Cheap & Easy 10 Gallon Rubbermaid MLT Conversion

Thanks again Flyguy for the post and excellent details for assembly.

I finally assembled mine yesterday and it looks/works great.

The only thing I did different was use a false bottom (from Northern Brewer) instead of the SS braid. Other than that -- it is identical.

I went ahead and built two (2) of them -- one as a MLT and the other as a HLT.

I got mine assembled yesterday as well, but have a small problem.

I had a VERY slow sparge during my first brew yesterday. I purchased a domed stainless false bottom, but the bottom of the cooler is domed as well, and it just about matches exactly the dome of the false bottom.

I guess I wonder if EVERY 10-gal rubbermaid has a domed bottom like this, or if it's just me?

I attribute this to the fact that I'm at about 6700 ft above sea level, and assume some air is trapped under the bottom that is causing it to "balloon" up. Has anyone else experienced this? I plan to try to surgically drill from the bottom up to release the pressure, but was wondering if anyone else has a similar issue. I've searched the forums and found someone else who had a slow sparge for what appeared to be similar reasons but didn't see anything in this thread yet.

Thanks!

What kind of efficiency are people seeing with their Rubbermaid MLT? I can't seem to get above a 65% with mine?

To pkphy39, I too live at 6700 ft and have not seen the bottom of my rubbermaid ballon up. Though I have heard of stories of people adding really hot strike/sparge water to their coolers and getting some warping of the liner. I would be VERY careful drilling up from the bottom b/c it would really be a bummer if you pierced the internal liner. Besides, drilling a hole in the bottom may not cure the problem, if the problem is warped plastic and not an air bubble. You may consider that your slow sparge was due to grain bed compaction; next time try slowing the rate of initial drain/vorlauf until your bed is set.

To Beernip, I'm getting 65 to 75% efficiency on my SS-braided Rubbermaid MLT for lower gravity beers, and 60 to 70% efficiency on higher gravity beers. After draining my initial mash I split the sparge into 2 equal volumes and sparge twice, draining between each one.

Cheers

KingKeg - thanks for the reply.

I should have noted - both of my rubbermaid coolers (MLT and HLT) have a ballooned bottom, and arrived in that condition (new).

The grain bed seemed fluffy, and during vorlauf I didn't open the ball valve fully until I saw I wasn't getting much flow - though it's entirely possible I did compact the bed; I will pay closer attention to the process next brew day.

I will drill VERY carefully (with a dremel, over which I'll have finer control) - the last thing I want to do is ruin my new equipment! But after springing for the false bottom I'd like the stuff to perform as intended.

I suppose I was hopeful that the addition of water and grain would push down the bubble, but obviously that didn't happen.

Thanks again for your response. Any other tips/experience with this problem would be welcome.

pkphy39 said:

I got mine assembled yesterday as well, but have a small problem.

I had a VERY slow sparge during my first brew yesterday. I purchased a domed stainless false bottom, but the bottom of the cooler is domed as well, and it just about matches exactly the dome of the false bottom.

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Are you batch sparging or fly sparging? And no, the coolers should have a flat bottom, unless it got warped from hot water.

Beernip said:

What kind of efficiency are people seeing with their Rubbermaid MLT? I can't seem to get above a 65% with mine?

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80 - 85% with a fine crush, typically.

See my signature below for some efficiency tips if you are batch sparging.

FlyGuy said:

Are you batch sparging or fly sparging? And no, the coolers should have a flat bottom, unless it got warped from hot water.

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Fly sparging. And thanks for the info, it lends some credence to my assumption that altitude may be a factor.

pkphy39 said:

Fly sparging. And thanks for the info, it lends some credence to my assumption that altitude may be a factor.

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If you dumped some boiling water in it and set something inside (e.g., a full corny keg), then let it cool, it might flatten out again. Hope you get it fixed without too much difficulty.

I just built this as my first DIY project. It was actually much easier than I was expecting. I'm not very mechanically-savvy, but I can follow directions... No leaks, drains perfectly.

