Building a Lauter Mash Tun
How to build a mash tun / lauter tun from a picnic cooler
So you’ve done a few extract/kit brews and your ready to go all grain. If you’re like us, you’ve searched the internet unsuccessfully looking for what equipment/tools you will need. Because of this, we have taken the time to easily describe how we built ours. This is no means the best mash tun / lauter tun you’ve ever seen, but it gets the job done. Grain free drain. Easy to assemble. Easy to clean. If you decide to go cylinder cooler, you will need another source for how to build the manifold (draining pipes), but this should suffice for the nozzle. Let us know what you think. Feedback is welcome. We want to improve ours as well. You can get all this at a Lowe’s or Home Depot.
You will need 3 components:
1. 48 qt. cooler with drain (some believe cylinder works better – but I can assure rectangle gets it done)
2. Manifold to separate liquid from grain (~$15)
3. Nozzle / spout to drain liquid (~$15)
Instructions:
Cooler
1. Get a 48 qt. cooler. Take out the nozzle off the cooler. Save the inner seal from the cooler (see picture below).
Manifold
1. Purchase the following parts pictured below
2. Cut the CPVC pipe into the following dimensions (sizes made to fit standard 48 qt. rectangular cooler).
- E. Three pieces 1 in.
- F. Four pieces 1 ½ in.
- G. One piece 2 ¾ in.
3. After cutting the pipe pieces and slits, you will need to use brush (pictured above) to remove shavings. We also recommend washing vigorously or in a dishwasher
4. Assemble the manifold using the diagram below. Connect very tightly. When assembled, place in the cooler with slits facing the bottom on the cooler. I have read some posts recommending keeping slits facing up, but the majority of mashers recommend facing them downwards as grain will not defy gravity and flow up.
Nozzle / Spout
1. Purchase the following parts pictured below
2. Assemble the spout as such. Make sure it is very tight.
3. Connect to manifold.
4. Make Beer








about 5 months ago
The tap is on the *inside* of the cooler wall??? Must be a mistake.
Very good instructions otherwise though. Thanks!
about 5 months ago
Hi Damian,
Good catch. Thanks for the comment. I have updated the post.
Also – we have noticed that prolonged soaking in bleach is starting to mildly corrode the brass, so going to stop using and start using Star San.
Cheers!
about 1 month ago
Great directions, is CPVC ok to use? Most other directions I’ve seen calls for copper.
about 1 month ago
Hi Mike, thanks for the comment. From everything I read CPVC is safe for use in mashing as long as you don’t intend to boil it. Our CPVC is in a cooler mash tun, not a mash tun that we can add heat to.
Found this on a quick search. “CPVC piping which is suitable for hot and cold water distribution has a 400 psi pressure rating at room temperature, and a 100 psi pressure rating at 180 F”. With mashing, temps should not be above 155, so good here.
People don’t use PVC because it has a lower boiling point than CPVC and can leave off flavors in your mash / wort. Copper is great, we just preferred CPVC because it is easlier to work with. Easy to saw through, drill holes, and flex in the mash tun.
Good post here on PVC vs. CPVC – http://www.homebrewtalk.com/f51/sched-40-vs-cpvc-lauter-manifold-172912/
Cheers!
Brady and Brett