Cheap & Easy 10 Gallon Rubbermaid MLT Conversion

I don't understand why people wouldn't use a bazooka screen for $5 more than the SS braided hose costs. You can get one from bargain fittings for $17, it is rigid, and it has a 1/2" male fitting that screws directly into a ball valve.

 

No I haven't, I've built the system for this thread that you are posting in. It was easy, you even have the exact part numbers which is amazing, and it works great.

 

I think 'cos most people (myself included) use 3/8" fittings for these MLT conversions?

 

Hmmm...apparently they're $22
http://www.bargainfittings.com/inde...t&keyword=screen&category_id=0&product_id=171

Which is $16 more than i paid for the SS braid.

 

Hummm... fruit pies!! Thanks!

 

Gotcha...they must've been on sale when I ordered mine.

 

I think the other appeal of the braid is that you can pick it up locally and don't have to wait for the online order to show up. Although if I get another collapsed braid, I will be ordring one.

 

How much grain are we talking about to collapse the braid?

I have a 5 gallon Rubbermaid that I have yet to use. That size MT can realistically really only handle about 12 lbs of grain...will/can that weight collapse a SS braid?

Nick

 

I'm not sure how you guys are collapsing these braids... I've had this thing completely packed several times now, stirring it like a bad boy and the braid still looks perfect. Is it possible that you're smashing the braid with your mash paddle somehow?

 

I don't think it was the weight of the grain. I used a longer hose from a water heater and it curled in the cooler a bit. I think that I probably pulled on it with my mash paddle and caused it to constrict just short of the nipple. I haven't had a problem since I shortened it up. I also wire tied it over the entire fitting, flush with the cooler wall to try to keep it a little wider at the fitting.

 

I've made a 5 gallon and 10 gallon rubbermade mash tun and have found that the 10 gallon doesn't hold heat nearly as well as the 5 gallon version. It's not a headspace issue either, I typically fill them to the top with water and grains. The 5 gallon cooler typically lost about 2 degrees during the 1 hour mash and I've noticed the 10 gallon loses a good 6 degrees during a one hour mash. Anyone else notice this?

 

I think it's really more of an issue over time due mainly to stirring. My first braid was fine for about 10 brews then started getting all stretched and oddly shaped. It worked fine and I didn't really worry about it. Then one day I decided to change how my braid sat in there and figured I'd get a spring to put in the braid to ensure it'll last forever.

 

I lose about a degree in mine (rubbermaid) and I can see that some of the insulation is a little warped. Do you cover your lid with a heavy blanket/couple of towels? I do that every time and the towels actually get a little warm so I assume it makes a big difference.

 

I have a 10 gallon rubbermaid. I have only done 4 batches in it but have never lost more than 2 degrees over a 60 minute mash. I don't cover with blankets but I am brewing outside in Florida so the outside temperature is relatively high.

 

I haven't covered my lid with blankets yet. I'll try that next time and may even wrap one around the sides. It's been in the 60s the last couple times I used it. And after only 3 batches, the inside is pretty warped.

 

I want to build this setup, but with 1/2" fittings instead.

Anybody have a parts list for this? Particularly the O-Ring and fender washers I will need?

 

I did a test this past weekend and the 10 gal Rubbermaid lost about 5-6 degrees an hour over the period of a few hours with about 5 gallons of mash temp water. What I found most interesting is that the water near the top was much cooler than water at depth.

Next brew I think I'll do the blanket cover. I also need to look into expanding foam into the lid.

 

I think you will find that at least 4 of those degrees were lost in the first 10 minutes, with the other 2 drifting over the length of your test. When I do a mash in this thing after preheating it I barely lose a half degree over an hour. That is strange about the water being cooler at the top, since heat rises.

 

That is strange, but what I considered was that with half of the cooler being air with an uninsulated lid, I figured heat was escaping out the top more than the sides and bottom. And by cooler, it's no more than a degree. The thing about my tests is that I had that 5 gallons sitting there in the cooler for about 4 hours. It was by no means scientific, but I had just done a brew where I lost about 4-5 degrees over the hour, so I wanted to see what the cooler was actually losing without my interference. Turns out it was about the same.

What I've been doing to preheat is to make strike water and fill the MT for 10-15 minutes.... to then empty it back into the HLT and reheat. I think that's losing me a few degrees right there. Instead, I think I'll leave half the hot water in the MT and reheat in the HLT as needed to bring it back up. Any fine temp control can be done by adding small amounts of hot/cold water, stirring, etc.

Edit: Here's an earlier post where somebody has filled the lid with expanding foam - seems like that + wrapping in blankets helps:
http://www.homebrewtalk.com/f51/che...lt-conversion-23008/index153.html#post2754307

 

I'm doing one with all 1/2" fittings and a rectangular cooler but I can post the parts list when it's done if that would be helpful.

As far as the washers/o-rings go I'm using the 3/4" ones. I couldn't find the washers in stainless steel so i tried to just use them on the outside but I'm not sure it's gonna work. The size seems right though.

 

The thermal mass is all in the bottom where the grains collect, it's denser so holds temperature better.

 

I don't think the grains are denser than water... Taking a scientific angle, they are probably insulating and restricting the heat from transferring upward if anything. Now I'm really geeking out on this though, and want to get a thermometer with a 18" probe to find out.

 

Ok I'm new to all grain and I have like 3 1 gallon batches under my belt. What does this do exactly? I am going to read this entire thread but I have seen pics of these gatorade coolers and I'm lost.

Do you dump the grains into the cooler after you mash out and then do the sparge process by dumping the hot water into the cooler and let it steep in the MLT? Then transfer to your primary? Sorry big Newb here.

