Design" on 02/04/2013 19:30:48 MST Print View

Thanks MB and Craig, glad you like it.

I did test 1 of 3 tonight. I'm testing for durability of the stainless steel grate and the ability of the windscreen to withstand high temperature and have no warping occur.

I'm well pleased with this Titanium technology. 1st test was a success, no warp and welds help up nicely on the grate.

This is a photobucket video, click on it to view:

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MB, this ti that I'm using is .005 and is tough stuff for the windscreen to function as a wood burner also. No warping after use so that when used for alcohol it is nice and round for even distribution of heat going up the sides of the pot. As we now know, the ridges on the Foster can create turbulance which is good for maximising heat transfer.

More tests tomorrow. Thanks for your comments.

Anyone else out there making a windscreen out of Ti?

Backpack Jack
(jumpbackjack) - F - M

Locale: Armpit of California
Re: Re: Better than Caldera on 02/04/2013 20:30:56 MST Print View

Dan,

When ever they're ready to be sold I'll take one.

I love the design and simplicity, I already have your Starlite stove and love it, can't wait until these are ready.

Eric Lundquist
(cobberman) - F - M

Locale: Dry side of the Eastern Sierra's
Re: Re: "Titanium Windscreen Design" on 02/04/2013 20:39:19 MST Print View

Anyone else out there making a windscreen out of Ti?

Suluk46 and qiwiz both make a titanium windscreen. Different designs though.

EDIT: Forgot about LiteTrail. They've got a Ti windscreen as well.

Edited by cobberman on 02/05/2013 09:39:28 MST.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Re: "Titanium Windscreen Design" on 02/05/2013 07:08:47 MST Print View

I'm working on this as fast as I can. Yesterday I had a plumbing project that took up most of my day. Members are adding great information. I'm changing the design as the info comes in. Little things mean a lot. David Gardner suggested roughing up the surface of the Foster can. If I brush the surface of the Foster cans I can increase speed in boiling. I'll do that to day and include those in my retesting of the stove in the alcohol mode. Raising the holes a short distance from the bottom of the windscreen eliminated the puckering that occurred while in the wood burning mode. I'll brush a few cans to see how they work out. Thanks David G.

Because I created a wide stainless steel pot support I am now able to use aluminum bottoms on the pots. So what we have up to this point is flat aluminum bottom pots with ridges and brushed surface for maximum heat transfer and speed of boiling. Makes me think of fast food restaurants on the trails. Instead of going inside to eat we go to the "fast" drive through:-))) At times I forget there are speed hikers out there wanting to complete the hike in the fastest time possible.

More testing and making of the stainless steel pot supports. That will bring me closer to finished kits.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Brushed with Ridges on 02/05/2013 09:49:44 MST Print View

I brushed one up and added a few more ridges for extra turbulance. That should be able to suck in a lot of heat.

2.5 cup capacity, flat bottom Foster can brushed/w ridges, aluminum bottom and lid weighs in at 22 grams.

This can weighs 22gr Has aluminum bottom and lid and has the ridges.

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</center>

EDIT:
Eric, thanks for the links. I was more interested if there were any DIY windscreens in progress. A while back someone had a really complicated one in the works. I'll see if I can find it.

Edited by zelph on 02/05/2013 09:55:53 MST.

Eric Blumensaadt
(Danepacker) - MLife

Locale: Mojave Desert
"Better" than Caldera Cone?? on 02/05/2013 16:15:57 MST Print View

Maybe a teensy bit faster to deploy than a CC but I'll bet money it's definitely NOT better in heat efficiency than a Caldera Cone.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: "Better" than Caldera Cone?? on 02/05/2013 17:45:59 MST Print View

It's better IMHO.