I picked up a 10gal cooler at home depot. It has a big home depot logo on it instead of the usual rubbermaid one, but it was only $40 (I saw them elsewhere for $60-70). The parts were about $35, maybe $40. (When shipping is factored in, it was about as expensive as buying a kit from bargain fittings.)

I had difficulty finding the 5/8 SS fender washers -- actually I had difficulty finding 5/8 fender washers period. I did some substitution. I found 5/8 neoprene washers that are both waterproof and heat resistant. I used one on the inside in place of the SS washer. On the outside of the cooler, I used two neoprene fender washers with a 5/8 zinc cut washer in place of three fender washers. It isn't as steady as going all metal and twists a little in the rubber fitting on the inside when you turn it on and off, but there's no leaking after letting water sit for 30 min and not a drop when I turned it on and off.

Thanks a million to the OP and the clear directions and pictures on this!!

ReverseApacheMaster said:

I had difficulty finding the 5/8 SS fender washers -- actually I had difficulty finding 5/8 fender washers period. I did some substitution. I found 5/8 neoprene washers that are both waterproof and heat resistant. I used one on the inside in place of the SS washer. On the outside of the cooler, I used two neoprene fender washers with a 5/8 zinc cut washer in place of three fender washers. It isn't as steady as going all metal and twists a little in the rubber fitting on the inside when you turn it on and off, but there's no leaking after letting water sit for 30 min and not a drop when I turned it on and off.

Thanks a million to the OP and the clear directions and pictures on this!!

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I think it's actually in this thread somewhere, but there is a "build a bolt" package near the all-thread in the bolt/nut section of HD. In there are a bunch of SS 5/8 fender washers

This site sells 5/8" SS Washers by any amount you want. Shipping might be steep if you're only buying one or two, but they gots 'em!

So I tried buying the parts for this at Home Depot last night. They claim they no longer carry that size of ball valve, nor did they have any stainless steel washers for the inside of the cooler. I tried at True Value as well with no luck. Not sure where I'll find the correct ball valve size, the closest I could get was 1/4 inch which does not fit the other pieces. I also ended up using a rubber washer for the inside rather than stainless steel (do you guys think that is ok?) The guy at True Value thought the usual Nickel washers wouldn't be good to put inside the cooler. I'll have to keep searching for these hard to find parts. Hopefully I can get this thing built fairly soon.

steinsato said:

So I tried buying the parts for this at Home Depot last night. They claim they no longer carry that size of ball valve, nor did they have any stainless steel washers for the inside of the cooler. I tried at True Value as well with no luck. Not sure where I'll find the correct ball valve size, the closest I could get was 1/4 inch which does not fit the other pieces. I also ended up using a rubber washer for the inside rather than stainless steel (do you guys think that is ok?) The guy at True Value thought the usual Nickel washers wouldn't be good to put inside the cooler. I'll have to keep searching for these hard to find parts. Hopefully I can get this thing built fairly soon.

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www.bargainfittings.com

He's a HBT Vendor that I bought my 1/2" SS ball valve from my kettle, if I was to build a new HLT I'd buy from him.

How crucial is a stainless steel washer? WOuld a nickel washer be a really bad idea for the inside of the cooler? I see now that the rubber one I bought doesn't provide enough rigidity to the valve so when I try to turn the ball valve handle the entire piece wants to move around with it. I checked the www.bargainfittings.com site, unfortunately they do not carry 5/8" SS washers.

I personally wouldn't use Zinc because of corrosion, however both my MLT and HLT reuse some plastic parts from the original spigots. My Gott cooler reuses a nut from the inside as a washer and my rubbermaid reuses a vinyl washer.

I finally got mine put together today and it works great. Not leaking a drop.

After spending days searching in vain for a 5/8" SS washer, it dawned on me to try and find a "close enough" metric equivalent. Found a 16mm stainless steel fender washer at the first place I tried (Ace Hardware), fits like a glove. Cost me $1.70, but I spent twice that much in gas driving all over town looking for the imperial equivalent.

So for those on the washer hunt, be sure to check out the metric section too. You might have more luck there.

I built mine tonight and it works great. I had some of the same problems with parts and thought I might offer my solutions. I apologize if this is mentioned before.

