I would like to attempt to make my own Caldera cone. From what I understand reading the marketing materials, it's just a cone-shaped wind-screen that has a slot opening for your pot handles to stick through and the circular opening at the top is just the right size for the rim of your pot to rest without falling. Are there other pieces to hold the pot in place that I am unaware of?

Can I find the metal at my local ACE or OSH hardware store? What aisle is the metal located and when the old guy working there pounces on me and asks what I'm looking for, what do I tell him?

Piper, check out 2Question's Youtube video on how to make a Caldera Cone.

http://www.youtube.com/watch?v=VerP7-aiEBw

Edited by dsouth on 03/25/2011 17:11:09 MDT.

It is a good quality aluminum alloy. You might find aluminum flashing (roofing and siding materials) in a hardware store, which is typically softer stuff. Aluminum comes in many alloys and varies in hardness, flexibility, etc. I have re-purposed some aluminum duct material with decent results.

The Caldera cone is a very precise cut. The coupling for the side is a dovetail sort of arrangement that is a precise fit and the top is cut just right for the pot. In other words, it is harder to make than you might think. I thought it was expensive until I had one in my hands. They earn their keep!

Check out zenstoves.net for instructions and templates to make a cone-style pot stand (among others):
http://zenstoves.net/PotStands.htm#Cone

If you go to your local library you can probably find a vocational instruction book on sheet-metal bending and cutting. Have fun and watch your fingers-- the cut metal can be very sharp. You can sandpaper the finished edges to dull them or I use a knife sharpening stone to un-sharpen them.

Diane, once you get the aluminum Caldera mastered, you can move up to the titanium version.

Seriously, that would be step up, because titanium is difficult to work on. After all of that trouble, you could burn wood in it. Whereas, the aluminum one would deform from that much heat.

--B.G.--

Time to go to Ikea and get a DIY wood stove for a few dollars!

The thing about wood stoves that I just don't get is why not leave the stove home and just place your pot right on top of a tiny fire?

So "aluminum flashing" is the name of the material?

Maybe if it's really super hard to do I shouldn't try. But then again, I have learned how to make shoes so maybe I can learn how to make one of these.

Maybe you can trade your skills with shoes etc. for a cone ? Nothing like division of labor.

Dianne, it is not hard at all. I have made three. Aluminum flashing cuts easily with household scissors. If you viewed 2Questions video he simplifies the pattern making process. It is about an hour project.

Piper, you can put your pot directly on a tiny fire. However, in many areas of California in the summertime, open wood campfires are not allowed. In some areas, they classify a Caldera stove as a camp stove, not as a campfire, since it is enclosed. Open wood campfires are kind of bad if it is windy. That is the beauty of the titanium Caldera, because you can burn wood, or alcohol, or Esbit. With the aluminum Caldera that you propose, you can burn alcohol or Esbit.

If you put a sheet of aluminum underneath the Caldera, you should be able to eliminate any trace of your fire after you leave.

Get the design pattern and study that before you start.

Aluminum flashing metal comes in rolls of various widths, lengths, and thicknesses. Start with a Home Depot and work your way out.

I doubt that you will find it to be super hard. Still, there will be tricks to be learned. You will probably need a hacksaw or some tin snips, and then some other tools. Air holes are normally drilled with an electric drill.

--B.G.--

Bob,

Any tips on doing a good small "brake" ? for precise folds and bending?

"Any tips on doing a good small "brake" ?"

You know, that is one shop tool that I don't have. I've needed one several times in the past year, and I don't even know where I can borrow one.

There are some hand tools that you can purchase cheaply, and you can make a rolled edge on soft metal. That is about as far as I will go, I think.

I managed to put a rolled edge on some titanium foil. However, titanium seems to be a bit on the brittle side if you get the edge formed too sharply.

--B.G.--

I'd recommend the .003" titanium from Suluk46. I made a cone with an inferno insert for woodburning with a fosters pot. The cone is .5 oz. Complete woodburning setup (cone, internal cone, grate, and 'floor' is 1.5 oz. For closure, i just did tabs with slots and holes for tarp stakes to hold up the pot (I did two sets, one higher for woodburning and one lower for alky).

the photo's a little deceptive do to the wide angle, but the cone is slightly taller than the Fosters can.

Edited by brendans on 03/25/2011 20:39:00 MDT.

