Make a Frontier Stove From a Gas Bottle

I recently saw a frontier stove online and thought how awesome it'd be for camping.

I also thought the cost was silly and that I could make one just as good for next to nothing.



Materials Needed:
- an EMPTY 15kg gas bottle - Free from a co worker
- 3mm or thicker sheet steel - Quite rusty but free from a friend
- 15mm box section - Again, a bit rusty but free from another friend
- 60mm steel pipe (5x 500mm lengths) for the chimney
- 30mm steel pipe (about 2m)  for legs
- Some scrap bits of plate to make the leg brackets
- metal hinges - had laying around the garage
- Heat resistant stove paint - eBay
- A carrying handle with screws - eBay
- A smaller handle for the front hatch - eBay
- 6mm steel rod - for leg pivots
- 4mm split pins (cotter pins) x 3
- m6 nuts
- m6 threaded rod or 60mm m6 bolts
- 3 right angled brackets
- metal mesh (for the spark arrestor)

Tools needed:
 - Angle grinder with both cutting discs and flap discs.
 - A welder (I used a MIG but an arc welder would work just as well)
 - A paint pen or marker.
 - Drill with 6mm bit, 10mm bit and also a wire brush attachment for removing rust.
 - Jigsaw with metal cutting blade
 - Sandpaper. I used wet & dry sanding sponges.
 - Screwdrivers. Normally used for levering.
 - A wire brush. Handy for cleaning up welds.

Step 1: Drain the Gas Bottle

I can't stress how important it is to do this stage safely. The gas bottle must be completely devoid of combustible gas.
If you don't do this stage properly... well... gas + air + angle grinder = hospital/morgue

Even if the bottle is empty, it'll still have residual gas inside which must be purged.

There are various methods for emptying bottles and removing the valve. Have a look on the net, you'll find methods involving using spanners and scaffolding poles to unscrew the valve. Lump hammers to smash it off. Or, as I did, make a hole and fill it with water.

Lots of suggestions here.

http://www.mig-welding.co.uk/forum/showthread.php?t=9210

For mine, the bottle was empty to start with. Nevertheless, I first used a screwdriver to wedge the valve open. I left it in the garden for a few hours to be sure.

I then very slowly drilled a hole through the brass valve on the top of the bottle. 

The bottle was then filled with water. I drilled a bigger hole in the top. Emptied the bottle and then left it upside down to completely drain. 

I then forgot about the project of a couple of months.

Step 2: Cut the Top Off the Cylinder

Using the chalk pen, I did my best to mark an accurate circle round the top of the gas cylinder.

Carefully lop the top off the cylinder with the angle grinder.

I found it easiest to lay the bottle on it's side against a wall. Brace it with your foot. Use the angle grinder at a right angle to the bottle.

Step 3: Cut the Base Off the Cylinder

Then tidy up the bottom of the cylinder by cutting off the...err... not sure what it's called...  the round bit in the picture.

Step 4: Cut the Side Off the Cylinder

Now we want to flatten off the cylinder. 

Draw another line with the paint pen about two thirds the way across the cylinder.

Again, lop this bit off with the angle grinder.

Step 5: Tidy Up Edges

Swap out the cutting disc on the angle grinder for a flap disc.

Grind off any protruding left over bits from the base of the cylinder and also go round the sharp edges left over from cutting.

Step 6: Cut Stove Top and End Plate.

Using the already cut drum section, draw round it on your steel plate.

Add about 10mm round the edge to provide a lip and cut out with your angle grinder. Clean up the edges a little with a flap disc.

Now do the same with the opening at the end of the cylinder (So you're making a 'D' shape about 20-25cm across)

Step 7: Cleanup. (Kind of Ironic As My Garage Is Now Mostly Blue)

In order to paint the stove, I needed to strip all the blue paint off the cylinder.

I used the angle grinder again with the flap disc. It worked, and didn't take that long. However, everything in my garage (including my motorbike) is covered in a fine layer of blue dust.

In retrospect, I should have done this outside.

I also took this opportunity to use a wire brush attachment on my drill to remove all the loose rust  from inside the cylinder.

Step 8: Make a Door!

Draw a 150mm circle on the end plate.

Drill a 10mm hole (probably best to drill a smaller pilot hole first)

Weld a hinge onto the plate and if necessary, tidy up the welds with the angle grinder. You should be able to position the hinge to hide the 10mm hole you drilled earlier.

I also welded a small triangle of steel onto the back of the door frame to prevent it swinging inside the stove.

Step 9: Weld Front Plate to Barrel

Put the cylinder on it's end (You might need to clamp it down as the base is of course it's rounded.)

If you put the end plate in place, you should be able to see if it fits properly. It may be necessary to grind the lip of the cylinder a little to make it properly flat.

Make a few holding welds to brace the plate, then run a weld around the seam.

For belt and braces weldy goodness, run a weld around the inside of the seam too.

