Robobrew stuck sparge

[Stewart Brewing]

Hi All,

Hoping for some advice from a long term Robobrewer.
Are you using the wire mesh in the bottom of the malt pipe?
I am finding that my sparges are getting stuck, no flow through the malt. The only way to get it moving is to repeatedly twist a paddle at the bottom of the pipe on the top of the wire screen. i feel like the wire screen is getting clogged with small malt particles / sugars.
Should I try a brew without the wire screen using only the punched hole base plate?

Any one else experienced this with the Gen 3?
Cheers

 

[cheeseyfeet]

I use the fine mesh and have had very slow run offs but never stuck.

I resolved this by starting to throw a couple of handfuls of rice or oat husks into the mash, works a treat!

 

[SteveH]

I've found you need to mash fairly thin or the problems you describe are likely - I generally mash in with 20l water for grain bills of up to around 5kg and that seems to work well.

 

[Stewart Brewing]

Thanks Cheesy and Steve, I'll look in to both.

 

[The Baron]

Stuck sparges are usually a sign of bad grain crush (too fine) or a large grainbill with a lot of wheat/rye porridge oats/and other grains. As said the best way to improve this is to mash with a higher amount of water 0f 4ltr per kilo up or down a bit, I usually mash for a standard 23ltr brew with 19ltrs and sparge to the pre boil amount I need. Another preventative is when using a larger amount of the suspect grains mentioned is to use Oat husks to give some separation in the mash also a stir or two helps say at 1/4 and 1/2 mash time but do not over stir as this can make the mash starchy and gloopy which will again accentuate the problem. I have found that it is usually the grain crush that causes the problem in ALL in one systems so not just the Robobrew but as you get to know your system you will work out the best way for yourself. Good Luck

 

[London]

Do you use the oat husks whole or crushed?

 

[The Baron]

Hi Oat husks come as they are it is the outer husk off the grain so it is supplied as is neither crushed or crushed if that makes sense

 

[London]

That's what i though but on the Malt Miller website that are options for uncrushed,crushed and fine crush

 

[The Baron]

Must be a technical hitch to do with general grain ordering as I have only ever bought it as is unless somebody knows different

 

[Keruso]

That's what i though but on the Malt Miller website that are options for uncrushed,crushed and fine crush

MM does offer uncrushed, crushed and fine crush for all malts and adjuncts, just click uncrushed for the husks but I don’t think MM will crush them whichever option you choose.

 

[Keruso]

Stuck sparges are usually a sign of bad grain crush (too fine) or a large grainbill with a lot of wheat/rye porridge oats/and other grains. As said the best way to improve this is to mash with a higher amount of water 0f 4ltr per kilo up or down a bit, I usually mash for a standard 23ltr brew with 19ltrs and sparge to the pre boil amount I need. Another preventative is when using a larger amount of the suspect grains mentioned is to use Oat husks to give some separation in the mash also a stir or two helps say at 1/4 and 1/2 mash time but do not over stir as this can make the mash starchy and gloopy which will again accentuate the problem. I have found that it is usually the grain crush that causes the problem in ALL in one systems so not just the Robobrew but as you get to know your system you will work out the best way for yourself. Good Luck

I find it’s the grain crush and the amount of visible flour. Every sticky mash I’ve had is when you can see lots of flour. I did an experiment and sifted it out, and got the best circulation ever, and crystal clear wort. You need to add more grain or dextrose to compensate for flour removed.

 

[Ghillie]

In no particular order:

18-20L strike water volume regardless.

Give your grain 15 minutes to rest after doughing in, will allow the grain bed to settle evenly.

When you turn your pump on, do it with the recirc arm valve closed, then gently throttle it open until you get a trickle. Build the flow up gradually until you're happy. Don't rush this part. Run the pump full chat straight away and you'll compact the grain bed to the point of it becoming a nightmare.

Dump the fine mesh screen from the bottom of the malt pipe.

Wet condition your grain (if crushing your own).

Mash out to decrease grain bed viscosity which will help with sparging.

 

[London]

Ghillie,
Do you mean 18-20L strike?

 

[Ghillie]

Ghillie,
Do you mean 18-20L strike?

I certainly did, edited to correct. Thanks for pointing that one out!

 

[Stewart Brewing]

Thanks all,
I have noticed some flour in the malt, I have ordered rice hulls.
I may have been over stirring the mash and turning it gloopy. I will watch out for this.
Slow start to the re-circulation noted.
Larger strike water volume.
Will be a few weeks until I will be brewing but I'll post an update.
Cheers

 

[the_quick]

Had similar problem, stopped using the secondary fine mesh for the bottom and it stopped that. Don't use any husks.

 

[Stewart Brewing]

Thanks Quick. Thinking about this option too.

 

[Alfie Noakes]

I just had this exact problem today, some flour in the Pilsener malt crushed by MM, horrendous mash that I had to keep stirring to get any flow through. Think I'll try without the fine mesh screen next time, might also try sifting the flour out of the grain, thanks everyone for their help here, was tearing my hair out this morning!

 

[Neil Whittaker]

I know this is a slightly old thread now, but it is exactly what I've experienced over the weekend.
Aimed for a Pre-boil of 1.044 got 1.022. :-(
-Brewzilla all in one system - Used the fine mesh.
-I had oat hulls mixed in 100g, which is a lot (maybe too much)
-Pilsener malt & pale malt, crushed by MM (Was a little fine)
-3L per KG of malt.

I read a few old threads and next time I think -
Going to ditch the fine mesh in the BrewZilla, I just hope this does not result in a blocked pump. (Had that before)
Make my mash even thinner 3.5l Per KG. Maybe even give the full mash with no spare a go at some point.
Fill my malt pipe and lower it slowly into my strike water. Let it rest for 15 minutes.
Only use 50g of oat hulls as 100g was a really large amount when weigh out. Add more during the mash if needed.
Maybe if the crush is to fine, sift some of the fine stuff out. