Direct Fire MLT Insulation Project

[android]

well done bobby, that thing looks sweet.

 

[humann_brewing]

Well I guess it is harder than I thought to find the Aluminum I need to wrap around the keg. the big box stores only have up to 48" wide and that won't cut it Headed down to a aluminum shop in the ghetto to see if I can find what I need.

Hoping to do your build justice, wish me luck

 

[Bobby_M]

How about some aluminum roof flashing? I know it's really thin but if you do two layers and use some backing washers on the rivets, it should be fine. You could also fold that edge over so that you're going through more than one layer.

 

[humann_brewing]

How about some aluminum roof flashing? I know it's really thin but if you do two layers and use some backing washers on the rivets, it should be fine. You could also fold that edge over so that you're going through more than one layer.

Yeah, I may have to look at other options. I took the 45 minute drive to the metal foundary just to find out their power went out earlier that day and the office was closed. There were still workers there and said I could check out any scraps they had but they had just got rid of a big stack recently and really didn't have anything around that wasn't stainless and impossible to bend.

So it's either try to go back there or go to lowes down the street again. If I recall, the did have flashing that was wide enough for the height of the keg right?

 

[Bobby_M]

Lowes:
Amerimax 20" x 10' Roll Aluminum Flashing
Item #: 12540 | Model #: 66320
$8.37

If you put your zip code in to the website, they'll tell you if they carry it at your store.
That should be enough for a double up. Even with the doubling, I'd probably put a 2" fold on the end where the latches attach.

 

[humann_brewing]

Lowes:
Amerimax 20" x 10' Roll Aluminum Flashing
Item #: 12540 | Model #: 66320
$8.37

If you put your zip code in to the website, they'll tell you if they carry it at your store.
That should be enough for a double up. Even with the doubling, I'd probably put a 2" fold on the end where the latches attach.

Thanks, they didn't have it locally but didn't charge anything to ship it to me so it is on its way :rockin:

Also, I went with the small bold and nut instead of the rivets so I will use some washers on the back side.

 

[Bobby_M]

To cap this one off, I wanted to show you what the end result was.

I went low tech on sealing the top of the insulation off. I picked up a tube of light grey 100% silicone caulk. There's about a 1/8" deep trough where the skin stuck up past the insulation. I applied some masking tape on the keg at the same height as the aluminum wrap and then filled that gully in with silicon. I used a squeegee to make a nice finish by riding the aluminum edge all the way around. While it was still wet, I removed the masking tape.

A closer look at the finish. Not perfect by any means but good enough.

I used a small piece of aluminum roof flashing between the insulation and keg to cover the handle. A bead of silicone seals it from the inside.

I also put a bead of caulk down in the crevice between the keg and top skirt because grain bits always get lodged in there. It also sealed the drains. When cleaning, I found that a paper towel or sponge was needed to get water out of this place.

I also have some practical data since I brewed on this thing recently. I mashed at 155F and I noted a drop to 153 at 30 minutes, then down to 150 at 60 minutes. A 5F drop in 45F ambient with only 7 gallons of mash is a success as far as I'm concerned.

 

[sjlammer]

This is genious. i am always getting hops, wort, dust in there.

 

[Bobby_M]

I might have to do this to my BK too. I hate when a near boilover sends three streams of sticky wort down the sides of my kettle.

 

[ThePig]

This is genious. i am always getting hops, wort, dust in there.

Totally agree, that seam is a B$tch to keep crap out of.

 

[Orfy]

Looks good. What about a lid, any plans?

 

[Bobby_M]

I just have two circles of reflectix that I shove under the rolled lip on the top skirt. The diameter is large enough for a pressure fit.

 

[DBbrewing]

Nice Job Bobby I think I will do this to my system, thanks.

 

[bendavanza]

the seam on my bk always has small leaves and crap in it. it's a PITA to clean out and I end up getting soaked by the water spray I use to try to clear it.
Bobby your MLT insulation rig looks very clean. Nice work!!

 

[humann_brewing]

To cap this one off, I wanted to show you what the end result was.

I went low tech on sealing the top of the insulation off. I picked up a tube of light grey 100% silicone caulk. There's about a 1/8" deep trough where the skin stuck up past the insulation. I applied some masking tape on the keg at the same height as the aluminum wrap and then filled that gully in with silicon. I used a squeegee to make a nice finish by riding the aluminum edge all the way around. While it was still wet, I removed the masking tape.

how much silicone did it take to fill up that gap? Isn't it about 1 inch wide around the whole keg?

