Featured New Oklahoma Joe Highland - Reverse Conversion, Input needed

[civilsmoker]

Project is now continuing as the weather is good again for a few days.

A quick Q on your diagram. 4.75" would be the total height of the opening then? (where it says 4.5" currently) I'm not sure how to calculate the RF plate width at 4.75" is this diameter also on your diagram somewhere.
Last Q for now, how big should the gap between the end of the RF in the CC (with the lip) be, to let the heat rise? I had in mind 30", with the CC being 35" would give me a 5" gap. Thanks.

The inside opening should be 4.5 I added .25 for steel thickness. For the pate width, just measure up the end of the CC 4.75 and then measure across the CC and minus the steel thickness (2x) of the CC (it should be about 15.125 - 15.25 or so). Calcs are good for the plan then need to be adjusted in Fab (this isn't a high precision tool....) For the CC opening 4.5 to 5 inches at the end will be fine. You just want a little bigger (say 30% or so) opening than the FB to CC opening.

PS...A 1" high RF Plate dam is nice.....Oh and this is just me but I wouldn't have an issue welding the plate in with the dims you have, just don't put a hard 90 in the smoke stack that will cause an issue with flow. cut an oval hole (on the radius) or add a plenum on the flat next to the FB.

 

[civilsmoker]

Sliding shelves upper and lower are simple. just weld in angle in with a tipping bracket as below.... Very simple and effective.

Just for reference the copper pot dia is 18" so a second shelf should work for you with your CC at 17.7 dia.

 

[PhilHum]

So I spent some time today with my buddy who will be helping with the fabrication. Looking at what we'd need to do to the FB to get it the way i'd like it, we figure it's probably better/easier to just fab a new one, a rectangular one with end door. So i'm going to have some more flexibility too, in terms of optimal dimensions/volume.

I guess usually these are the same width, or slightly smaller than the CC (due to it sitting below the mid point (existing is 17.7" CC diameter & 17" FB diameter), then I guess length and depth similar to get the right volume.
So I fed these into the calculator, and it gave me the following:

On the new box i'll go for top and bottom air intakes, probably similar to these:

 

[civilsmoker]

I would make your FB taller to allow for a sliding coal pan and ash pan in the bottom and still maintain your calculated volume for burning. So I would recommend making it 17 or 18 inches in height. The other trick on the air gates is I just a 1/2 angle and then weld buttons on the slab so it slides smother and easier to fab. I post a pic later. Also double check your 1/2 moon area from the FB to CC vs the football shape. This could change the location of your RF plate. Not a bad thing you just need to follow the changes full circle.

My co-worker sent me this pic this morning from his "holiday".....

 

[PhilHum]

Thanks, yeah i'll recheck the FB/CC area. Good call on the ash tray, great idea.
Hope I can figure it out on the calculator.

Also tell your co-worker, he's got great taste. That photo was taken up in Wengen, we spent a week up there too this summer.
This is the valley, near the Jungfraujoch inspired Tolkien. The three Mountains of Moria are named after the three mountains there.

This is a pic from the place we rented.

 

[PhilHum]

Struggling a little on the FB/CC half-moon (OK it's past midnight here, so that could be a factor).
Do you think, when you've got a second, you could post an update of that great pic, you sent a few days back? Thanks.

 

[civilsmoker]

Struggling a little on the FB/CC half-moon (OK it's past midnight here, so that could be a factor).
Do you think, when you've got a second, you could post an update of that great pic, you sent a few days back? Thanks.

View attachment 509522

I’ll draw it up in the morning for you!

 

[civilsmoker]

This is how I do my vent plates now. Simple, clean, and they don’t bind up.

Ash & coal pan

I will finish the drawing tomorrow for ya.

