Grain Mill recommendations and grain crush for Brewzilla Gen4

[The Baron]

Hi I have just been prompted with a few threads that have said that the Brewzilla Gen4 has got to be used at full throttle on the pump so as to get a even temperature in the mash.
Now I know another member and I do apologise I can not remember their name at the moment is looking at lifting the grain basket higher to make the wort amount below the basket more so that there is more volume for the pump to be used on full.
Now I have the Gen4 and as with most owners it is not just a matter of taking it out of the box and expecting perfect brews ASAP so I have determined it is more critical to get the grain crush correct to enable quicker flow of the fluid through the grainbed as it has a smaller volume below this and a full flow can starve it if the mash is not flowing reasonably fast.
As I buy my grain pre-crushed I am at the mercy of the crush done by the supplier. This has not been too critical on my previous AIO but it seems to be important for flow on the Gen4.
So I am about to do a brew in a couple of days and have sieved the flour out of my grainbill of 3100 grams of base malt, this gave me 790 grams of waste flour- 25% (maybe I have been too zealous in sieving). I am going to see if this gives a better mash flow which in theory it should.
If this works I would then need to change my crush and the only way to do this properly would be to mill my own so recommendations without breaking the bank please members.
Ps I do have a low torque drill suitable for milling machines

 

[Caramel Ox]

I can’t believe that flour is waste…that’s a large part of your extract. There must be a control setup that works with less than 100% recirculating flow?

People seldom recommend any mill other than Grainfather, maybe wait for a good offer?

 

[The Baron]

They do recommend full throttle but as you have said CO I will do this brew without the flour I have removed also I will play with the flow rate too to see if it will operate without full throttle as my previous AIO did. I am looking to improve the crush to save on wastage too as I have only removed the flour as a exercise and do not intend wasting 25% each time hence the mill my own scenario

 

[foxy]

Hi I have just been prompted with a few threads that have said that the Brewzilla Gen4 has got to be used at full throttle on the pump so as to get a even temperature in the mash.
Now I know another member and I do apologise I can not remember their name at the moment is looking at lifting the grain basket higher to make the wort amount below the basket more so that there is more volume for the pump to be used on full.
Now I have the Gen4 and as with most owners it is not just a matter of taking it out of the box and expecting perfect brews ASAP so I have determined it is more critical to get the grain crush correct to enable quicker flow of the fluid through the grainbed as it has a smaller volume below this and a full flow can starve it if the mash is not flowing reasonably fast.
As I buy my grain pre-crushed I am at the mercy of the crush done by the supplier. This has not been too critical on my previous AIO but it seems to be important for flow on the Gen4.
So I am about to do a brew in a couple of days and have sieved the flour out of my grainbill of 3100 grams of base malt, this gave me 790 grams of waste flour- 25% (maybe I have been too zealous in sieving). I am going to see if this gives a better mash flow which in theory it should.
If this works I would then need to change my crush and the only way to do this properly would be to mill my own so recommendations without breaking the bank please members.
Ps I do have a low torque drill suitable for milling machines

That's a bit drastic, just make a more fluid mash and stir the mash. keep the grist from settling on the bottom, the flour will convert quickly. Have you insulated all your exposed pipework? 20 to 30 minutes the mash will be thinner as the starch converts to sugar. As long as you gently keep lifting the grist off the bottom of the malt pipe it should be fine.

 

[The Baron]

Did that Foxy 20ltrs in a 20 ltr brew so only 5 litres left to sparge and stirred loads of times but it still kept building up and the bottom emptying. All fully insulated with the Brewzilla jacket and pipe cover.
Just trying to get my head around it so seeing how much flow I can get with less flour in it.
I could add Oat husks but the grainbill is simple just 3100g od Pilsner and 250 of Torrified Wheat and as I added 200g of them to the last brew it did not do the trick still had to keep stirring to release the water back to the bottom reservoir several times
Ps the last brew was not a over large grainbill but it was a porter with plenty of adjuncts, crystal etc with a low DP of 34 so that may not have helped

 

[foxy]

