Milo Stove: making some small parts

This is post #5 of the Milo Stove project. Post #4 is here:

https://bkhome.org/news/202308/milo-stove-drilling-the-lid.html

I am using the Speedster burner, but intending to make my own. So have purchased five of these little 30ml aluminium cans (from eBay):

The burner will have to sit right on top of a bolt-head, so I indented the underneath like this:

...used some aluminium tube, then hammered it, to get this indent:

The rotating disk underneath the burner, that will throttle the air-flow, will have a little handle outside of the Milo tin, so as to control the throttling. I am using a small screw and part of a spade terminal. The plastic insulation on spade terminals withstands high temperatures. The screw is small enough so as to be able to forcefully screw into the end of the spade terminal (where wire is normally inserted):

The mesh stand that I previously constructed, on which the pot will sit, will probably not be in the final stove. Instead, there will be a grill of some kind, mounted onto the sides of the Milo tin. I used the ring-pull tops of baked-beans tins to create these mounting brackets:

Used a 25mm chassis hole-punch to cut a very neat hole in the chicken-tin:

Did a preliminary burn test, and the flame was not coming out through the hole, so used pliers to widen the hole. The result is not neat, but the flame came out very nicely, perhaps a bit too much:

The Packafeather stove has a 27mm - 27.5mm diameter hole, so perhaps that is the magic size.

The metal is a bit brittle; could not work it out wider, it tended to break. So might purchase a slightly bigger hole-cutter. Or maybe try a stone grinding wheel to widen the hole a little bit. So, looks like back to Coles tomorrow, to purchase another chicken-spread tin.

As mentioned, will probably not use the wire-mesh pot-stand shown in the above photo. The grid on which the pot sits could be the fan-grill as shown in post #1, or could use stainless steel skewers. Bought these from Coles:

Have other things to do for the next couple of days, but will get back to this project soon.     

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Milo Stove: drilling the lid

This is post #4 of the Milo Stove project. Post #3 is here:

https://bkhome.org/news/202308/milo-stove-chicken-tin-and-mesh-stand.html

The lid of the Milo tin is being re-purposed as the base on which will sit the alcohol burner. As mentioned in post #3, the air inlet is underneath the chicken-tin. Here are the holes drilled in the lid:

The air-inlet holes are nominally 9mm diameter, though I was a bit cautious and they are actually more like 8mm.

Cutting 8-9mm holes in thin tin is tricky with a hand tool, so I first drilled 2mm, then 5mm, then reamed it out and a final touchup with a round file. My reamer is a hand tool; they are readily available, look like this:

After drilling all the holes, here is what the 30ml Speedster burner looks like when placed on the lid:

The chicken-tin goes over that, held in place by pieces of aluminium rod riveted on three sides:

...have not yet drilled the 25mm hole in the top of the chicken-tin.

The construction plan was created in SolveSpace. Here it is exported to PNG:

As the diagram shows, there will be a circular piece of aluminium underneath the Milo-lid, that can be rotated to adjust air intake.

As you might glean from looking at the diagram, the Milo lid is about 12mm above the bottom of the tin, with 8mm holes right around the bottom-side of the Milo tin. Note also, the Milo tin is being used upside-down.

Of course, this design is an experiment and it will be great if it performs well, but not guaranteed. If anyone thinks that this idea for throttling air intake is patentable, I state right now that the Milo Stove design is public domain. I don't see anything patentable about it; however, patent law in some countries, particularly the USA, is so broken that even the most trivial innovation can be patented.   

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Milo Stove: chicken tin and mesh stand

I thought maybe call this "Barry's Milo Stove", but just "Milo Stove" is enough; named after the Milo tin.