Thank you for all the info. I should have done it today. Instead I made another pair of shoes. What is the matter with me???

Maybe I can make a cone tomorrow. The only reason I want one is for my alcohol stove so that I don't even need a fancy stove that lets me set the pot on the stove, just a cup to hold the alcohol.

After seeing the Fosters can above, I wonder if I could just put a cut half of a Fosters can around my alcohol stove as a pot stand/wind screen. Punch a bunch of holes in it for ventilation. Maybe that's all I really need.

A Caldera cone is effective because it represents an almost perfect wind screen for whatever is burning inside it. The size of the holes, the quantity of holes, and the placement of holes are each kind of non-trivial.

The second thing that is effective about it is that it holds your cook pot just right.

You could produce something very easily that accomplishes some of these two points, but it probably won't be as light.

--B.G.--

Hi Piper,
I live in SB and I have an aluminum caldera cone -- if you want to come play with it for inspiration, let me know. I'm thinking of upgrading to an ULC version to fit in my pot, but I'm also toying with the idea of hacking up my aluminum cone with my utility knife... Anyway, shoot me an email at echaplin at gmail dot com if you'd like to see a cone in the flesh before you get started. Cheers, Liz.

"Bob,

Any tips on doing a good small "brake" ? for precise folds and bending?"

I'm not Bob..but...

I've made ~5 cones of varying quality before finally really getting it to look really nice (the others were functional, but I'm an engineer, form and function are both important when I have to look at it all the time). The lack of an angle brake/press brake of my own is generally the most difficult part of making one. What I've found works best is this:

Find an end table, coffee table, piece of wood/board, counter top, or other rigid thick surface with a very sharp 90 degree edge. Rounded edges won't work.

Next, find a book that is at least as tall as your edge that you're bending is long. It needs to be a hard cover book. Any other flat stiff object will work here though, a board, piece of metal, etc.

Place the edge you wish to bend over the edge of the table/countertop, overhanging the amount you wish to bend over the edge of the table/counter.

Place the book on top and roll over the edge of the table/countertop, bending the metal as you roll the book. This will get you to approx a 90 degree bend (just a shade under due to spring-back).

From here you can flip the metal over so that the newly bent edge is facing upwards. Use the book to press the surface down to make the bend 180 degrees.

Depending on how close that gets me to a 180, I'll sometimes pinch the edge down with a pair of pliers.

This is how I've finished the connecting edges (in place of the dovetails the production calderas use) on all of the cones I've made.

Hopefully those instructions make sense...using those and the youtube video on constructing a cone, you should know enough to be dangerous ;)

> http://www.youtube.com/watch?v=VerP7-aiEBw

This has a measurement error in it. When using this method to determine the radii for the conic section, use the red lines (on the sloping side), not the central black line as suggested.

Either that, or use my script for creating templates...

Edited by captain_paranoia on 03/28/2011 12:06:14 MDT.

Piper --

Take a steel rule or some flat stock, the thickness of the fold and clamp it and the stock together. I use my workmate, but you could do the same with a pair of 2x4 and C-clamps.

Extend the edge of the cone material about 3/8" beyond the flat stock.
Take a piece of hard wood and slowly work the cone material around the edge of the flat stock. The thinner the flat stock the smaller the bend radius.

I can post a picture if the description is unclear.

You should be able to produce a nice fold which will interlock.

The trick will be in placing the fold so the correct diameter is produced to hold the pot.

I leave the geometry of the cone up to you. It is all high school geometry.

Vent holes can be drilled with a spade bit if you have a very light touch. You may want to clamp the sheet between two pieces of wood.

You only need nice, sharp, precisely positioned folds if you intend to copy Trail Designs' design closely.

There are plenty of other joints that can be used that are simpler to make, simpler to mate, and just as robust and reliable. I use a simple slot and tab joint for my clones.

For instance:



Admittedly, this uses a folded reinforcement on the edge. I make this by running a fine-tipped ball-point pen along a ruler to pre-form the fold, and then complete to fold with a thumbnail, or spoon, or similar smooth tool.

Edited by captain_paranoia on 03/30/2011 06:16:05 MDT.

Kevin -- nice job. Not sure how you get at the pot handles, but just a detail.

The interlocking joint would be tough to hit. Your idea is much better. The folded edge is needed for stiffness.