Firstly I had taken an old gas bbq and stripped off the old & rusted gas fittings, rebated an internal edge and added support bars under the shelf.
I worked out the components required then set about making them from an old battered fireplace box, chimney & flu.
The outer insulation box -
The main fire burn chamber & heat riser -
The original drip tray with large cut out for the heat riser -
All the bits. *Notice also a piece of 100mm box pipe, this will be the wood feed shoot -
Position the insulation box through rebates in frame and lower onto bottom shelf -
Lower the main burn chamber / heat riser through the top of the outer insulation box, aligning with the pre cut positioning slots in the base.
I have also cut two small holes through the bottom for ash drainage -
I have also cut two small holes through the bottom for ash drainage -
Continue assembly with tapping the wood feed shoot through front and into the main burn chamber then adding the drip tray and bbq plates -
Finish it off and christen it with half a milk create of fine twigs, great food & good friends -
Umm... did I mention, some Fine Food -
.... and some good friends !
After dinner we removed the bbq plates then enjoyed an open fire.
Additional info I posted on http://www.aquaponicshq.com/forums/forum.php *IMO the #1 Source of quality info !
ReplyDelete-----
As with a Rocket Mass Heaters the main utilization of heat is based on the hot gases produced and not the flames.
After a 5 min warm up the Rocket BBQ required only a small amount of attention to keep a nice cooking temp.
A laser thermometer was used to find that the internal base of the burn chamber was hovering around 500C and the cooking plate 200C. With the bbq plates removed and the hood lowered a testing temp of 380C was seen on the hoods inbuilt thermometer, thus creating more than usable oven temp's.
As stated in so much of the available online references, we found that small twigs & branches of less than 15mm diameter produced the best combination of heat production & burn time duration. The create of larger diameter branches (15-30mm) in pic above was not used for cooking.