Help figuring out what's wrong - won't burn all the fuel


 
I'm going to make a fuel basket for my smoker. I think it'll help with raising the temperature and helping with a complete fuel burn.

Thinking of something like this:

IMG_20160909_102129.jpg


The idea is that above my air inlet in the smoker, will be the basket. It'll have a solid-sided metal strip 'stand' that it sits on in order to keep the airflow contained under the fuel. The bottom of the actual fuel basket will be mesh, as will the sides. This will allow the air to flow through the fuel. I'll put a solid plate on top of the basket to divert the heat out the sides of the basket for indirect heating in the smoker. This top plate will be removable.

Anyone see any problems with this? Suggestions for improvements?
 
Looks good to me, seems like you'd be able to get one hell of a fire running through that. Not sure the solid top plate is necessary though
 
I'm really late to the thread, but you smoker is just like an UDS, so I would study up on them, a bit and see what in general work with them and what not.

I have used a weber charcoal grate and then I wrapped expanded metal around it to create a basket. I can hold around 20 pounds of charcoal and could smoke at around 220°f for about 40 hours on a single full load. About the maximum I could get would be around 400°, as others have said ceramic can hold the heat much much better then metal.

Some people put a diffuser plate in their UDS, to get a more even temperature, but I have not had the need for one. Also, im not sure if you posted earlier in the thread, but make sure you reading your temp in the center of the grate about a inch or so. I use a clip, that attaches to the grill. UDS can vary from +-40 or more from the center to the edge or from grill to the exhaust area.

Also, you want the grill height about 24 inches from the bottom of the basket, as a general rule. Not to close that food will burn and not to far away that you have to burn more coals to get a certain temperature..


Well I have thrown my .02 cents in and all might be a little late, to this thread, lol.
 
I did put together a basket. it's about 18" in diameter and the sides are about 7" high - maybe too big.
Please don't laugh at my lack of welding skills.

IMG_20160909_180851.jpg
 
Looks good but I would have left the bottom open as well. When ash start to pile up on the coals and around your intake, it may cause problems. Also, since the coal you lite will be on the top of unlike coals you will probably have issues after long cookstory when the ash starts to build up.
 
I saw a UDS basket with an 'air channel' directing the air under the coals and thought that would be a good idea for my smoker also. I wanted the air to be directed up into the coals and not be able to get around them on the outside.
I can get a circular area of about 20" diameter about 2" deep before it plugs up the air inlet. I'll clean it out well before it gets that deep.
Going to the store to get something to cook on it tomorrow. Will post a link after it starts.
 
heating up the smoker now.
http://heat-makarios.ddns.net/

And now the pork shoulder is on...

The BGE exhaust vent daisy wheel is all the way open and the entire top is slid open about 1/8-1/4" open in addition to that.

I have PID settings at 6, .01, 4 which is think is the default. Is that where I should be?

I apologize if the HM web page is slow or sometimes doesn't work. I have my garage door closed now and it blocks the WiFi from working very well out there.
 
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I tried to choke off the exhaust a little bit to see if the temp would settle at 240. I couldnt' get it so I set the temp at 225, which is really where I wanted it anyway.
It's running pretty nice at 225F now.
I'm running with the Micro-Damper on it and the BGE exhaust daisy wheel open fully, with the large opening part completely closed.
So far, it doesn't seem to be running much different than when I did all the testing before, even with more fuel and the charcoal basket.
 
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I strongly believe you were bypassing too much air around your charcoal and too little air was used for combustion in your previous design. That is why your temperature bloomed when the blower stopped. I had the exact same behavior with my UDS. I solved my problem exactly as you did and now I can easily hit 500F or run for 20 hours with 10lbs of charcoal at 225F.

I would suggest you drill a bunch of holes in the steel plate on top of your charcoal basket so the heat and smoke can go straight up as well as out the sides.

Here is my charcoal basket and air duct:

Revised%20Charcoal%20Bin.jpg



Air%20Duct.jpg


The air blows in from the side of the drum, through the high tech air duct and then under the charcoal basket.

Here is a pork shoulder I started this evening and the PID parameters I have played with tonight:

HeaterMeter%202016-09-10.jpg


I have my damper set to full open at 30% and the blower does not begin to blow until 40% with a maximum fan speed of 50% and a startup max of 75%. It is a 6.5cfm blower from Auber Instruments.
 
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The initial lid open was me turning it on, knowing that the temp always goes way high at first.
Then after the grate was heated up, I opened it to clean the grate. Then closed it and went in to get the meat and put it on about 12:33pm.
A little unorganized at first today.
It's settled down nicely though. There were some larger fluctuations at first. Does this mean my PID settings are incorrect?
 
To be honest, I'd bump your fan max down a bit. Not now, just let it run the course to see how it behaves.
 
I did just now change the max fan to 80%

I'm assuming that the P is the % in the PID settings, right? Wait, no... P means Proportional.
What would I change on the PID settings? I'm currently at:
P: 6
I: .02
D: 4

My smoker is a 64 gal well pressure tank.
I am using the micro-damper right now.
 
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Try lowering P to 5 or 4.5. I may be thinking backwards, but that oscillation I've had before, and it worked.
Looks like it's still running within 5 degrees either way of the set point, which is much better than you could probably do without the HM.
 
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OK. P is now at 4.5.
I have to take the ribs off in 30 minutes, then slather with sauce and put back on for another 30-60 minutes.
 
RKHanso said:
OK. P is now at 4.5.
I have to take the ribs off in 30 minutes, then slather with sauce and put back on for another 30-60 minutes.
Click to expand...

When you open the lid to take the ribs off and slather with tasty BBQ sauce, I would suggest self invoking the "lid open" mode before opening the lid, and let the lid open run it's course after closing.
 
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