I bought the Crown Bolt Create a Bolt kit in 5/8". There are two boxes of these at my HD. One is SS and the other is Zinc. I had to poke around but I found the SS ones. Keep looking through the packages, because they look identical minus a small note on the front that designates SS or Zinc. This came with 4 5/8" SS washers and I used all of them. I used 2 5/8" zinc flat washers for the outside spacers. I also added 2 neoprene 5/8" washers. These were in the specialty washers drawer at the HD.

For the spacers, I used the 2 zinc flat washers and 3 SS washers from the kit (since I wasn't going to use them for anything else) and I added a neoprene against the cooler. On the inside, I used the second neoprene, the original rubber seal, and a SS washer.

My HD also said they didn't carry a 3/8" ball valve. So, I bought the 1/2" ball valve and also bought 2 1/2" MIP x 3/8" FIP Pipe Hex Bushing (Watts A-828). I put these on both ends of the 1/2" valved effectivly necking it down to 3/8", which allowed me to use all the other parts without modification.

Also, the local HD did not have much in the way of SS supply hose. It was all polymer except one labeled universal dishwasher hose. The only downside is that it was $15 and came in one length, 60"! Guess I'll have plenty for replacement!

I had the same stainless steel washer problem as well. After a while I figured out that the plastic nut that was holding the original spout could be modified to work. I didn't have a 5/8ths drill bit so I ground off the nuts threads and a bit more with a dermal until it would fit over the brass pipe. It seems to work well with just two spacer washers on the other side.

Pics:
http://www.flickr.com/photos/48288027@N03/4423457477/in/photostream/

I also have a slightly different design for the stainless braid portion that I mostly got from John Palmer's book. It's a 1x24 inch braid that wraps in a circle to a T connector.

Just got back from the HD. 10 Gallon cooler is still 39 bucks.

Found almost everthing on the list.....(darn, forgot the high temp tubing. got to have a home brew now.......................)

ah.

OK

The Cut a Bolt kit that I saw clearly stated they were ZINC coated. I did not buy this and will hit the Fastenal store on the way home for the SS washer.

For the other 3 5/8 washers, I could only find what was called CUT washers in the 5/8 size. Although they aren't 'cut'. They are flat and a little thicker than the smaller sized Fender Washers. I saw Fender Washers but not in that size.

Is there a difference?

BendBrewer said:

Just got back from the HD. 10 Gallon cooler is still 39 bucks.

Found almost everthing on the list.....(darn, forgot the high temp tubing. got to have a home brew now.......................)

ah.

OK

The Cut a Bolt kit that I saw clearly stated they were ZINC coated. I did not buy this and will hit the Fastenal store on the way home for the SS washer.

For the other 3 5/8 washers, I could only find what was called CUT washers in the 5/8 size. Although they aren't 'cut'. They are flat and a little thicker than the smaller sized Fender Washers. I saw Fender Washers but not in that size.

Is there a difference?

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You definitely want the SS washer on the inside -- so I hope you found them at Fastenal.

Regarding the washers on the outside, they are just spacers to help tighten the fittings. Just use whatever works (it sounds like the ones you found should do the trick).

And regarding the high temp hose -- please re-read the thread. I no longer recommend using that AT ALL. More trouble than it is worth.

I hope the build all goes well, and that your first batch out of the new mash tun turns out fantastic!

Well thanks for the initial post and all the follow up that you have done regarding it Fly-Guy.

I'll pick up the SS washer on my way home. Put the rest of it together, Nothing Tightened, at my desk at work and realized those outside washers are going to work just fine.

Can you point me to a page number for the alternative to the high temp hose? I saw hose clamps didn't work and only noticed the hose as an alternative.

And, when are we going to hit the Deschutes?



Cheers!

My pleasure -- glad you found the info helpful!

If you can get all stainless hose clamps, they still work the best. I have since switched back to them. But if you can find rigid, high temp tubing, that stuff works like a charm. I got mine at Rona (sort of like a Lowes up here in Canada).

Regarding the Deschutes.... would LOVE to fish that sometime! Nice fish, BTW!!

Maybe I can reciprocate and take you to some good spots up north!

