QldKev's New Biab With Internal Rims

[Rambo]

No. If you don't count that I had already put the saw away.

 

[Barge]

Just wondering. I thought it might have provided some stability. I'm about as handy with a saw as I am with a welder so both options are probably a stretch.

 

[Syd]

C

 

[krausenhaus]

I've done the same thing. I built a frame out of some square tube and brackets, and to the pot I riveted on some flat hooks that I cut off some tea towel holders from bunnings. Here is an old photo of it from my original non-recirculating setup:



The handle is made from stainless rope with some tube at the ends, bent into hooks and attached with JB Weld. One of these failed recently and broke off so I'm trying to figure out a better solution to attach the handle. Not being able to weld sucks.

 

[krausenhaus]

Krausenhaus,

What did you use for your insulation?

Cheers

It's called Aeroflex and I got it from eBay. It's not particularly cheap. Also it tears pretty easily so I need to be careful with it. I glued it to the side of the kettle with Kwik Grip wallpaper glue.

 

[Moad]

Im having drainage issues with a 19L pot too. Slits and holes but maybe not enough.

I'm going to drill some more small holes, basically as many as I can fit. Does anyone use a top plate as insurance against grain escaping? I've considered using a bag but that defeats the purpose of the grain basket!

 

[Barge]

I'm wondering if the whirlpool action that you see in QldKev's videos provides some sort of suction or pressure differential between the top of the pipe and the bottom.

Are the people with draining issues only using a top return, or dual return without a whirlpool?

Does everyone with a whirlpool return have no issues with draining?

 

[QldKev]

I wonder if the drainage issue could be from a finer crush? What crush are you using / any pics?

 

[Moad]

I'm using 1.1 I think, good point though. I'll get some pics today and likely brew on it this week. I might start with more holes first and then look at crush, ideally I would keep the same crush as my 3v system.

 

[QldKev]

Being the same crush as the 3V, I'm thinking it may not be the cause.

This is my crush, 0.9mm using a mm2 (monster mill)

 

[dropbear85]

could have something to do with the amount of water used during the mash. I had a similar problem and after doing a bit of reading about the grainfather it turned out I was mashing with too much water.
I have found that you want the water level outside of the malt basket to be lower than on the inside. reason being it means that the water inside the malt basket has a greater head of pressure and forces the water through the grain. if both levels of water are the same then water will be drawn from the path of least resistance (outside of the basket).
may be a little controversial but the bottom return could be part of the problem as water is basically being returned to the inlet of the pump therefore not sucking the wort throughly the grain. I had a bottom return on the first system I built but found it worked better without one. as long as you have enough grain and water to fill the malt basket plus cover the element and go 3-4 inches up the outside of the basket your element will never run dry.

just a bit of food for thought

 

[Matplat]

In this post are some photos of the slots I cut in my bigW pot.

I generally flow 1-2l/min at the start of the mash, then flow increases to 6-8l/min as mash progresses....

 

[krausenhaus]

I have a whirlpool return. The bottom of my basket is a commercial false bottom that has shitloads of holes so I don't think drainage is the issue.

I always use rice hulls now and it flows beautifully, so I think the main issue with me is crush. I can't get a good crush right now because the rollers on my minimill are duds - I have to run it through at least twice and it's pretty pounded by the end of it.

I'm happy to use the hulls for now.

 

[Moad]

Anyone using the keg with 19L pot inside, how much water do you start with?

I ran a brew through this week to test it out, started with 23L for 5KG of grain which came about 1/3 - 1/2 way up the inner pot before any grain was added. When grain was in and circulating it dropped to almost the bottom of the inner pot (on the outside). My eff was only 65%

It didn't seem like the mash was too think, I did mash in too hot though and it may have denatured before conversion really got under way.

I'll brew again this week and start 25L of strike water, hopefully get a bit more than 65%

 

[CoxR]

Full volume for me

 

[Moad]

so what 35L? Does it not overfil the inner pot?

 

[QldKev]

I start about 25L, and hit 85% eff constantly. The crush and pH are keys.

 

[CoxR]

It will depend on the distance between the bottom of the keg and pot.
On mine the water and grain (5kg) will sit about 50-65mm from the top of the inner pot with the recirculation fully open.

 

[Moad]

Went with a coarser crush today and had no flow issues whatsoever but my efficiency was still 65%.

I have a feeling I need to go somewhere between the two. I was at 1mm originally and today 1.4mm. 1.2 might be the sweet spot.

 

[Moad]

Still not getting any better than 65% regardless of the crush. Might be time to start looking at pH

If I could simply throw more grain in I wouldn't worry too much but the small pot restricts me to 6KG