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Farmer John

"Top Hat" spins freely and closes ....

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Re: "Top Hat" spins freely and closes ....

Okay does anyone have a problem with the "top hat" spinning itself closed? I have not figured out a way to keep it from spinning so freely. Any ideas besides wedging something (ouch hot!) between the lid and it?

John

Maybe your keeping it too clean? hehe :lol: I have not had that problem.

-=Jasen=-

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I think Farmer John is trolling for Kamado owners with stuck dampers. Oh, poor me. My damper spins too freely. And my wife is too beautiful, my lawn is too green and my ribs are too tender. 8)

Perhaps, if not cooking at very high temps, some teflon tape will correct this "problem".

But on a bigger note, while the spinning cap is attractive and iconic of a range of K-style cookers, I'm starting to think that as a control it is fundamentally flawed.

I have a Mexico-epoch K7. My damper has never stuck but it seems to be a not uncommon complaint - one which KK has addressed in part through coarser threading. But for a low-n-slow on my cooker I only open the damper 1/4 turn. The K7 has a 10tpi pitch so 1/10" x .25 turn is 25/1000 inch gap. The KK is probably similar and while lacking the sticking problem is, I would guess, a tad fussier in terms of temperature change per unit of adjustment.

Also, with only a 25/1000 gap, any tip of the cap changes the gap from one side to the other. As long as nothing is touching, it might average out but when trying to make small tweaks that play might, er, come into play.

More problematic is that at certain parts of a long low-n-slow, the moisture from cooking condenses in the gap and reduces the opening. There is no drip lip so if cooking in the rain, the rainwater wicks around the bottom and further exacerbates temperature control issues. (Yes, I know a Stoker or Guru addresses this issue but I've been generally quite successful with the manual method. And using the electronic controls in the rain presents other problems.)

By recollection, the hole in the top is about 3" across. If so, the circumference is, in round numbers, 10" and the area of the opening is 0.25" or a square 0.5" on a side.

I therefore submit the following concept:

Reshape the damper cap so instead of a flat bottom it is a hood. This provides a drip lip and preserves the current look.

Place a damper similar to the one on the front of the draft door into the throat of the dome opening. Turning the top cap will rotate that plate to adjust airflow. Threads are eliminated altogether as are condensation, tilting and rain problems. The shape of the openings on the plate could be designed to provide finer adjustment at the low end of the range if desired and a small notch on the edge of the cap could provide a visual reference for remembering settings.

There are a few details of proper design of the mounting bracket for use and assembly but I think the basic concept is sound.

Thoughts?

Dennis, if you like the idea, I'd be happy to accept a cobalt blue Gen II Ultimate proof of concept prototype for testing. :)

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I think Farmer John is trolling for Kamado owners with stuck dampers. Oh, poor me. My damper spins too freely. And my wife is too beautiful, my lawn is too green and my ribs are too tender. 8)

Perhaps, if not cooking at very high temps, some teflon tape will correct this "problem".

But on a bigger note, while the spinning cap is attractive and iconic of a range of K-style cookers, I'm starting to think that as a control it is fundamentally flawed.

I have a Mexico-epoch K7. My damper has never stuck but it seems to be a not uncommon complaint - one which KK has addressed in part through coarser threading. But for a low-n-slow on my cooker I only open the damper 1/4 turn. The K7 has a 10tpi pitch so 1/10" x .25 turn is 25/1000 inch gap. The KK is probably similar and while lacking the sticking problem is, I would guess, a tad fussier in terms of temperature change per unit of adjustment.

Also, with only a 25/1000 gap, any tip of the cap changes the gap from one side to the other. As long as nothing is touching, it might average out but when trying to make small tweaks that play might, er, come into play.

More problematic is that at certain parts of a long low-n-slow, the moisture from cooking condenses in the gap and reduces the opening. There is no drip lip so if cooking in the rain, the rainwater wicks around the bottom and further exacerbates temperature control issues. (Yes, I know a Stoker or Guru addresses this issue but I've been generally quite successful with the manual method. And using the electronic controls in the rain presents other problems.)