 

[Bobby_M]

It took less than one full tube for all of it. I know it looks like a lot on the outside edge but it's only 1/8" deep. Basically I made the outside wrap stick up a bit proud of the insulation. Then I put a huge bead down and used a squeegee to flatten it by riding it along the wrap.

 

[humann_brewing]

It took less than one full tube for all of it. I know it looks like a lot on the outside edge but it's only 1/8" deep. Basically I made the outside wrap stick up a bit proud of the insulation. Then I put a huge bead down and used a squeegee to flatten it by riding it along the wrap.

Thanks, I put it together last night, had to work with it a bit to get the fittings to stop leaking with the extra space but now to seal it.

 

[brewslut]

I can see we will have to have you back for more DIY talk!!

 

[Maltose]

anybody else do this to their kegs? those insulation numbers were pretty impressive.

 

[BucksPA]

i am going to give this a whirl in the very near future, maybe even ordering everything i need tomorrow. currently, my mlt is naked and I have always relied on recirculation with a "strong pilot" going throughout the mash. sometimes i fire up the burner for a minute or two in addition, but with a 5 degree drop over 60 minutes, I wouldn't even be concerned.

Initial plan is to go with 2 layers of aluminum roofers flashing, and use screws and nuts over rivets. I do have 3 questions though.

Did you cover both sides of the insulation with aluminum sheeting, or just the outer side, letting the inner side of the insulation butt up against the keg?

What type of adhesive works best? Would you recommend the same adhesive you used or something else. I don't plan on having to take it off anymore than you, if at all.

thanks

 

[Bobby_M]

The raw mineral wool touches the keg. The side that touches the flashing received a coating of 3M super 88 and so did the flashing. If you don't plan to take it apart much ( haven't yet), then adhesive is not necessary. The key is to keep wort and water out of the mineral wool.

 

[caskconditioned]

Brilliant Bobby! I'm going all electric but I'm still planning on doing the "Bobby_M Insulation" to all my vessels as I think it looks a lot better than what I presently have (aluminum bubble wrap). Thanks for the idea.

 

[BucksPA]

thanks so much for the clarification. I look forward to receiving the sightglasses I ordered from you today = no more measuring with a stick, etc.

cheers

 

[HossTheGreat]

Anyone have any experience with the mineral wool with the wire mesh backing on it? I know it's 3x the cost, but I was thinking about using that and just fastening it to the keg using ratchet straps or bunjee cords. Do you all think that the mesh will give it enough structural support to keep it from breaking apart?

 

[Bobby_M]

I doubt it. The wool wants to disintegrate into tiny pieces if you look at it the wrong way.

 

[kotti270]

Hey I found this site if anyone wants to check it out. Some custom cut sheeting for like 5 dollars more that flashing.

https://www.metalbytheinch.com/t0/c135/3003-h14_aluminum_sheet.html

 

[berrywise]

Bobby,

Over a year later how is your setup holding up?

 

[matiasek]

I just stumbled across this thread. I am interested in giving this a try.

I tried the reflectix and aluminum tape a year ago, and ran into melting issues when heating my strike water. Not only that but the fumes that came off the solvents in the tape were horrible! Never again! I have considered rigging up reflectix with velcro and not tape this time but this post looks promising.

Bobby, how stinky has this new setup been? Silicone is stinky when first applied but usually fades, but I have never heated it before. How about that 3M adhesive and mineral wool? Has the seal maintained overtime?

thanks!
Mike

 

[Bobby_M]

It's holding up like a beast. Honestly the most wear and tear it has seen so far is the random interested party poking at the silicone seal at the top to try to figure out what it is. My previous solution was doubled reflectix with velcro but even thought it was easy to remove didn't mean I'd remember to remove it when the flame was lit.

I have not removed the insulation or metal wrap since it was installed as I've always just cleaned in place. It doesn't appear that the silicone seal has been compromised at all and I don't think the wool has gotten wet. The silicone smelled solventy when it was first applied but it was gone within a week. I don't notice any smells at all during heating. The very bottom layer of wool is exposed to the heat but it doesn't flinch or smolder.

 

[Maltose]

I could probably start my own thread, but Bobby maybe you can answer this. I've got an E-HERMS and want to insulate my mash tun. My three options are:

1. Your aluminum armored insulation
2. Reflectix
3. the adhesive backed foam insulation from McMaster

What would you recommend as my best option? The vessel is a keggle.