Introduction: Meet Meatbot: How to Rebuild a Used Smoker and Make Killer Pork BBQ
First Prize in the
Weekend Projects Contest
The next few pages will show my restoration of my barn sale $5 smoker, which we dubbed MEATBOT, and the first smoked pork we made inside of it.
Step 1: Clean!
The BBQ was cleaned with my powerwasher to prep it for new paint. I lightly rubbed the smoker down with 00 steel wool when it dried to prep the surface. The handles were rotten and removed. Upon inspection the metal looks pretty clean and unrusted, and all the parts are in good cosmetic condition other than some of the paint being baked off.
Step 2: First & Second Coat
I have a love for orange and copper colors, so I went with a tough 650 degree engine block paint. The brand is VHT and they have some really great color varieties. I did two coats to get good coverage. The color is burnt metallic copper and was about $8 a can at autoparts store. I used 1.5 cans for 2 coats. A little excessive but I wanted a good cover coat. If I had to do all over again I'd use 2 - $3 cans of Krylon BBQ black as a base coat and use the more expensive VHT as a top coat/detail paint, but this was a lesson learned in the process. :)
I decided the orange looked a little much so I added some flat black racing stripes. I placed one on either side for the handle regions on the main kettle body, and then added a third stripe down the front by the door. I masked the door off and left it orange and painted the handle flat black. I like little details, the door looks sharp.
The legs were removed and painted black. All I needed to do to the legs was hit them with a wire brush to remove some rust and scale, then washed them. The legs were rubbed with steel wool and hit with Krylon BBQ flat black ($3 can). The legs will be reverse installed to the kettle body (the first of several 'cheap ass mods'). This modification is called the firebowl mod, it will allow me to lift the smoker directly off the fire & water bowls while smoking to add more fuel. It is a very simple modification that makes the smoker more useful.
Step 4: New Handles
Some repurposed scrap dowels cut into three 4" handles. I drilled the dowels through on a drill press. I took 1/4" threaded rod and cut pieces to slide through the middle using 2 acorn nuts and 2 large fender washers to secure it. I might paint the handles at a later time, but for now I wanted to get them fitted. When it was all done I was really pleased with how the handles looked.
Step 5: Thermometer Calibrated and Reinstalled
I removed the thermometer from the kettle lid with a rubber mallet, since the stock thermometer is only pressed into place. I then put the stock thermometer into a 225 degree oven and let it come up to that temperature. After it was fully heated, I used a 1/2" ratchet on the back nut to re-adjust it to read 225 (it read 300) and marked it with a sharpie (thank you /r/smoking for the tip) Took me three tries to get it set perfectly, but it seems to work ok now. [Big Update Edit: thermometer breaks in first 10m of the cook].
I was recommended to buy a wireless digital probe thermometer (Maverick ET732) and plan to when I can scrape up $60.
MORE TO COME! (dampers, smokestack, firebowl legs)
Mucho thanks to the FrankenBrinkmann website and /r/smoking for inspiration and great information!
Step 6: Fire Bowl Legs
This mod was described on the Home Depot reviews section of the smoker and was a very easy way to add legs to the firebowl.
I used (4) 5.5" carriage bolts as legs, they cost about $2 each at Home Depot. I used a phillips screwdriver and a hammer to make pilot holes for the drill and was surprised that the screwdriver easily punctured through the metal like it was butter. I drilled the holes on an angle inside the lower bend of the firebowl using a 1/2" bit on my drill press. Stainless steel nuts and lock washers were used on the inside of the bowl where it will face the fire. Zinc coated nut used on the outside of the bowl. I will probably spray paint the carriage bolts and nuts with 2 coats of flat BBQ black to be on the safe side since i hear zinc can offgas when heated.
It sits at the perfect level now inside the smoker, and I can lift the smoker off cleanly from the firebowl when I need to dump ash, add charcoal, wood or refill the water bowl that rests on top.
The legs sit neatly under the smoker. No more bricks to place the firebowl on! I was thinking about adding handles to the firebowl, but all I am going to add is a damper to control air flow. I own kevlar welding gloves, so I can easily lift and dump the firebowl as needed.
Step 7: Installing Top Vent
So after looking at a lot of ideas for vents I decided to go with a large 1.5" hole on the top of the dome and make a single flap control to cover it. I plan to add a second (possibly smaller) vent about 3/4" in size if this one proves to be inadequate. I'd like to find a small smokestack to install at a later time.
I also painfully learned carbon steel hole saws are not really suited for working on metal. Rather than incur the expense of $40 for a set of bi-metal hole saws for one single cut, I endured and did the slow and steady method. It took about an hour, and a lot of oil, but I got through the lid.
The vent lids:
I cut the vent lids from 18 ga aluminum with my tin snips. I left a flap of metal in my cutout to bend upwards as the handle. I also rounded the edges with a bench grinder and 1/2 round file, and I sanded the metal in one direction to add a nice finish. I secured it with a small SS bolt and a leftover acorn nut to pretty it up. I had to hand bend the lids a bit to accommodate the rounded dome.