Richard Cullip
(RichardCullip) - M

Locale: San Diego County
Dan - I've made one on 02/05/2013 18:11:24 MST Print View

Dan - I've made a Ti (.005" thickness) windscreen designed around the wide 900ml Ultralight Ti Evernew pot and your Fancee Feest stove. Criteria was for the windscreen to roll up and fit inside the pot complete with stove and fuel bottle. It works well for me


Ti windscreen

Fits in 900ml Pot

Edited by RichardCullip on 02/05/2013 18:16:02 MST.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: Re: Re: "Titanium Windscreen Design" on 02/05/2013 18:37:59 MST Print View

Very interested to see if brushing works well for you too, and especially with the ridges.

Tried to upload a photo of a conical windscreen I make with .005" Ti from Titanium Goat, but the "Insert Image at Cursor" button doesn't seem to working right now. Will try again later. Used the Zen Stoves cone designer software - sweet.

I've found that .003" stainless steel works well too, weighs only a couple grams more (24.6 vs. 22.1 for this particular design), and is a lot less expensive for the material. Doesn't have nearly the coolness factor, but it polishes to a mirror-like finish on the inside to reflect more IR back into the pot. Another thing I'd like to test to see if it makes a measurable difference.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: "Titanium Windscreen Design" on 02/05/2013 18:52:13 MST Print View

Here's that picture of my titanium cone windscreen for use with beer can pots.Ti Cone

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Dan - I've made one on 02/06/2013 17:52:48 MST Print View

Hi richard C. your windscreen looks like it should work well. You are the first I've heard of to be useing the Fancee Feest stove in a cone. Dose the pot sit on the stove? I can see the change of color caused by heat concentrates near the pot handle cut-out. I suspect that is true with other cones made for your type of pot. Anyone out there have the same heat pattern on their Ti windscreens made by Trail Desings?

I finished my wood burning heat tests today and all went well.

I welded up a batch of SS pot supports. I made a change in the design. I made them full circle for maximum maximum pot support. Pot support is now the same diameter of the pot bottom. The little ridge on the bottom of the pot prevents the pot from sliding off.

The pot support and a StarLyte burner together weigh in at 17 grams.

Brushed aluminum, flat bottom pot and lid weigh 22 grams

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Richard Cullip
(RichardCullip) - M

Locale: San Diego County
Re: Re: Dan - I've made one on 02/06/2013 22:46:18 MST Print View

Yes my pot sits on the stove. It's not supported by the windscreen. I like the setup for boiling water for Freezer Bag Cooking. Here's a view without the windscreen:

Here's the pot supported by the stove

Kevin Beeden
(captain_paranoia) - F

Locale: UK
Re: Dan - I've made one on 02/07/2013 05:47:05 MST Print View

Richard,

Very nice-looking clone. Well done!

Did you have any trouble folding the tabs, as I've found Ti is more fragile than Al, since it's nowhere near as ductile? I usually recommend making Ti tabs narrower, or splitting them in two.

Edited by captain_paranoia on 02/07/2013 05:50:24 MST.

Richard Cullip
(RichardCullip) - M

Locale: San Diego County
Re: Re: Dan - I've made one on 02/07/2013 19:33:36 MST Print View

Thanks Kevin. I couldn't have made it without your cone design script. I was a bit worried about folding the tabs in the Ti foil but didn't have any problems with them once I actually did them. I just used a small scrap piece of the Ti foil as a spacer and bent the tabs over that.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Re: Dan - I've made one on 02/07/2013 20:15:35 MST Print View

What alloy of Ti are you guys using that you can bend it over like that?

I had to put this project on hold for a couple of days to process 144 Foster cans. I ran out of 2 designs. Got to play catchup now.

Richard Cullip
(RichardCullip) - M

Locale: San Diego County
Re:Dan - Don't know the specific alloy on 02/07/2013 21:10:26 MST Print View

Dan - I don't know the specific alloy. I got my Ti Foil (.005") from Titanium Goat and built my windscreen from that Ti Foil. It's pretty springy stuff. I have to be careful when I roll it up for storage. It wants to spring open so I'm careful to keep my fingers safe from sharp edges in case it slips and springs open. I roll it tight enough to fit inside the Fancee Feest stove and then my fuel bottle goes inside the rolled up windscreen and it results in a neat compact pckage that fits inside my 900ml wide Evernew Ultralight pot.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Re:Dan - Don't know the specific alloy on 02/07/2013 21:29:44 MST Print View

"I have to be careful when I roll it up for storage. It wants to spring open so I'm careful to keep my fingers safe from sharp edges in case it slips and springs open."

