Gravity feed burner on a offset shaped cooking chamber

[PetesMeat]

A bit more work today, the steel for the firebox arrived so I tacked that up. Im going to cut the holes for the chute and the door after its all tacked into one piece.

Next is to put the door frame on, mount the door and then get the hole cut for the chute. Not going to fix the chute in until the firebox is on the chamber so i can see what height it needs to be at.

[Big T]

Nice!!

[Squiggle]

[ajfoxy]

Looking good. I think the end product will be a fantastic unit.

[PetesMeat]

Got a few hour hours in today, and burnt up a few more grinder disks cutting out the opening for the firebox.


Using a bit of wood clamped to the metal to guide the cutting disk for the first few passes. This helps get a straight line, and I find after the disk has cut half a mm or so, you can remove the wood and the disk will follow the groove fairly easily.

I marked all four cuts first before welding the plate in. It was easier to mark them before the plate is welded as you get clear access to the straight edge to measure from.




With the door cut out. Obviously the disk has to over shoot the stop mark slightly so there are little crosses in each corner.


With the corners welded and ground over.


Opening for charcoal chute is now marked, but I cannot be bothered to cut it out today as Im already covered in iron filings and dirt, so will do it maybe tomorrow evening. I wish I had a plasma cutter.


Charcoal chute and firebox are eager to become one. This photo should give you an idea of size, this thing is ENORMOUS! Maybe biggest gravity feed ever made?

Pete.

[Big T]

That thing is going to be a monster!!

[Squiggle]

[ajfoxy]

It is definitly in the huge category. I can't wait to see it all come together. And yes, a plasma cutter does make the job a tad easier.

[PetesMeat]

The burner is huge but the cooking chamber isn't THAT big. Im just making the burner a lot bigger than it probably should be because its a relatively unknown thing to put a gravity feed on an uninsulated horizontal chamber. Hopefully the burner will barely even break a sweat, and run more or less at idle the entire time, in which case I can shorten the length of the chute. Maybe the current chute will store enough charcoal for an entire week long burn or something...?! I can dream.

[temurf]

... its a relatively unknown thing to put a gravity feed on an uninsulated horizontal chamber.

I am very interested in how this turns out Pete. It is looking great so far.

[PetesMeat]

Done a bit more over the last few days. Remember when I said I wished I had a plasma cutter, turns out sometimes dreams do come true, and now I have a plasma cutter. First thing I did with it is cut the opening in the top of the firebox for the chute, but i had the pressure set wrong and the cut is pretty rough and messy, but after some adjustment, its cutting very cleanly.

Also got a rather exciting development regarding the air intake valves, photos below.



Plasma cutter is an R-Tech, British made, same people that make all my welding stuff. Its tiny and can cut up to 12mm cleanly.


Clamping a bit of angle iron to the edge of the door to follow with the torch to trim it down, it was a bit too long.


Firebox door hinges tacked, they are lift off so the door can be removed.


Door open and all firebox seams fully welded. Notice the rough messy cut on the opening on the top of the firebox from my inexperienced plasma torch use.


I couldn't resist trying the chute in the firebox, so I stuck some bricks in there to stand it on and tried it to see how it looked.


This is where the firebox will meet the chamber. Im still annoyed about the stainless warping making the grate all wonky like that. They look like a row of wonky teeth.


Through the firebox door


And for scale. Could this be the biggest gravity feed ever made?






Ive been needing some way of regulating air intake. I am hoping this smoker will be sealed well enough so that you can close off the air intakes and the fire will go out. Because of this, a sliding shutter type air intake was not really the way I wanted to go.

I wanted to use some ball valves but the pit calcs suggested I needed two 50mm/2inch intakes, which is just not that easy with ball valves. A guy at the gym said he would look in his stores at work and see what he can find and look what he gave me today! Two massive 2 inch gate valves:

Im going to mount one on each side of the firebox so the wheels point back. I am going to machine a tuffnol high temp composite material washer to go between the firebox and the valves, to prevent too much heat being transferred to the expensive valves.


The gate in the valves is rubber, which is worrying so I will need to keep an eye on them. The valve is rated to take liquid up to 120c, and with the tuffnol insulating fitting, hopefully the valve wont get too hot. If it does get too hot and it melts the gate, I can disassemble the valve and lasercut a metal gate to replace the rubber one.


With the valve in rough position, there will be one on either side so the hand wheels are symetrical. The tank is blue, and will stay blue, so the valves will suit nicely.


I think very fine control of the fire should be fairly easy using those valves.

I also cut out the lid for the chute but have not welded the rim on yet.

Probably won't get much more done on it for a week or so as im off to hollywood next week for work, but will be back on it when i come home.

Pete.

[Big T]

When you finally get a plasma cutter it makes you wonder how you ever got by without it. Nice looking valves

[Squiggle]

[ajfoxy]

When you stand next to it it is not so big. Looked a lot bigger when on its own. I reckon it's not much bigger than a Double Pan chute/firebox etc.
But still looks pretty interesting. Can't wait to see how it performs at the end of the day.