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Cheap & Easy 10 Gallon Rubbermaid MLT Conversion

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Is this safe for mashing? In order to get a firm seal in my converted cooler I had to use a 3 inch diameter rubber washer fitted around the pipe inside the cooler. I used some food safe silicon caulk between the side of the cooler and the on the washer. I couldn't get this to seal by just using the SS washers because of the pipe size being 1/2 inch instead of 3/8 in.

Will the rubber washer used to seal this affect the chemistry of the mash?
 
Well, there's a funny story about that, actually...

I wound up having to go out and find a stainless steel 5/8" washer anyways. Upon adding hot water to the mash tun to preheat it, the rubber washer deformed and the whole thing began leaking like a sieve. So no, rubber washers are not safe for mashing. Rigid nylon would be, but not rubber. I wound up finding a build-a-bolt kit in stainless that I used the washers from.

On top of that, though, I found out that the whole thing cracked around the inside. The whole way around. I think my pre-heat water was too hot, and caused the plastic to buckle and crack. So now I need to silicone it before using it again...Either that or buy a new cooler...Not sure I want to spend that kind of money right now, but we'll see. I'll probably buy the silicone later this week and seal it, then wash it out a few times with soap and water before next brewday in two weeks or so.
 
"On top of that, though, I found out that the whole thing cracked around the inside."

Return it and get a refund or a replacement. It should not crack with hot water 200' >. Montanaandy
 
Thanks for advising me about not using the rubber washers. I may just have to get a new cooler to try to use instead of this one I bought at a garage sale for $3.00. Anyone have an opinion on using a cylindrical cooler (like Rubbermaid) versus a rectangular cooler?
 
Thanks for advising me about not using the rubber washers. I may just have to get a new cooler to try to use instead of this one I bought at a garage sale for $3.00. Anyone have an opinion on using a cylindrical cooler (like Rubbermaid) versus a rectangular cooler?

Both coolers will work fine. I prefer the cylindrical b/c I could just buy a SS false bottom and not have to build a manifold to get good drainage. Some folks just use a SS braid, but I can't imagine it would be nearly as efficient as a false bottom or a properly built manifold

Oh yeah, and IMHO cylindrical=better for fly sparge
rectangular=easier to batch sparge
 
I finally made it out to Fastenal and bought the SS Washer (pack of 10).

I've got to get these built soon (MLT and HLT) so I can brew my American Cream Ale from Northern Brewer.

Really looking forward to brewing my first batch of AG.
 
hey guys just picked up a 10 gallon rubbermaid water jug. is this the same as the orange beverage cooler. it is red. has anyone used one of these for the mlt? dont know if it is insulated the same??
thanks
Buck
 
illinoisbuck,

I have the same one. Converted it last weekend and used it for the first time today. Worked great.

[edit] Added photo. There's the MT sitting on top of my new freezer! Today was my first all grain and first batch to go into the freezer.

mt_small.jpg
 
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!
 
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.
 
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.
Are you batch sparging or fly sparging? And no, the coolers should have a flat bottom, unless it got warped from hot water.
 
Fly sparging. And thanks for the info, it lends some credence to my assumption that altitude may be a factor.

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.

:mug:
 
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!!
 
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!!

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
 
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.
 
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.

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?
 

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