QldKev's New Biab With Internal Rims

[Matplat]

I had thought that the slow flow rate at the beginning was caused by the starches in the mash at the beginning being more viscous, then as the enzymes do their thing breaking down long chains into shorter ones that it becomes less viscous and thus flows quicker....?

I have to say this is my only dislike of the system, I have to monitor the level in the malt pipe constantly to check it isnt about to overflow, or that the top of the bed has become exposed.... I find it usually takes around 30-40mins to be able to reach a consistent flow rate...

While I'm at it, Kev, I've been meaning to ask you if you could post a photo of the terminal blocks you used on your 2kw element. I'm thinking of adding a similar one to mine to boost power to 3.6kw, for ramping and a more vigorous boil.... I know I saw a photo somewhere, but have searched the entire thread and couldn't find it.

Cheers, Matt

 

[malt junkie]

Think about it like this. When grain is wet it expands as it absorbs liquid, this absorbtion isn't instantaneous. What your trying to avoid is compacting or sticking the grain bed. The steps to avoid these issues are the same for every recirculating mash system.

 

[QldKev]

I think there are several things going on when we mash in. The less viscous starch chains, the swelling of the grains as they take on water, and as the grain bed settles into a grain bed that allows water/wort flow through out of it to act as a filter bed to clarify the wort and not getting sucked down into a solid lump. I find within 5 - 10min I can get a decent flow. I tend to fire up the system slow and walk away for 5 or so mins, come back do a second level flow for another 5mins, then open it up for the main mash. With vols I used to be worry about monitoring it from a dry grain bed/over flowing, but now I tend to mash in with a slightly low water level then top up once the grain is in.

For the terminal blocks etc, here some random pics of the system
http://s988.photobucket.com/user/QldKev/library/1V

 

[Hefty]

Phew, made it through all the awesome info in this thread to date!
I'm looking to make a system using a 40L crown urn and a 19L big W pot. I already have them from previous brewing set ups. Eventually I'm looking to use a Matho's/Lael's/ardbir type controller but I'm going to start with an STC for now.
Questions:
1. The pot, if I remove the handles, will fit inside the urn, but only just. There is about 1 cm on either side of the inner pot. Is this enough?
2. How do people determine how high to sit their inner pot from the bottom of the urn/kettle. I'll only be making 19-23L single batches. How do I calculate what length of legs/bolts/whatever to get the top of the pot at the right height for the batch volume to fit but not overflow?
3. The urn is made from really thin stainless. Without grabbing, warping or buckling the steel, how have people drilled holes for intakes, outlets etc? hole saw? Spade bit? Any tips on the actual process?

Cheers,
Jono.

 

[Chap]

Im looking at building the exact same system as Jono above and also am a bit wary of drilling into the urn. Pro tips greatly appreciated.
On a side note, my urn has a concealed element, so would it still be necessary for a bottom return inlet for the recirc?
Cheers
Chap

 

[hairydog]

Gday Chap,

I have been using a 40L urn with a malt basket made from ss mesh (thanks rooster boy),I pump the wort
and split the pumps output with one line having a ball valve, one line in the basket to keep an even temperature and one line to the element this helps keep the element from scorching too much especially when using rye and keeps the wort moving around the element.I use my sensor at the point where the wort enters the mash with a T piece and a RTD probed used a 20mm step drill nice and easy at a fairly slow speed with no hassles, check eBay they are sold at quite a good price.I have checked my wort temperature with a thermopen and its pretty well spot on with my PID temp controller.

 

[Hefty]

Did my first water test yesterday! A few minor leaks fixed and it ramps approx 1 degree per minute with plain water. I presume it will be a little slower in a mash. Can't find a spot to host my video but there's a few after thought photos attached.

The first one is of an old stainless barbed elbow I had. A few wraps of tape and my temp probe is a good "shove" fit until my thermowell arrives from Ali express.
Qldkev, thanks for your recommendation of 2014online on eBay. Only about 20 dollars more expensive than brass fittings from Bunnings for full stainless and they arrived 2 days before eBay's earliest postage estimates!!
Now just gotta get some ingredients and get brewing!
Cheers!
Jono.