 

[golfpro2301]

P PhilHum be careful on weight with new FB. That was my original plan but took easy way out and insulated original. By adding insulation, outer shell, and 1/4” thick door the cooker almost tips over from FB being to heavy. I barely have to lift handle for it to move. You will need counter weight of some sort under drain. I use a plate of 1/2” steel and works well. You can stack wood,bricks, etc there

 

[PhilHum]

P PhilHum be careful on weight with new FB. That was my original plan but took easy way out and insulated original. By adding insulation, outer shell, and 1/4” thick door the cooker almost tips over from FB being to heavy. I barely have to lift handle for it to move. You will need counter weight of some sort under drain. I use a plate of 1/2” steel and works well. You can stack wood,bricks, etc there

Thanks, yeah I had thought about that. Like the old Porsche 911s....the pendulums :-)

Potentially thinking of moving the FB side legs out, or adding some other reinforcement there to make it a bit more balanced from a footing perspective.
To balance the weight out though I could add another plate on the CC left side, where the chimney is now, it's got to be patched anyway because of the hole. That could be a solution. Plus I guess the RF plate will add some additional weight to the CC.

 

[civilsmoker]

So here is a sketch of the fire box with 1/2 moon.

I also ran the calc through the tutorial equations.

For the fire box area, I only use the volume above the coal pan for the calculation. I also ran the calc for the FB to CC opening. for a patio smoker this should be 20% to 30% bigger. The 30% is 44.7 sq inches. Just for reference the copper pot is a 30 gal tank, yours is about 37 gal. I used a 4.5 inch 1/2 moon. So in a nut shell the dimensions above match the copper pot design except the fire box is just a bit bigger (1.25 inches taller). If you use these dimensions I can confidently say it will work VERY well!

On the weight, you can move the legs or take a 20 inch section of the 4 inch exhaust pipe, fill it with sand and cap the ends for a counter wt..... this is what lang does on their little deluxe smoker.

 

[PhilHum]

Thanks so much for this, it's really appreciated! Also the elegant solution to the weight balancing question.
I already went on a recon run today to spec the chimney, 80 and 120mm so far, but i'll find a 4" (100mm).

As I mentioned it's unfortunately pretty difficult to buy steel sheets around here of the right thickness, but we've got some contacts, so that will be organised.
It also makes it a little easier as we're not rolling steel anymore, with the rectangular FB.

Will post pics as we proceed. This has been a huge help till now, thanks again!

 

[civilsmoker]

Oh just food for thought.....since you have a cut out from the old opening on the fire box side. Rather than plate over that, just make that opening larger and make it the hole for a plenum for the chimney. That will also make it look clean.

 

[PhilHum]

So I took another look at the FB calcs, this is what I have based on the volume above the ash tray

Length at 17" equals the diameter of the CC, height is 15 1/4 plus ashtray (18" total) depth of 14", which gives 3601" cubic.
I think this is right, according to your diagram and calcs above.

 

[civilsmoker]

You should be golden with that! Oh and if you can’t find 4 inch round you can always use 4” square. The square has more area but that is needed to account for losses. The copper pot initial plan was square, but I came across a discount 4inch round. Looking forward to seeing your creation!

 

[JLeonard]

I'm not much help on the smoker mods. But I will tell ya......I absolutely love the view from your garden!
Jim

 

[PhilHum]

You should be golden with that! Oh and if you can’t find 4 inch round you can always use 4” square. The square has more area but that is needed to account for losses. The copper pot initial plan was square, but I came across a discount 4inch round. Looking forward to seeing your creation!

Thanks so much, so now we can begin properly!

 

[PhilHum]

I'm not much help on the smoker mods. But I will tell ya......I absolutely love the view from your garden!
Jim

It's what they call a half-mountainous region here, local Alps are literally down the road. Now is actually the nicest time of year (we're getting summer at last).
Plus now, my garden has grass again in the meantime

 

[JLeonard]

P PhilHum Man that is beautiful.
Jim

 

[Brokenhandle]

Beautiful for sure! I'd love to set up our house for the last week in your backyard! Would be hard to leave!

Ryan