Step 8: Bottom Vents
I drilled 5 - 5/16" holes around the single 3/4" round airhole already on the firebowl. The additional airholes will help to improve air flow and increase our fire management. I added a similar vent flap seen on the lid made from 18 ga aluminum.
I started to think about the bottom vent and realized it's going to be damn hot under that firebowl while cooking. I added a piece of 3" long scrap dowel as a cheap handle to the new vent cover. I hit the wood with 2 coats of BBQ black to keep it from burning up.
I then painted the leg black where the handle sits closest to when full open. The way it is set up, the vent always closes to the left this way, and the painted leg marks full open, I sort of lucked out that it happened that way. Painting the leg black as a reference helped a lot during cooking.
Step 9: Air Management Pt. 2 - Vent Cap/ash
I had a small SS bowl in my scrap pile I used to use to hold juice/water on my Weber set up. I decided to repurpose this bowl for a vent lid to keep ash away from the bottom vents during cooking. I drilled 4 rows of holes with my drill press. Neat didn't matter for this project, airflow did. It took a bit to drill all these holes. I also filed them down so there were no sharp edges.
I placed this drilled bowl (vent cap) open side down over the charcoal bowl's vent holes so the ash will stay out of the vent area, and fresh air will be drawn inside in all directions at the same time around the charcoal for better fire management. The large water dish will rest directly on top of this vent cap, which is a nice added bonus that helped keep the water boiling steadily during the cooking process by lifting it off the charcoal.
Step 10: 9 Lb Boston Butt (BB)
First, the whole BB was rubbed with brown mustard, and a dry rub to will be applied over it. The roast weighs between 9-10 lbs. At an hour a pound we can plan to have this cooking for a minimum of 8 and maximum of about 11 hours.
Step 11: The Rub
This is my basic sugar based rub recipe. I was out of brown sugar but we had an abundance of white on hand, so I improvised. White sugar wound up working very well.
Basic Rub Recipe:
1 c sugar
1/4 c salt
1 Tbsp Adobo
1 Tbsp smoked paprika
1 Tbsp sweet paprika
1 Tbsp dry mustard
1 Tbsp italian herb blend
2 Tbsp Chili powder
1 Tbsp cocoa/chipotle pepper mix
1 Tbsp of dried minced garlic
and a few other odd and ends from the spice cabinet.
Most of the spices we use in our rubs are sourced from penzey's. - they have amazing stuff. They are also local for us in the KC Metro area. Check them out, they do mail order, the 4-8oz bags of spices are your best bargain from them.
Step 12: Smoker Ready to Go
I have everything ready to go, it's time to cap it off. The first boston butt smoke in Meatbot starts!
I can tell within the first 5m that the next mod I'll be doing after this smoke session will be sealing the inside of the lid where it mates with the body of the smoker. They sell a fireproof gasket kit for about $20. Other than this, the smoker is working as it should.
Step 13: The First Casualty - Stock Thermometer
The recalibrated brinkmann thermometer failed miserably. I took periodic temperature readings from the top vent with an instant read probe thermometer we had on hand. It ready 225-240 out of the vent fairly consistently. If the smoker got too hot I closed the bottom vent down halfway. The top and bottom vent controls worked very well.
Step 14: First Firebowl Change Out, a Look at the Meat
After 3 hours we needed to change the coals and add more wood. We can see the meat has a very nice color developing. I took the vent off, dumped the firebowl into the charcoal chimney and shook out the ash, and dumped it back in with some fresh hickory lumps. Then back to the smoke, adding charcoal and hickory wood every 90m or so.
The biggest issue you encounter with this sort of smoker is the need to constantly add water to the bowl from a boiling kettle. I added about 4 boiling kettles (about 3gal) to the water bowl over the course of a 7-8 hour cook. Luckily you can easily access the waterbowl from the front door, and if you are careful water can be added to the bowl from here.
Step 15: Meat at 5 Hours, 6 Hours
5 hours into smoke. Then 6 hours in. Note color change. We did a second firebowl change at 6 hours.
Step 16: Texas Crutch, Igloo Treatment.
The cooking temperature stalled after 7 hours at 155 degrees, so I did the texas crutch. I wrapped the BB in 2 layers of heavy duty foil, added 1/2 a cup of apple cider vinegar and sealed the pork BB up. I removed the water bowl from the smoker, and added 15 fresh briquettes. I sealed the smoker up with vents on full open for the next 90m and let convection finish the cooking.
The BB was pulled from smoker reading an internal temperature of 198. We tossed the foil wrapped BB in a small Igloo cooler for an hour to rest. The Igloo treatment can now begin, which will finish off any cooking and bring the juices back evenly into the entire BB.
Step 17: Voila! Meatbot Delivers.
10 hours of smoky goodness at work here. Smoke ring 1/2" deep. The keel bone wiggled a bit and pulled out cleanly. Overall my family and I were really happy with Meatbot and the BBQ it produced. Thanks for reading my first Instructables listing.
Any questions? firstname.lastname@example.org // re:Meatbot check me out on Tumblr: http://docsteamcrunk.tumblr.com
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