By recollection, the hole in the top is about 3" across. If so, the circumference is, in round numbers, 10" and the area of the opening is 0.25" or a square 0.5" on a side.

I therefore submit the following concept:

Reshape the damper cap so instead of a flat bottom it is a hood. This provides a drip lip and preserves the current look.

Place a damper similar to the one on the front of the draft door into the throat of the dome opening. Turning the top cap will rotate that plate to adjust airflow. Threads are eliminated altogether as are condensation, tilting and rain problems. The shape of the openings on the plate could be designed to provide finer adjustment at the low end of the range if desired and a small notch on the edge of the cap could provide a visual reference for remembering settings.

There are a few details of proper design of the mounting bracket for use and assembly but I think the basic concept is sound.

Thoughts?

Dennis, if you like the idea, I'd be happy to accept a cobalt blue Gen II Ultimate proof of concept prototype for testing. :)

Actually, your last suggestion is one already being discussed. But I am not fond of putting more metal dampers in a high heat area (SS in a high temp cook will do some nasty stuff, especially adding that much more thin surface area). Maybe removable that can slip over the threading as an option.

The cap of the GenII KK's already has a lip and a recessed area, which I am also not as fond of; now rain is not a problem, but condensing smoke vapor dripping all over the top of the grill is. I think as large as the KK tophat is verses the dome opening, rain would be a minimal issue.

Also, when you combine the top damper with the finer adjustment knob on the bottom damper, you get a surprisingly sensitive adjustment. I questioned that myself before receiving a KK. Having had both grills, I like the course tophat thread better.

-=Jasen=-

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Having both grills on my patio, I concur that the course thread allows very fine control over the temperature for low/slow cooks. I find that the "play" in the hardware allows mine to make contact on one side before tightening and leveling off to make a full seal. That means I can have VERY fine adjustments by rotating the hat as little as an inch when doing low cooks.

FWIW, my KK is much more reliable and predictable with the temperature settings. My #5 always tried to sneak the temp up on the longer cooks, but the KK is rock steady. Must be the bottom wheel?

I am with DJ on the dial-in top. It would be a good accessory, if the whole assembly was threaded so you could screw it onto your tophat bolt when you wanted it, and take it off when you dont.

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Reshape the damper cap so instead of a flat bottom it is a hood. This provides a drip lip and preserves the current look.

I concur. I have never been happy with the spin-top control. My KK style hat is much, much better than the rusty old posK style, but I still do not like the control. I would prefer a daisy-wheel style top damper as you suggested and for which I have already seen plans.

:roll:

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...But I am not fond of putting more metal dampers in a high heat area (SS in a high temp cook will do some nasty stuff' date=' especially adding that much more thin surface area).[/quote']

What are the "nasties" to which you refer? If stainless steel is safe enough to place my food on, then surely from a safety standpoint it is OK for a damper.

As to the heat, according to the A to Z of materials (http://www.azom.com/details.asp?ArticleID=1175), "...The second most common reason stainless steels are used is for their high temperature properties; stainless steels can be found in applications where high temperature oxidation resistance is necessary, and in other applications where high temperature strength is required..."

In the A to Z table showing the intermittent and continuous maximum service temperatures of various stainless steels, the lowest number I saw anywhere was 620C (over 1,100F) which is far beyond what is necessary for cooking and several hundred degrees F beyond what typical self-cleaning ovens reach.

I don't think I'd use sheet stainless but thin plate - perhaps 3mm or so. I'm sure a bit of testing would determine the best thickness.

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...But I am not fond of putting more metal dampers in a high heat area (SS in a high temp cook will do some nasty stuff' date=' especially adding that much more thin surface area).[/quote']

What are the "nasties" to which you refer? If stainless steel is safe enough to place my food on, then surely from a safety standpoint it is OK for a damper.

As to the heat, according to the A to Z of materials (http://www.azom.com/details.asp?ArticleID=1175), "...The second most common reason stainless steels are used is for their high temperature properties; stainless steels can be found in applications where high temperature oxidation resistance is necessary, and in other applications where high temperature strength is required..."