Did that Foxy 20ltrs in a 20 ltr brew so only 5 litres left to sparge and stirred loads of times but it still kept building up and the bottom emptying. All fully insulated with the Brewzilla jacket and pipe cover.
Just trying to get my head around it so seeing how much flow I can get with less flour in it.
I could add Oat husks but the grainbill is simple just 3100g od Pilsner and 250 of Torrified Wheat and as I added 200g of them to the last brew it did not do the trick still had to keep stirring to release the water back to the bottom reservoir several times
Ps the last brew was not a over large grainbill but it was a porter with plenty of adjuncts, crystal etc with a low DP of 34 so that may not have helped

Yes, I realise it is a struggle with the G4 model narrow malt pipe and lack of space underneath the malt pipe. But if you can keep the grist in suspension for 20 minutes with full flow (should be easy with your next brew) it should settle and you can back the flow off.
Easy for me to say, I haven't used any AIO with such a small space under the malt pipe.

 

[The Baron]

The grainbill deffo did not help on that brew at all as it had allsorts in it and I stirred most of the time but left the pump on full flow which in hindsight I may have been better throttling back like I used to on my old AIO.
I am using this next brew as a experiment to try and get a rapid flow through the grainbed hence removed the flour. I think it is not as forgiving with graincrush as my previous AIO so it's time to start from basics and sort out the settings that will work with it.
I will probably get a mill to get more control over the crush which I think is more critical.
Lets see what this next brew brings
I still think the Gen4 is a good piece of kit it just needs to be treat differently as the reservoir is only just over 2 litres and with a pump is on full it soon empties.
I am awaiting I think it is Jambop?(sorry if wrong) doing a basket lift enhancement to get more reservoir at the bottom, infact as the next brew is going I may lift the basket and put a large rod through the 2 lifting holes and across the top(should lift it a good inch or so) to see for myself if this helps.

 

[RoomWithABrew]

Glucanase can help your mash flow.
Also whichever mill you get conditioning the grain can help the crush.
I really never had these problems with my robobrew 3, but the improved 4 seems challenging in many ways.

 

[The Baron]

Unfortunately am I right in Gluconase will ferment the beer lower? which is not what I want.
I will start to throttle the pump back contrary to advice from Kegland and hopefully find a crush that will enable a good mash flow.
I want to see what happens on my next brew to determine what settings etc will get it working better.
I am sure I will get it somewhere near what I want eventually just time and a challenge

 

[The Baron]

Right found a way of lifting the grain basket a inch or so that will increase the reservoir using the clamps that came with the unit volume for pumping

 

[foxy]

The grainbill deffo did not help on that brew at all as it had allsorts in it and I stirred most of the time but left the pump on full flow which in hindsight I may have been better throttling back like I used to on my old AIO.
I am using this next brew as a experiment to try and get a rapid flow through the grainbed hence removed the flour. I think it is not as forgiving with graincrush as my previous AIO so it's time to start from basics and sort out the settings that will work with it.
I will probably get a mill to get more control over the crush which I think is more critical.
Lets see what this next brew brings
I still think the Gen4 is a good piece of kit it just needs to be treat differently as the reservoir is only just over 2 litres and with a pump is on full it soon empties.
I am awaiting I think it is Jambop?(sorry if wrong) doing a basket lift enhancement to get more reservoir at the bottom, infact as the next brew is going I may lift the basket and put a large rod through the 2 lifting holes and across the top(should lift it a good inch or so) to see for myself if this helps.

I think you need to raise the basket, can't see any other way out of it. Drill two 3/8 holes directly opposite each other 3 inches below the lip. Get some 5/16 all thread with a couple of nuts cut the all thread so both sides are sitting on the support rim have the nuts on the inside of the grain basket to secure in position. Job done.

 

[The Baron]

The clamps I have used lift it about 1 inch so if I get a improvement I will then look at doing a more permanent fix like you have suggested.
I should get about a litre more in the bottom with this temporary fix but as you have suggested I think I will need at least double that

 

[RoomWithABrew]

Unfortunately am I right in Gluconase will ferment the beer lower? which is not what I want.

Fortunately you are wrong. Amylo glucosidase would be the enzyme to use in mash and fermenter to de branch the long starches to allow full fermentation. Useful in brut IPA / essential in that style.