This is post #3 of the Milo alcohol stove project. Previous post:

https://bkhome.org/news/202308/milo-tin-for-alcohol-stove-project.html

The stove will be built on the same principle as the Packafeather stove, with burner inside, covered with a tin that has a hole in the top for the flames to come out. Here is the Packafeather XL stove:

I looked through the shelves at Coles for a suitable tin to go over the Speedster burner, and found this:

This is Podravka Chicken Spread, made in Croatia. Outer diameter at the widest is 75mm and height is 32mm, which is a bit smaller than I was looking for; however, the next size up was fish tins, that are a bit too big. It's OK, the chicken tin will work.

After removing the ring-pull lid (and cleaning it out), there is a ridge all around the inside, where the ring-pull lid was attached:

The Milo Stove will have air flowing in from underneath, and due to the rather small diameter, needed to get rid of that ridge. A small grinding wheel worked. The electric drill was clamped onto the bench, and it was easy to grind the ridge down:

...still to be done, a 25mm hole in the top of the chicken-tin.

I also constructed a mesh stand, on which the pot will sit. Bought this from Bunnings:

https://www.bunnings.com.au/rapidmesh-600-x-900-x-1-1mm-25-x-12-5-silver-wire-mesh-panel_p0203642

The idea is that when everything is packed into the stove, the TOAKS pot will be inserted inside the Milo tin, and the mesh stand can be either inside or outside the pot.

Cut out a piece of mesh, 25 segments, each segment is 12.7mm:

Here it is wrapped into a circle. Circumference is 318mm, diameter 101mm, height 56mm. There are hooks to hold it together:

...the stand looks OK, but not necessarily the final design. Also, will be considering the alternative method, of a round grill mounted on the sides of the Milo tin, as shown in post #1 of this stove project.   

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Milo tin for alcohol stove project

Continuing the alcohol stove project:

https://bkhome.org/news/202308/experiments-with-an-alcohol-stove.html

Well well, I found a tin exactly the right size, at the local Coles supermarket. It is 700g "Milo Pro":

I used to drink Milo as a child. Have transferred it into a jar, now looks like will have to get into drinking it again. As a hot drink in the evening will be nice.

The Milo tin dimensions are perfect. The tin is slightly higher than the aluminium construction, but that is exactly what I want. Serendipitous!

Have drawn up the plans for the construction, using SolveSpace. This will be a complete DIY alcohol stove with simmer adjustment. Had to order a few bits and pieces off eBay, so will be about a week away before can commence the build.

Those Speedster alcohol burners can easily be constructed, so also have ordered some ceramic wool, fine stainless steel mesh and 30ml aluminium cans. There are YouTube videos that show how to do it:

https://www.youtube.com/watch?v=GZ3mzbskhCE

https://www.youtube.com/watch?v=LK1gifdLPoA

https://www.youtube.com/watch?v=en_iQ_vbRn4

Here is the Speedster 30ml burner:

Up until recently, I went along with the established doctrine that these simple burners are the least efficient, despite my own tests showing otherwise. Then I saw this video, that finally has thrown out the false information about efficiency:

https://www.youtube.com/watch?v=-GFCofvFVM0

...testing an X-Boil burner, which is same principle as the Speedster. The simplest burner is great!    

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Experiments with an alcohol stove

Several days ago, I posted some thoughts about alcohol stove design:

https://bkhome.org/news/202308/some-thoughts-about-alcohol-stove-design.html

So, considered testing with the combined Speedster burner and Packafeather adjustable stove. Also, I wondered how close the windshield could be to the pot and still draw the fumes upward ok.

So, I constructed an aluminium windshield tube, with brackets inside to hold a grill, on which the pot will sit. The gap between pot and innner-side of windhield is only 5mm (using my TOAKS 1000ml titanium pot). The aluminium sheet is 0.5mm thick. Photo shows the constructed windshield/pot-stand, alongside the Packafeather stove:

That grill is actually a fan grill. They have welded joins and will withstand considerable heat -- in fact, while testing it was glowing red hot and held together. I bought it from here, the "120mm" size, which is actually 115 wide by 115mm high:

https://www.aliexpress.com/item/1005005572335210.html

With 500ml in the pot and the Packafeather vents wide open, it burned very hot. Here is a snapshot with the lights out:

From the post several days ago, I had the idea of combining the Packafeather with the Speedster, so set that up. Started with 500ml water -- a US cup is 238ml, so a bit more water than many tests on YouTube where they use two US cups for a boil test. No lid on the pot.

Winter here, cool evening. Didn't measure the temperature, but estimate ambient and water to be about 15 degrees C. With the Packafeather vent wide open, boiling was starting to happen after 10 minutes, became vigorous at 12 minutes.

At that point, I wound the Packafeather vents down to fully closed, and the flame became small. This is what we want for true cooking, to leave on simmer, so that the beans, seeds, legumes, or whatever, have fully cooked. Then waited until the flame went out...

The Speedster burner is "30ml" and at the start I put as much in until it was full. Didn't measure, but it would have been about 30ml. After a short time, turned the vent to be very slightly opened, then waited...

The flame went out after 48 minutes and 45 seconds!

Wow, that is a long simmer. That was yesterday. Today investigated the other idea from the post several days ago, of placing an aluminium doughnut-ring over the Packafeather stove. Also, instead of the grill, decided to use the Packafeather mesh stand:

Still using the Speedster burner, again filled to the brim. This time, it caught me by surprise. I looked at the pot after 8 minutes and 48 seconds, and hey, it was already boiling -- very vigorously. I don't know when it started boiling.

I immediately turned the Packafeather vent to closed. A couple of minutes later, the flame went out and I checked, all of the fuel was gone.

The lesson here is that the Speedster was getting too hot, boiling the alcohol too fast. Yes, got a very fast boil, but not so good for simmering.

Interesting, it is a balancing act. We don't want the burner, that is, whatever is holding the alcohol, to get too hot. Nor to cold -- which is why those who go camping in alpine areas carry some foil to put under the burner, as insulation from the ground.

This is all "fuel" for further thought. It would be nice to publish a DIY design that has adjustment like the Packafeather -- but doesn't require an actual Packafeather, given that they are no longer available.

And, I wonder if there is a tin can about that size. The aluminium tube that I constructed is 130mm outside diameter, 125mm high. Will go hunting the shelves at the local supermarkets.   

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Some thoughts about alcohol stove design

I posted recently about planning a new windshield and stand for my titanium pot:

https://bkhome.org/news/202307/idea-for-a-stove-windshield-and-stand.html

There are two little stoves that I own and love. The Speedster stove:

https://bkhome.org/news/202109/helena-campsite-and-speedster-stove-test.html

And the Packafeather XL stove:

https://bkhome.org/news/201606/packafeather-xl-stove.html

...you can see, it is just a cup into which alcohol is poured, and an outer part goes over it to control the airflow. The great thing about this is it can be adjusted down to simmer, which allows to cook food, not just bring it to the boil.

Zen Stoves is a wonderful site for those interested in the design of alcohol stoves. This page explains that the simplest type, like the Speedster stove, is slightly less efficient that one with an outer air control like the Packafeather . That's the "Open Flame Alcohol Stoves" and "Chimney Alcohol Stoves":

https://zenstoves.net/Stoves.htm

The greatest advantage of the Speedster stove is that it is spill-proof. The fuel can be left in it and the lid screwed on. Even with fuel in it and the lid off, it can be turned upside-down and no fuel comes out.

Why can't the two, Speedster and Packafeather, be used together? Replace the cup into which alcohol is poured, with the Speedster. Yes, I tested it and it works great. The flame is controllable right down to a simmer.

So, have decided to go for that combination. Then, watching some YouTube videos, came upon what this guy did with his Packafeather stove:

https://www.youtube.com/watch?v=NsTD-V6R3QY

He created an aluminium foil ring, that fits on top of the stove, then the windshield is placed around it:

Note, his Packafeather stove is a different model than mine, different brackets on which to place the pot. The little brown part is the handle for a cap used to extinguish the flame. The foil ring placed on the stove:

...that is very interesting. He is restricting the airflow that comes in through the windshield holes, so that most will go via the holes in the Packafeather. I'm going to try that!