Likewise on the fish and you're on!!! Anytime.

SS hose clamps it is. 10 batches of PM brews and it looks like #11 will be an AG. Awesome job on this thread.

Tight lines!

Someone proposed zipties instead of hose clamps. I tried and they seem to work just fine.

I tackled a mash-tun build yesterday, but like many, I cannot find any 5'8" SS washers. Going to try a boating shop tomorrow. Perhaps they have some?

So I went out and got all the parts to convert my two ten gallon coolers into HLT & MLT. I planned on using this design for the bulkheads for both.

I ran into a "problem" though. Maybe its not a problem at all. I got the exact part numbers of the parts list. The 3/8" nipple is a lot smaller than the pre-drilled hole in my cooler. Its also a lot smaller than the rubber washer that came with the cooler so there is a lot of space between the outside diameter of the nipple and inside diameter of the rubber washer. About 1/8" all the way around.

How did everyone who used this design work around this problem? Are additional parts needed so that it won't leak? o-ring on the inside somehow?

I'm working with 2 ten gallon igloo coolers if that helps. Wondering if I need to take everything back and get half inch? or if I'm just missing something with how this all works?

One hundred and three PAGES worth of posts? Dude...FlyGuy... you da man!

Great fishing pics!

yeast_infection said:

I'm working with 2 ten gallon igloo coolers if that helps. Wondering if I need to take everything back and get half inch? or if I'm just missing something with how this all works?

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If the Igloo coolers have a hole and spigot gasket that is larger than the Rubbermaid, then by all means just upsize to 1/2" parts instead. The general design should still be the same.

My whole purpose in using the 3/8" parts was that they fit the Rubbermaid spigot gasket PERFECTLY. If your parts fit a 1/2" gasket, then that will work too (in fact, some might prefer the larger hardware, albeit slightly more expensive).

I actually put together Fly Guy's exact design yesterday and had all 3/8 parts but could've used 1/2 instead. What I did though was to use 1/16" thick rubber washers that had a 5/8 ID to fit right over the middle of the double male threaded piece. Put a rubber washer on either side and tightened it down on both sides. Filled it to the brim and let it sit for an hour and no leak to be found.

Brewed 30 minutes after that still great.

Thanks Fly Guy for all the info.

I got her to work lol. It cost me an extra $3 to return everything (all parts X 2 - MLT & HLT) and exchange the 3/8 for 1/2. Works like a charm. Used the same exact design only everything 1/2 rather than 3/8.

Can't wait to brew with em.

Does the configuration that Flyguy talks about here, also work at the top of the MLT if you intend on recirculating the wort with a pump? I'm concerned with the contour of the round cooler. Maybe a flat walled cooler would be easier to attached the higher inlet connection. Any thoughts?

BB

Some final touches on FlyGuy's MLT Clone. Thanks again! Hit 73% eff. on first batch.

I found some 5'8" SS washers today. Had to go to 2 nuts and bolts shops to find them

I had a hell of time getting mine to not leak out around the ball valve. I reused the original washer that came with the original spigot, SS washer and a couple outside. Tightened it so much the cooler was screeching. I ended up going to Lowe's and getting a 5/8" rubber grommet. I put this in the hole for the spigot, then did everything as instructed minus the factory rubber washer. NO LEAKS I am proud to say...

BendBrewer said:

Some final touches on FlyGuy's MLT Clone. Thanks again! Hit 73% eff. on first batch.

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Great looking mash tun! Let us know how that first batch goes.

snevey said:

I had a hell of time getting mine to not leak out around the ball valve. I reused the original washer that came with the original spigot, SS washer and a couple outside. Tightened it so much the cooler was screeching. I ended up going to Lowe's and getting a 5/8" rubber grommet. I put this in the hole for the spigot, then did everything as instructed minus the factory rubber washer. NO LEAKS I am proud to say...

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Actually, over-tightening is the leading cause of leaks. Did you try backing off a bit? I bet that was it.

Also, did you use teflon tape on the fittings? That's a must (for the nipple and ball valve at least).

kjjohns5 said:

I found some 5'8" SS washers today.

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Holy crap. How did you get them home?