Diffuser question

[iRacer]

How high above my fire basket should my diffuser be given that my basket is 9 inches tall and 12 inches from the bottom of the drum to top of basket?

[Richtee]

A few inches ;{) DDave prolly has a spec, but seems I see 4-6 inches or so.

[DDave]

How high above my fire basket should my diffuser be given that my basket is 9 inches tall and 12 inches from the bottom of the drum to top of basket?

That's a great question. I wish I knew the answer.

Mine is about 15" from the bottom of the drum. But I'm not saying that's where it should be. Curious to hear where others have theirs.

I have toyed with the idea of moving it up some -- maybe about 20" or 21" from the bottom of the drum. Seems to me a little higher up would allow for more convection currents to form and wouldn't block quite so much heat. Be interested to hear Rich's or BBQ E's thoughts on this line of thinking.

Hope this helps . . . some.

Dave

On Edit: Oh sorry. You asked about how high about the fire basket. Well, you get the idea.

[Richtee]

oops- I din't read the question... I meant from the top of the basket. Doh.

I'm not gonna question Dave on this, and I'll also bolster the convection thing. You want the diffuser above the heat enough to allow free flow of the heated air.

One COULD prolly fashion a few rods and set them at the bottom, and adjust their length to find an optimum? Dana...someone just yelled yer name...

[DDave]

oops- I din't read the question... I meant from the top of the basket. Doh.

You answered it properly, Rich. He asked about the measurement from the top of the firebasket. I'm the one that read too fast and answered from the bottom of the drum.

I'll also bolster the convection thing. You want the diffuser above the heat enough to allow free flow of the heated air.

I've wondered about that but have not drilled the extra set of holes to evaluate it yet.

Dave

[iRacer]

You answered it properly, Rich. He asked about the measurement from the top of the firebasket. I'm the one that read too fast and answered from the bottom of the drum.

Well, I would think that either dimension would work. I think I'm gonna try 6 inches above the basket and see where that gets me...unless I hear otherwise.

Thanks guys

[DDave]

I think I'm gonna try 6 inches above the basket and see where that gets me.

Let us know what you think.

What kind of diffuser are you using?

Dave

[iRacer]

At the moment I'm using a disposable round grill topper layin on top of my basket. I've got a piece of steel cut up the same size round as my grill grates but I'm unsure of the hole sizes I should use. I asked some guy awhile back about hole size and spacing, but he never got back to me.

I've got to make a trip to the restaurant store this week to pick up some jerky racks and I think I just may pick up a 18" pizza pan and run the uni-bit around it for now. I got the whole week off so I gonna experiment a bit. I've got a bunch of those adjustable shelf brackets, gonna burn em off tomorrow and slap em in the drum.

[Smokin' Dick]

My charcoal basket is 12" tall and stands on 3" long bolts for legs. I put the diffusers, yep, two of them, right on top of the basket. Each plate is 1/4" thick steel and the openings are different on each so the diffusion can be adjusted. Works great and that 1/2" of steel down there is a GREAT heat sink. I know nothing about heat dispersion, air flow, convection, conduction, infiltration, etc. What I do know is the drum got me a 5th place in ribs at a comp last weekend. Try the plate sitting right on the basket, if that doesn't work for you add some brackets and put it at a different height. Me? I'm kinda lazy and find the easy way to be the right way!

[DDave]

I asked some guy awhile back about hole size and spacing, but he never got back to me.

I hope it wasn't me.

I did use a pizza pan with some extra holes in it awhile back. Couldn't tell you what the spacing is though.



But I'm using these made my SmokeMeister now.

Try the plate sitting right on the basket, if that doesn't work for you add some brackets and put it at a different height. Me? I'm kinda lazy and find the easy way to be the right way!

The problem I found when putting a plate right on top of the basket was that it really reduced the burn time. I could still do ribs but it was pushing it to do pork shoulders and briskets were out of the question.

With the SmokeMeister diffuser set at about 15" from the bottom of the drum and a 17" x 6" basket of charcoal, I was able to get enough burn time (18 hours+) to do a brisket and burnt ends.

http://www.smoked-meat.com/forum/showthread.php?t=17401

YMMV of course.

Dave

[iRacer]

LMAO, it was you. It was quite awhile ago. Aint gonna hold it against ya tho

[DDave]

LMAO, it was you. It was quite awhile ago. Aint gonna hold it against ya tho

Oops. Was it a PM?

(DDave checks his PM inbox and sees the PM from iRacer dated 4-29-2012. )

Sorry about that. I remember it now. I got it while I was at a conference in Sacramento and by the time I got back home I forgot about it.

I'll get you those measurements either today or tomorrow. Wife's birthday today so I don't know if I will get a chance today.

Dave

[DDave]

PM sent.

If I fail to respond to a PM in the future, feel free to send me a reminder or a swift kick or whatever it takes. That goes for all that may be reading this. I'm always happy to answer questions and don't want anyone to think I'm blowing them off.

Dave