This is my attempt at making my own Tandoor Oven. I browsed a few designs and came up with this setup. Its low cost, fairly compact, lightweight and portable.

Its charcoal fuelled, with an air intake and sweep out hole at the bottom.

Step 1: What You Need...

Parts:
* Oil container drum 20l+ (free)
* 2 clay pots which fit above (£10)
* vermiculite (10 litres £4)
* 2 bricks (free)

Optional:
* broken tiles/rubble (free)
* 3 metal knobs
* sand/cement

Tool/Skills:
* Angle grinder with stone cutting disc
* Hammer
* Flat blade screwdriver or chisel
* Drill and masonry and hss bits

Step 2: Cut Open Lid of Can

I used an old blunt screwdriver which i hammered continuous holes around the top edge.

Remove cut lid. Use a hammer to flatten round the sharp edges.

Its a good idea to tape over this rough edge to prevent cuts to your hands as you will be working inside it.

Remove any remaining oil using a dry cloth.

Step 3: Cut Air Holes

Similar technique as lid to cut can air hole.

I beat a and tapered edge outwards using a ball pein hammer and a wooden stump as a beating base.

Pot already had a drain hole. I drilled 4 extra air holes around it.

Step 4: Base Pot & Handles

I fitted 2 side metal knobs i had lying around.

The bottom pot was placed on broken tiles. I also dded some sand to the tile base. Lower pot was inserted and side filled with vermiculite for insulation. I made a paper funnel to get vermiculite in through the narrow border edge. Fill it up to the rim of the pot.

Step 5: Top Pot & Lid

Pencil mark depth of lid cut. I cut using an angle grinder with a stone cutting disc and eye protection
Other people have used a hand tenon saw for the job.

Smooth off the base and lid for a level finish. I added a metal knob with washers for convenience.

Step 6: Stack It Up!

Position the top pot, with wide mouth of top pot touching the rim of lower pot.

I was running low on vermiculite so wedged in some extra broken concrete pieces to fill up the void. Its not the best of insulators but it does help hold the top half in situ.

Fill remaining edge voids with vermiculite.

Step 7: Cap It Off!

This step is optional.

I decided to cap off the vermiculite using sand cement and broken tiles.

This will prevent vermiculite from blowing away, getting wet and keep it weatherproof should it get left outside.

I added broken tiles to minimize cracking and the mosaic finish looks hip. Lets see how well it lasts.

Sponge wipe the cemented tiles for a clean crisp finish, ensuring no sharp tile edges are protruding.

Leave to dry.

Step 8: Finished Product

Loads of cooking space in there. Should be able to do 3 naans at a time or several skewered kebabs.

Its a shame the tin wasnt a bit taller for the extra insulation.

Stack it up on 3 or 4 half bricks to keep the air hole clear and leave some space for an ash collection tray.

Step 9: Lets Get Cooking!

Place coals in a firestarter. When they start glowing red, add to tandoor oven.

Leave the lid slightly open for air circulation and give it 20 mins to get up to temperature.

Wait for coals to go white hot.

I skewered some marinated chicken breast pieces on a hanging skewer and placed in oven. I left lid slightly ajar and left to cook for half hour.

For cleanup, pick out any large lumps and sweep cold ashes down the air hole into an ash collection tray. Beats cleaning a barbecue grill!

Step 10: Conclusion

Tandoori Chicken had the authentic tandoori taste. A little crispy on bottom of skewer end. Need to adjust height of my skewers.
Lamb seekh kebabs came out a treat.

Worked well even with exposed chimney.
Final verdict is waiting for thr naan bread test.

Any improvements?
Yes, add a charcoal tray to prevent charcoal lumps from blocking air intake holes. I made this from external plaster beading hammered into shape. To remove galvanizing i left it to sit on hot coal lumps (or you can use acid)

Also recommend making larger or make more surrounding satelite air intake holes.

The metal lid knob gets hot, so use a wooden one.