Plastic fermenter mash tun

I’m sure someone has done this before, but I have been using this for quite a few brews lately and it has some advantages.  I have other mash tuns in stainless, false bottoms, etc, but this is pretty good for grists <10kg.  This is only really useful for HERMS type setups.


There are some details that make it work well so I figured I’m put them here.

I use the heavy duty braid that Nev sells.  This stuff has similar qualities to that you can remove from the Bunnings hook up hose or whatever but the individual threads are a lot thicker.  You can actually stand on this braid and it won’t crush.  That isn’t really essential for this application though.  The other major part is this stainless plate:


This goes over the braid like so:


The plate has an interesting effect on the flow of the system.  It stops the weight of the grist resting on the braid itself – little bits of grain will flow and collect around the braid, but it isn’t crushed on there from above like it would be normally.   Even though it would appear to block access to a lot of the braid, I get much more consistent flow with the plate on there, and it never gets stuck even at high flow rates.  Another minor benefit is there is no longer that dead space of grain that never seems to lauter out properly at the bottom.  The bent corners of the plate are just big enough so the top of the plate rests slightly above the braid.

The other detail is the outlet tube.  I just have a normal fermenter tap, modified like so:


There is a short slice of heavy duty silicon hose wrapped around a small section of 1/2″ copper pipe.  It just so happens that between the two, it forms a perfect wedged-in seal.  I put the silicon hose in first, leaving about 6mm sticking out the end.  Put a little keg lube on the copper pipe and stuff it all together.  It fits very snug and doesn’t leak air when the pump is sucking on the end.  I just use a wingnut hose clamp with HD silicon hose attached to the tap nozzle to feed to the pump.

Anyhow I like the fermenter mash tun because it is a good shape for one – tall means the wort is spread over a small area, helping with lautering efficiency.  Also it is lightweight compared to big stainless items – easy one handed lug to empty out the spent grain.  I can fit about 9-10kg of grain in here, so good for 40-50L brews.

Another advantage – when lautering, you can actually see the level of the liquid through the plastic as it drains below the grain bed.

I’m not saying it is the most awesome or bling-est mash tun out there, but I’m finding it pretty convenient.

Leave a Reply

Your email address will not be published. Required fields are marked *