As you can see from the pictures... my welding skills suck. However, the angle grinder comes to the rescue once more and it should be possible to grind excess weld down so it's nice and smooth.

Step 10: Drilling Holes and Brace the Top Plate With Box Section.

Drill 60mm hole near back of top plate for the flue. I chose to put it right in the middle.

Cut a section of 60mm diameter tube about 100mm long and fit it to the hole with about 30mm protruding.

You really want to make absolutely sure this is straight. Otherwise, you'll have a wonky chimney.

The best way I found was to put some wooden blocks down on the bench and place the top plate down on them with the tube hanging down and actually resting on the work bench. That way it should be at a near perfect right angle to the bench and so should the top plate.

Run a weld around the tube.

Flip the top plate over and weld it from the other side too.

Weld box section to re-enforce the plate right along the middle (make sure you're doing this on the underside!)

Step 11: Sexy Legs!

For this bit you need the tubes you've selected for the stove's legs. Some metal plate (I used 2mm). Some 6mm bolts about 40mm long and a lump of wood (ideally, about 2mm wider than the tube you're using.

The tubes that I'm using for the legs are 30mm in diameter.

Cut out six plates of plate steel in a sort of fat L shape (see picture). 

Pair them up and if possible. Each pair is used to make a bracket for one leg.
Grind the plates so that they fit the curve of the barrel.

Take your first pair of plates and using a lump of leftover wood (which in my case fortunately happened to be a rather perfect 32mm wide) and clamp the steel either side of the wood.

Front leg
Place this assembly on top of the barrel at the door end and used a L square to ensure it is pointing straight up (it helps to be as accurate as is sensible with this bit)

Then I welded the plates to the barrel. Be aware that the wood will probably burn whilst doing this.

A plate was welded to the very end for added strength and to help prevent the legs from folding too far.

Drill a 6mm pivot hole through both plates ensuring that the inserted tube will have enough clearance to pivot.
Drill a corresponding hole in the tube. You should be able to put a 40mm bolt through the holes to check that the leg will fold properly (Don't tighten anything up yet)

Now you can mark out and drill 5mm holes so you can put a locking pin through the leg in both the closed and folded position. Check the alignment with a 4mm split pin.

Rear legs
The whole process was repeated twice more at the other end but with the legs shifted about 100mm either side of centre.

Step 12: More Leg Work.

Step 13: Cut a Door in the Top

At the last minute, I decided that I'd put a trap door in the top of the stove to allow fuelling without opening the main hatch.

In retrospect, there was a lot of mucking around in this stage as the door wouldn't originally open with the hinge I used. It meant leaving a gap at one end.

I marked things out (making sure to be clear of the brace in the underside of the plate), then using the angle grinder with a cutting disc I chopped a 6in square into the top.

The underside was braced with box section and overlapped by about 5mm. 

I wrapped a hinge around one edge (that was flush with the opening rather than 5mm overlapping. 

The plate that was removed was cut short by about 10mm then welded in place (making sure that it'd properly open)

I ended up welding a small plate underneath to protect the hinge and stop smoke coming out of the gap.

I also drilled a 20mm hole in the top of the plate. A short section of spare tubing was welded underneath and capped off. This means that we can hook the flap open from above but it won't allow smoke out. (See pictures)

Step 14: Add a Carrying Handle.

I added a carrying handle.

I got a fairly sturdy but cheap handle off of ebay.

Blow-torched and sanded the ends to remove paint.

Drilled four holes for screws. The screws were welded inside and then the heads were welded outside. (This might be overkill)

The ends of the handle were welded to the barrel. 

A wire brush was used frequently to remove peeling paint.

DON'T MAKE THE SAME MISTAKE I DID. Ensure you attach the handle on the same side as the top hatch hinge. 
I managed to attach it on the opposite side... so the to hatch flips open when carrying the stove. I had to weld an identical handle onto the other side in the end.

Step 15: Attach a Handle to the Front Hatch.

I got hold of a small handle and welded it to the front hatch. 

Unfortunately, at this stage I had run out of gas so tried welding with gasless wire. NEVER AGAIN! The stuff is horrible!

Step 16: Paint the Inside of the Barrel

This step isn't entirely necessary... but I wanted to do this for neatness.

Clean up the inside (make sure the majority of rust is gone) and it's free from grease, moisture or dust.

Spray the inside of the barrel with heat resistant paint.

Leave it for 20 mins to dry and give it a second coat.

Do the same for the underside of the top plate. Be sure to mask off the edges where it will weld to the barrel.

Step 17: Weld Top Plate to Barrel

It turns out that I had a big problem with warping. 

The top plate was quite badly heat warped during the welding of the bracing and trap door. 

I tried various methods to solve this. From liberal hammer application, to clamping. These lessened the warping; certainly enough to weld things in place.

The top plate was put in place. I found I had about 10mm gap around the lip in places.