Glucanase does this
" Barley 1,3-1,4-β-glucanases are heat inactivated during malting, which can cause the build-up of high molecular-weight glucans which in turn result in reduced extract yield, lower filtration rates, and even gelatinous precipitates in the finished product. As a remedy, heat-resistant bacterial 1,3-1,4-β-glucanases are added"

ie makes sticky glucans runny.

 

[Rodcx500z]

It seems to me the BZ Gen4 is not fit for perpose, you should not have all this palaver to get a machine to work, may be i am being over critical but i think i would be having a serious words with Kegland and supplier to get my money back, you should be able to use it straight out of the box, i know all these machines have faults but this one seems a nightmare, hope you get it sorted Baron

 

[foxy]

It seems to me the BZ Gen4 is not fit for perpose, you should not have all this palaver to get a machine to work, may be i am being over critical but i think i would be having a serious words with Kegland and supplier to get my money back, you should be able to use it straight out of the box, i know all these machines have faults but this one seems a nightmare, hope you get it sorted Baron

Well said Rod.

 

[borischarlton]

I think that the issue is that you are stirring the mash, this shouldn't be required. Whats more, it will force the fines through the false bottom and cause more issues. Are you sure that you are using enough mash liquor and how are you calculating that? If there is not enough mash liquor it will starve the pump and cause temperature issue as well potentially scorching the bottom.
When I use the Gen 4, I use the Grainfather G30 calculator to arrive at both mash and spare volumes. The ( free!! ) Grainfather app is very useful for a range of brewing systems.

 

[MashBag]

It seems to me the BZ Gen4 is not fit for perpose, you should not have all this palaver to get a machine to work, may be i am being over critical but i think i would be having a serious words with Kegland and supplier to get my money back, you should be able to use it straight out of the box, i know all these machines have faults but this one seems a nightmare, hope you get it sorted Baron

I like that sentiment and agree, but on balance how many people use these like a stainless BIAB and not as an AIO

 

[The Baron]

Fortunately you are wrong. Amylo glucosidase would be the enzyme to use in mash and fermenter to de branch the long starches to allow full fermentation. Useful in brut IPA / essential in that style.

Glucanase does this
" Barley 1,3-1,4-β-glucanases are heat inactivated during malting, which can cause the build-up of high molecular-weight glucans which in turn result in reduced extract yield, lower filtration rates, and even gelatinous precipitates in the finished product. As a remedy, heat-resistant bacterial 1,3-1,4-β-glucanases are added"

ie makes sticky glucans runny.

Thanks RWAB I wasn't sure but sounds like a helpful option
Will look into getting some where is best place and how much should I use in a standard brew?

 

[The Baron]

I think that the issue is that you are stirring the mash, this shouldn't be required. Whats more, it will force the fines through the false bottom and cause more issues. Are you sure that you are using enough mash liquor and how are you calculating that? If there is not enough mash liquor it will starve the pump and cause temperature issue as well potentially scorching the bottom.
When I use the Gen 4, I use the Grainfather G30 calculator to arrive at both mash and spare volumes. The ( free!! ) Grainfather app is very useful for a range of brewing systems.

I generally mash with 20 litres for a 20litre batch so plenty of liquid in there. I have stirred when only essential i.e when the pump is starting to slow and the level rise just like on my previous AIO and I have also stirred more than normal neither has settled the mash down as it should.
In my opinion the Gen4 is more susceptible and less forgiving on the crush of grain

 

[The Baron]

REPORT
I have this afternoon done the mash and mash out for the brew with the grain bill that has the flour sieved out and the malt pipe lifted about a inch.
It went near perfect, the pump was run on full all the way through the mash and mash out with no issues or mash level lift from lack of drainage.
As a result the temp was as it should be and never varied more than 0.5 degree either way.
So to me it does seem as the grain crush is critical and the pipe lift gave me at least another litre in the void to play with.
The machine is a very good implement it just needs to find a way to get around the flow and drainage issue. My method was a bit drastic but I needed to prove that the main issue was mash flow/crush size which in my mind I believe or have convinced myself it is.
Now I have quite a few sacks of grain that has been pre-crushed and need to use it so looking at using Gluconase as suggested by Room with a Brew to help with mash flow.
Ps best place to buy Gluconase?