In the A to Z table showing the intermittent and continuous maximum service temperatures of various stainless steels, the lowest number I saw anywhere was 620C (over 1,100F) which is far beyond what is necessary for cooking and several hundred degrees F beyond what typical self-cleaning ovens reach.

I don't think I'd use sheet stainless but thin plate - perhaps 3mm or so. I'm sure a bit of testing would determine the best thickness.

First off, I did not say "nasties", I said SS does some nasty stuff at high temps. What I was referring too was the fact that SS has a high coefficient of thermal expansion (I think it was around 50% more last time I looked at a chart). If the link you refer lists this information, you will see SS will be at the higher end of the chart. I weld on SS all the time and see what heat does. I can also remember my old K 1/4" grill grate getting so hot that the rod ends expanded into the sides and then caused the rods to bend during high temp cooks (which was why I made a sear grill support for the k long ago).

So again, my problem is that two flat surfaces of SS are going to give you problems if they have to mesh together to form a seal as there is going to be movement at high temps. So depending on the design, they could either bind or just not seal. I would also not insert this device into the throat of the opening as if it cannot move one way, it will move the other and that could be disaster for the neck area. I would instead have it sit on top of the opening, held in place via the existing acme threaded tophat bolt. Cast iron would also be a better choice for the device too. (This picture is looking way familiar, think Green) :wink:

Don't get me wrong, I think it is a fine idea at low temps. But I don't see the need as what I have works perfectly well. I think Majestik's situation would be improved if he could get Dennis to build him a KK style front draft door for his K, as the combo of the dial on the lower and his tophat works great.

-=Jasen=-

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What I was referring too was the fact that SS has a high coefficient of thermal expansion (I think it was around 50% more last time I looked at a chart).

So again, my problem is that two flat surfaces of SS are going to give you problems if they have to mesh together to form a seal as there is going to be movement at high temps. So depending on the design, they could either bind or just not seal.

I think Majestik's situation would be improved if he could get Dennis to build him a KK style front draft door for his K, as the combo of the dial on the lower and his tophat works great.

Gosh, how does a Weber kettle hold together? I still think the idea merits experimentation. I volunteer for beta testing.

;-)

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Gosh, how does a Weber kettle hold together? I still think the idea merits experimentation. I volunteer for beta testing.

;-)

Have not seen many weber charcoal SS grills in a similar configuration (I am sure there is one somewhere) or gas grills that can hit 1000 degrees at there damper (if they have one). Not to mention the KK is channeling all of the heat directly up that small chimney since it is insulated for low thermal loss. An all metal grill is distributing the heat over a large mass.

But hey, whatever floats your boat dude (why don't you get a KK first :shock: ). I would rather Dennis spend his time on other projects since his existing damper works perfectly well (with a KK :eek: ).

-=Jasen=-

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But hey' date=' whatever floats your boat dude (why don't you get a KK first ). [/quote']

:eek::D That was pretty harsh!

But there is some validity to the statement...You gotta try the shoes on before you can say they aren't comfortable!

I have no problem with the damper controlling temps, and am absolutely opposed to a dial in lieu of the damper. A simple dial control that threads onto the existing damper bolt is a perfect solution, offering the user both options.

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But hey' date=' whatever floats your boat dude (why don't you get a KK first ). [/quote']

:eek::D That was pretty harsh!

Nah, that is not harsh. Me smacking him down at Halo3, now that is harsh!

BTW, if I were making one, it would be cylindrical with openings on the outside walls. That way the tophat would just snug down on it.

-=Jasen=-

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Mine didn't start doing it until after several long and slows and a couple roasty toasties. I saw the behavior for the first time last night, when I'd open the top a quarter to a half turn, and it simply wouldn't stay - it would just rotate itself back down until the gasket was just touching.

I'm planning on spinning it all the way off this weekend and looking at the threads to see if I need to wash off some greasy soot.....

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