Hybrid reverse flow/direct heat design from 275 gallon oil tank

[tyronethompson]

Hi,

I have finally decided to make this happen, I have had a 275 gallon oil tank in my yard and I have finally got the oil out so its time to get it ready to smoke. My apologies up front because I am an engineer and overthink everything (which is why I have had this tank for over a decade) so please bear with me.

I have been looking at reverse flow designs and as I look at the oil tank and my limited budget I came across this:

on youtube where he did a santa maria style fire box on the right half on the inside with everything fully open and pulls the heat across the meat with the stack on the left. I like the idea of not having to make and attach a separate firebox so here is what I would like to do.

My idea is to put a baffle plate across the bottom make a firebox in the lower part of the tank to one side and do a reverse flow. Since I am taking away part of the cooking space to do the firebox the numbers roughly work according to Feldon's Calculator, but I still have some questions about making this work.

1. If I end the firebox where the oil tank sides begin to straighten (about 13-14 inches) is that height too low for the firebox?

2. Can the firebox opening continue right into the reverse flow or do I need a specific baffle or something to end firebox?

Above is a picture of what I am thinking about doing. The right is where the firebox is the reverse flow plate is the lighter color and the red are expanded metal cooking grates. In a later post I will get to the reasoning for the firebox opening to the side, essentially I am looking to do some direct cooking on this as well just using the right side and closing off the rest.

Any thoughts are appreciated. Thanks.

 

[cajun dozer]

did you build it?

 

[tyronethompson]

did you build it?

Got started and then life pressed me in other directions. I retired in July and the heat was a little too much so I only got started cutting. I have it taped up and laid out and I did cut the top for the stacks. I will post pictures this week. I need to get a welder then I will be doing more. Thanks for asking.

 

[tyronethompson]

Ok, its happening and I am looking for some advice. Just so you know I am an engineer not a welder, millwright, metalworker or anyone with any skill whatsoever so any comments about poor grinding or welding will be deleted, LOL! (Actually posting pictures later as Google is acting up)

That said I have the side door cut and the pictures show the inside. As you can see I my OCD got the best of me as I was attacking the rust with the grinder and I ground of one side way too early and the rust has come back with a vengeance.

My question is what is the best order to attack the tasks listed below to finish up. I have scraped out the oil sludge and as you can see the top is open and there is a hole in the far end for draining. Here is the list, please list any additional steps and if any of them need to be repeated (e.g. power wash):

1. Power wash
2. Burn out
3. Remove rust
4. Cut doors
5. Season (I have some beef tallow I was thinking about using)

Your reasoning would be greatly appreciated as well. I'm on my way to pick up some wood for the burn out and hopefully drop off the 1/4" plate I picked up to be cut on the plasma cutter at my former school. Thanks.

 

[seenred]

Hello, Tyrone.

I don't see your pics. It might help to see what you're working with in giving you answers/advice that actually helps.

As far as your plan, it seems sound to me...but without seeing your actual progress, it's hard to know.

Edit: I see now that you said you'd post pics later.

When you get the chance to post your pics, I'll definitely take a look and offer any advice that comes to mind.

This seems like a cool and unique design...looking forward to seeing it develop.

Red

 

[tyronethompson]

The last shows the door cut in the side and here is the whole tank. From my first design I switch sides because I wanted to use the drain hole of the tank rather than leave it under the firebox. The door cutouts are outlined in tape and the firebox is the upper left in the first picture which I could not get to rotate.

I don't know if I fully explained my design, it is a reverse flow with a moveable plate to allow for direct cooking similar to the example shown in my first post. But I also plan to stand the plate up to close off the grill and just use the end where the firebox is for direct cooking (if you are familiar with the Chud Box that is what inspired that idea). The plate will have a rounded end for that purpose.

 

[tyronethompson]

Hello, Tyrone.

I don't see your pics. It might help to see what you're working with in giving you answers/advice that actually helps.

As far as your plan, it seems sound to me...but without seeing your actual progress, it's hard to know.

Edit: I see now that you said you'd post pics later.

When you get the chance to post your pics, I'll definitely take a look and offer any advice that comes to mind.

This seems like a cool and unique design...looking forward to seeing it develop.

Red

I added them now. Thanks.

 

[seenred]

The last shows the door cut in the side and here is the whole tank. From my first design I switch sides because I wanted to use the drain hole of the tank rather than leave it under the firebox. The door cutouts are outlined in tape and the firebox is the upper left in the first picture which I could not get to rotate.

I don't know if I fully explained my design, it is a reverse flow with a moveable plate to allow for direct cooking similar to the example shown in my first post. But I also plan to stand the plate up to close off the grill and just use the end where the firebox is for direct cooking (if you are familiar with the Chud Box that is what inspired that idea). The plate will have a rounded end for that purpose.

Evening Tyrone,

Sorry I didn't get back sooner. Your design is intriguing, and I'm very interested in watching how this build goes. From off the top of my head, I'd say you're on the right track...but I have no experience with this type of design. I like the idea of a movable/convertible baffle plate. Should allow for more versatility. I can tell you that I built a Chud-style direct heat smoker earlier this year that turned out very nice and cooks like a charm.

If this cooker works as designed, it ought to be about a versatile as anything out there - low n slow smoking, direct heat cooking, and high-heat searing all in one unit.

I'll be following along on this one!

Red

 

[tyronethompson]

First burn out with pallet wood went for about 3 hours. Got it over 700 at bottom and all of the grill up to 500 using ir thermometer, but I am wondering if I need to do another for longer. I did pick up a big piece of oak so I can go longer. I hit it with a wirewheel cup and the oil smell is definitely gone.

I also have the 1/4" plate I picked up (4' X 4' for $80 on Marketplace!) and the upper grill grate 5' X 2' ($10 on Marketplace!). I do need to remove the handles for it to fit and I am wondering if someone has any idea how to detach them and maintain the integrity of the grate.

Thanks.

 

[seenred]

Morning Tyrone.

So far so good! Those are good finds off marketplace. A 1/4" plate, 4x4, at my steel yard currently goes for about $125.

If it was me, I'd probably just take an angle grinder with a cutoff wheel, and zip those handles off flush with the frame of the grate. Then you could take a flap disc or stone wheel and grind the burrs smooth.

Red

 

[tyronethompson]

Morning Tyrone.

So far so good! Those are good finds off marketplace. A 1/4" plate, 4x4, at my steel yard currently goes for about $125.

If it was me, I'd probably just take an angle grinder with a cutoff wheel, and zip those handles off flush with the frame of the grate. Then you could take a flap disc or stone wheel and grind the burrs smooth.

Red

Thanks, that's what I'm thinking as well.