You might want to check out the method that Trail Designs uses when they ship a Sidewinder. They roll the titanium up and slide that into a Tyvek sleeve, and the sleeve is stored inside the cook pot. This is a round paper/cloth tube, so it doesn't weigh much. The rolled titanium can't really jump out of that.

--B.G.--

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Wants to spring open on 02/07/2013 22:54:21 MST Print View

I had that occur when I unpacked an aluminum cone while making a video. Got to remember that they are under tension. That tension issue was a concern for me when I designed this new windscreen. I releived the tension by heat treating. You can see from my last video that there is no longer a concern of a "jumping out" issue. I consider that a major improvement over the DIY or commercial cones.

Watch the video:

http://www.woodgaz-stove.com/ridgeline-can-for-caldera-cone-keg.php

By the way, the stainless steel band closure strip that helps hold my windscreen together is in part an idea that Jason Klass came up with a few years ago. I think he called it a belt buckle closure. It had quite a few holes punched in it to reduce weight. Thanks Jason :-)

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Project on hold on 02/09/2013 07:07:30 MST Print View

Family matters have caused me to put this project on hold.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Project on hold on 02/09/2013 11:54:47 MST Print View

Dan, sorry to hear it. Hope everything works out OK.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Re: Project on hold on 02/14/2013 19:26:55 MST Print View

Thanks David. Son-in-law's funeral was yesterday. He was 54 years young. Heart attack/diabetes. Now life goes on for the rest of us for a space in time. Make the best of it.

I can begin my project again tomorrow.

brent driggers
(cadyak) - MLife

Locale: southwest georgia
condolences on 02/15/2013 11:00:17 MST Print View

Very sorry to hear about your son-in-law.

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: condolences on 02/16/2013 16:44:12 MST Print View

Thank you Brent. Really takes a toll on a guy. Takes the wind out of your sails for a bit.

Hey, just wanted to get back on track with this project. Want to show you how I pack the stove in the wood burning mode. after you watch my video go over and watch the Trail Designs video on how the TiTri Inferno stove is loaded. Big difference in the two.

Watch "User Friendly" (click on it)

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Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Project is Finished on 02/20/2013 12:38:58 MST Print View

I'm finished with this windscreen project. All has went well. Working with titanium has been interesting and rewarding.

New design for a welded wire pot support gives new meaning to a StarLyte stove. Yesterday I weighed a 2 cup foster pot with lid, a starlyte burner with lid and a full size ss pot support and the weight came to 1.5 ounces. Pot support fits inside the Foster can.

Thank you everyone for your help on this project.

Roger Munsey
(8100LT) - MLife

Locale: Midwest
Just ordered mine! on 02/28/2013 10:41:22 MST Print View

Dan,

Thanks for your work and videos on this project.
I just ordered this new kit from you and it looks like
you shipped already! Can't wait to try it!

Roger

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Just ordered mine! on 02/28/2013 20:09:56 MST Print View

Yes, thank you. I shipped it out yesterday. Send me an email when it arrives, I have a question for you.

Roger Munsey
(8100LT) - MLife

Locale: Midwest
Looks Great! on 03/01/2013 19:35:21 MST Print View

Dan,

Kit arrived and it looks great!
Sent you a PM.

Roger

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
Re: Titanium Windscreen Design on 11/24/2013 18:06:10 MST Print View

A thread by Delmar O'Donnell prompted me to bump this thread up because it has a lot of content that relates to information gathered in his thread. In this thread we can see how shared information improves on a design. The progression of designs has led to the use of louvers to swirl the incoming air to keep the flames centralized and turbulent. As they rise the turbulence is maintained by the ridges in a flat bottomed Foster's can. A photo and video of that windscreen can be seen in Delmar's thread.