Unfortunately, Packafeather stoves are no longer manufactured. It was a one-person cottage industry. It's a shame when innovative little products like that just disappear. It's the same with websites; my blog for example has years of informative posts, but after I die or go gaga, the domain name will expire and that's the end of it. Anyway, that's the way it is, time marches on.   

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Idea for a stove windshield and stand

For many years have hiked with my great little titanium 1 litre cooking pot. However, to cook a hearty meal at end of a day of hiking, would prefer a slightly bigger size. So, have ordered a 1.3 litre pot. It is TOAKS brand, same as before, same height at 100mm, just a slightly bigger diameter:

Ordered it from here:

https://www.aliexpress.com/item/32854649082.html

Then had some thoughts about the stove. My favourite stove is from Speedster Backpacking Products (SBP). Fantastic little stove. Purchased in 2021 and posted about it here:

https://bkhome.org/news/202109/helena-campsite-and-speedster-stove-test.html

To digress, over the years I have tested many ultra-light camping stoves. It was a thing with me, would see something new and had to test it. Here are some posts:

https://bkhome.org/news/202106/ultralight-wood-burning-stove-for-hiking.html

https://bkhome.org/news/202107/testing-mk1-tent-and-wood-stove.html

https://bkhome.org/news/201606/packafeather-xl-stove.html

https://www.bkhome.org/news/201606/vargo-triad-stove.html

Back onto the SBP stove, it is great, but the tiny stand not so good:

Granted, it is very light, great for backpackers. However, I found it to be a bit tricky with a heavy pot on top, especially if the stand is sitting on soft ground.

Sometime hopefully not to far into the future I plan to tour with my recumbent trike, so extreme light weight is not so important. Want to keep that SBP stove, it is great, but can re-think the stand and windshield...

I'm planning to use a cheap aluminium camping pot as the windbreak and stand.

The plan is to drill a row of holes around the base of the aluminium pot, where the air gets drawn in. And remove the handles and dump the lid. The SBP stove will sit inside on the floor of the pot, and there there will be some brackets 45mm above the floor of the pot, on which the TOAKS pot can sit. Thus, the TOAKS stove will be nestled in the aluminium pot and there will be a chimney effect. The wind-shield and chimney-effect are key to the SBP stove working well.

This proposed design would be very stable, the main point of the exercise.

I have edited this post, removed some proposed details, as a bit premature. There are various ways this can be implemented, so better to do a later post with details after it is actually done.   

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What kind of people ride recumbent trikes?

Interesting question. We see these slim athletic lycra-attired riders zipping along on their racing bikes.  Do recumbent trikes attract a different sort of person?

I wanted to find out if there are any cycling groups in Australia specifically for recumbent riders, and discovered yes, in Adelaide, Brisbane and Perth. The Adelaide group looks most active; I watched a video of one of their outings:

https://www.youtube.com/watch?v=G5jQAI-qKzs

...they are not slim lycra-clad athletes!

Quoting from here:

https://laidbackcycles.com/blogs/news/who-are-recumbent-trikes-good-for

Recumbent trikes are designed for comfort. They make cycling a more relaxing activity, while also preventing pain in the back, shoulders, and wrists. Many people find they can cycle greater distances because their body is so relaxed. Because the seat is ergonomically correct, recumbent trikes keep your head in a natural, erect position. You enjoy greater visibility, a bonus when touring new areas or taking in the beauty of nature on cycling trails. Facing forward also means you are more aware of your surroundings so you are less likely to have accidents. You can sit back and enjoy a comfortable ride.

There was only one guy in that outing who had a two-wheeler recumbent, shown in the above photo -- looks dangerous. I notice a lot of them are electric-assist.  

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