The whole thing was inverted and using beams of wood and clamps; I managed to pull it down enough to close the gap.

I then went around the entire edge and placed small spot welds at 80mm intervals. I then released the clamps and welded the seam in sections so as to minimalise any further warping.

Step 18: Chimney Pipe

The individual chimney sections need to be short enough to fit inside the stove for storage. Cut each section to about 70mm shorter than the available space inside the stove (You want to be able to store them inside when not in use)

The sections need to slot together. To do this, we make a smaller connecting section.

Cut a 100mm lenght of the 60mm tube and cut a 10mm strip out of it (see photo)... You may need to adjust this amount depending on the thickness of the walls.

Work this connecting tube in a vice to close up the gap. Do so in increments at different rotations of the tube (to maintain the circular shape)

Fit the connector into the chimney segment. It should fit down about 50mm. You may need to gently clamp it to get it to fit.

Clamp the exposed end of the tube slightly to hold them together and reduce the circumference slightly. Run a weld down the line.
File the weld flat and sand off the tube so that it'll fit into one of the other 60mm sections.
Run another weld around the join between the connector tube and the chimney section.

File off any bits of weld that will prevent the pipe from fitting into the exhaust on the stove. Make sure it fits.

Now go and make several more sections. You're aiming to raise the chimney as high as possible but only making enough sections that you can store inside the stove when it's not being used.

Step 19: Chimney Damper

Take one of the chimney sections and drill a hole through it about a quarter of the way down (so it's clear of where the connecting sections are)

Now cut a circle of plate steel a bit smaller than the circumference of the chimney.

Weld two nuts to it (See pic) making sure that they are in line with each other.

Take a length of 6mm threaded rod and use it to fit the damper disc inside the tube.

Weld the nuts to the threaded rod (this will need you to weld inside the chimney, might be a bit tight)

Bend the two ends of the threaded rod at right angles (bend them in line with the disc inside the chimney). Make sure you bend them in different directions.

I messed mine up a bit and had to balance it out with a few spare nuts. But it seems to work fine.
I also made the disc slightly too large so it sticks a bit. Next time I'd make it at least 4mm smaller than the inner diameter of the chimney.

Step 20: Paint It

You're going to need a couple of cans of stove paint. This stuff should withstand the high temperatures that the stove will be putting out.

Normally, you need to use heat resistant paint in temperatures above 10 degrees (Celsius) so if, like me, you're making this in a cold climate you will need to heat your working area. 

It's also a good idea to put the can in a bowl of warm (tap hot, not kettle hot!) water to heat up the paint itself.

The next bit is simple. Just spray it over the whole stove. Make sure you get it into the seams and open up the top flap to make sure you get it all round the opening. 
Do the same for the chimney sections and leave everything to dry.

Step 21: Spark Arrestor

As an additional step, I decided to make a spark arrestor to sit on top of the chimney.

This should stop sparks escaping and damaging any surrounding tents or other flammable items.

It's also a brilliant opportunity to attach some lashing points so that the chimney can be tied down to prevent it blowing over.

I came up with a design very close to the ones used commercially.

I took another tube section (about 250mm long) and cut two holes either side leaving a 15mm wide section to support things.
Some mesh was bent into shape and welded in place (this was an absolute pig to weld. Probably only about 50% of the welds worked, the others just melted away the mesh. But it's enough to hold everything in place)
A bit of left over plate was rounded off and welded to cap off the tube.
A connecting section (same as the normal chimney sections) was welded in place. The spark arrestor will now happily sit on top of the chimney and hopefully prevent sparks getting out.

I also got hold of three right angled brackets and attached them around the circumference to allow it to be lashed down. I'll probably use half a dozen split rings to make a short chain to attach ropes to (rather than tie the ropes to the potentially hot steel)

Finally it was all painted and left to dry.

Step 22: Epilogue

So I now have a shiny (Ok, black) frontier stove.

Parts wise, it worked out a lot cheaper than buying a stove new. However do bear in mind that I scrounged most of the bits.

Effort wise, It's been a couple of months since I started the project and I've been working on it every so often. So I guess in man hours, it'd be cheaper to buy one... but not nearly as satisfying.
Plus I know that this one is built like a Chieftain tank... and definitely isn't going to break or bend.

I look forward to testing it out when camping this March :)


UPDATE 03/04/2013 : The stove was tested last weekend (30th March) and it worked well providing the wood was dry. Temperatures on the camp site were bitterly cold (allegedly -10C one night although I don't fully believe this) and there was also a problem with all of the wood available on site being unseasoned and frozen. We ended up using whatever we could get hold of in the stove (wood, charcole and coal).

There was also quite a problem with soot. I needed to remove the butterfly valve chimney section and the spark arrestor as they were so badly clogged. The chimney itself had to be occasionally removed and the soot knocked out of it.

All in all , it was a life saver at keeping a large 20 litre tea urn filled with hot water for cooking, washing up and hot water bottles.