In this thread you will see the use of crenelation pot support/air entry system.

Can a plain cylindrical windscreen be the pot support?

DY
Adventures In Stove Making

Edited by zelph on 11/24/2013 18:15:19 MST.

Delmar O'Donnell
(Bolster)

Locale: Between Jacinto & Gorgonio
Thanks on 11/24/2013 20:38:13 MST Print View

Thanks for the bump, Dan. I had not seen this excellent thread.

Paul French
(SSGHawk) - F - MLife

Locale: Northern Texas
New (?) idea and best practices on 07/02/2014 21:28:30 MDT Print View

This is dedicated to Dan Zelph who provides constant encouragement, support and guidance always like a perfect gentlemen.
This is based on the concept that the longer we can keep turbulated exhaust in the space been the windscreen and the pot, the greater the heat extraction.


I call this the JenBar Swirl after my daughter and also my wife. I was young man (not baby sitting as he started beating me at chess at age 3)sitting my 7 year old super jock grandson. I watch him side down the tightly wound McDonald's playland slide and had the lite bulb turn on moment. How don't I make the exhaust swirl around the pot without too much weight addition and with the strength to stay attach permanently to the pot. I am on generation 4 or so and this week I hope to make a real prototype. I have made a number of test beds using wood stove gasket with a coat hanger to make and hold the slide swirls in the proper shape and position and the size/shape of the swirling bends. This gave me the easy ability to test the amount of swirls and the distance between the pot and the wind screen.

A probably will make the first proto type with aluminum flashing. Ultimately will use much lighter tooling foil or titanium. Not being an engineer, I had to cut up a boat load of empty cereal boxes to figure out the template to cut the slide and support tabs. Everything on that is set except for the blood the will be required during the cutting.

The aluminum flashing slide will be high temp epoxied to the pot itself(a Zelph 32 oz flat bottom ridged conquistador)The inner windscreen will be horizontally corrugated for strength since the final version will be very light Next comes a 1/16 to 1/4" of carbon felt or fiberglass insulation (insulation suggestions appreciated) and then a final corrugated tooling foil cover. The windscreen will be as tall as the stove plus clearance plus the file pot height. The temporary packing storage container will be a oatmeal round cardboard container or an old aluminum coffee pot.(packing storage containers appreciated.)

The windscreen may have a permanent bottom for rigidity and possibly swing out feet with holes to use with small stakes.

the width between the inner windscreen and the pot will be approximately 3/4" away from the pot and possibly more depending on many sides I add. Slides mean the exhaust must bend which chokes efficiency so the opening gap must me larger.

THe air inlet holes will be substantial but will be side opening as shown in Zelph's swirling inlets posted here or on his website. A drop of epoxy will help help the side hinged doors from being moved. There will be an inner lower ring of Dan's old style corrugate windscreen that will be somewhat taller than the inlet air holes & this will be epoxied in place. There will be a lip on the bottom of the windscreen that will hold a tooling foil with similar air holes as in the windscreen that can close up or limit the amount of the air inlet flow. The stove is Dan's giant starlyte that cones with his conquistador kit. I will extend the lighting wick so it can reach to an easy place to light. I am considering making the lower portion of the windstand a separate section that the top windscreen will stack onto. The stove will been epoxied to a piece of carbon felt and than to the bottom of the pot. I will have a simmer ring to fit on the top of the Starlyte as well as the ability to turn down the air inlet vents. There will be a base reflector made out of kitchen aluminum to help keep the stove cool.I may want to put a viewing pot so I can monitor the flame.

This is wear I am. Picture will follow if I get it together, up and running.

All suggestions greatly appreciated,

And thanks again to Dan the man.
Paul French

Dan Yeruski
(zelph) - MLife

Locale: www.bplite.com
The JenBar Swirl on 07/05/2014 19:08:07 MDT Print View

Hey Paul, we look forward to the completion of your JenBar Swirl. That's quite a project you've taken on. Get it up and running.....the sooner, the better :-) with lots of photos, flames and water boiling :-)))))