 

The quick answer is that you put your dry, cracked grains in the mash tun. Dump the hot water over them at the desired temp and volume. Let the grains steep to extract the sugars for the wort, usually 60 mins. Drain the wort from the mash tun into your brew kettle through a filter and then you begin your boil. By filter I mean something like the stainless steel mesh or hose braid that is only intended to keep the grains from flowing out into your brew kettle.

There is obviously quite a bit more going on in the mash tun and you can do multiple adds of water at multiple temperatures to achieve the desired result for your particular recipe. You can learn about all that on many of the other technique and recipe threads though.

Cheers,

 

Nothing wrong with being a Newb.

This vessel is where the mash rest takes place, and it also serves as your lautering vessel. You put your grains and (heated) mash water in here, close the lid and let it rest for whatever length of time your recipe calls for. At the end of your mash rest you drain the wort out through the ball valve into your kettle, add your (heated) sparge water, wait about 10 minutes and drain that out into your kettle, too. I don't know if that answers all of your questions, but I hope it helped!

 

Awesome makes sense now. I think I can do this. Then once the mash & sparge are done then you go ahead and do your normal boil, add hops, etc. Sounds like a mess free process. One of the instructions I have said to mix the mash every 10 mins or so. So I assume this step isnt necessary? Just keep the lid close, take an occasional temp? Then if the temp falls below where you want it then add some more hot water? I assume these coolers retain heat well for the 60-75 mins.

Thanks dudes!

 

They retain heat extremely well. You will usually only lose somewhere around 1-2 degrees, but if its a larger mash not even that much. A word of advice though, add the water first, not the grains. If you add water that's about 170, let it sit in the tun for 10 minutes, it will preheat the walls nicely and your dough-in will be much more stable temp wise. This technique will make your temp a little high at first, but you can stir, wait a minute, add a little cool water maybe and you're golden. Its WAY easier to adjust down with this system than up. Going up is a pain.

 

I am in the middle of building one of these cooler tuns with the 10 gallon cooler from home depot. I basically built it to match the original instructions. I have a couple quick questions that I wasn't able to locate the answers to in the 187 pages of this epic thread.

Will zipties work to attach the braid to the plumbing? I saw someone say that is what they used them but I haven't seen any updates as to how it is holding up. I tried some stainless steel cable ties that I picked up at lowes but was unable to get them tight enough.

Is it normal for all the fittings to spin freely? I tightened as best I could but I can still spin the plumbing easily. I don't think I am leaking but it just doesn't seem too sturdy. I am not sure if I can get things taken apart again to add another washer if that is what I have to do.

Hopefully I can get this put together for my first all grain session on Sunday.

Thanks.

 

^^ I can spin my setup freely, and it holds water tight. Used it 12 times so far without a drip. Why don't you want to use SS hose clamps?

 

FYI - For those of you wanting to build a 5 gal version. Lowes has them for $21.88. I just got mine today.

 

I've done 3 batches in here and my temps are needing altering everytime, either with ice or more boiling water. I've reached and held temps after alterations to the initial water. I think it is the "Initial Mash Tun Temperature" setting in beersmith. What is everyone putting their temp at, default 72? I tried preheating and I tried without, had better results without because beersmith was calibrated to 72. What is the initial temp of a preheated cooler?

 

I am weary of the ss hose clamps after the OP had trouble with them rusting. I checked with my local boating store but none of their ss clamps are small enough for what I need. Have you had any luck with the ss clamps yourself?

 

I used wire ties on mine with no problem.

I have had stuck sparges on my last two batches, though, and broke down and ordered a10" false bottom for $29.95. We'll see how that works out...

 

I've been using them no problem. Just make sure you clean and remove them to air dry when you're done with the brew day. I even did a few tests ahead of time by soaking them in water for a day or two to see of they would rust easily. They didn't. Even if they did start rusting, they are pretty cheap and easier to deal with than zip tie removal, IMO.

 

I've got to think they were nickle-plated non-SS clamps somehow. We use the SS ones in the machine shop, and they are put through all kinds of hell. Never once have I seen one rust. The ones in my MT are fine as well.

 

My clamps don't rust, they said SS on them so I figured they were fine... and they are!

 

Zip ties have worked fine for me and I've been using my setup for almost a year. Not syre why removal would be hard, you just have to snip them with a pair of wire cutters or scissors.
As for the freely spinning connections, mine have a little wiggle to them, but they don't spin. Of course, I used a slightly shorter nipple to go through the side of the cooler.
I've hit my target temps pretty consistently when I preheat my mash tun by filling it with hot tap water. I just run the water until it's at it's hottest and fill up the tun. Let it sit until my mash water is almost to tem and drain through the ball valve. Never had a mash that I missed the temp on by more than a degree or so.
I've also done overnight mashes in this with a cheap sleeping bag wrapped around it and lost about 4 degrees in 8 hours. I did make one modification, though. I drilled a small hole in each segment of the top and filled it with Great Stuff to insulate the top a little better. Works wonders.

 

What I do is I heat my water to about 5-8 degrees hotter than what i need, throw it in the MLT, and close the lid. I let the MLT heat up for a bit. Then I take the lid off and let it cool off to the temp i need (~165ish). Then I add grains. My MLT is based on the design from this thread. I can hold my temperature without dropping a single degree for an hour.

 

That's a pretty good idea. I may try that this weekend even though I'm not brewing to see how much of a change I get and how fast. I'm also curious to see how well my partial lid insulation works (ran out of expanding foam) vs using a down comforter.

 

Wow, great instructions. It took me 5 times longer to find and buy the parts as it did to actually do the build. Thanks for posting.

Like others, I was only able to find 5/8 fender washers in the build-a-bolt package at Home Depot. And they are Zinc, not stainless. I'll check Ace tomorrow. And who knew, I have a Fastenal about five miles from my house. Only open M-F though.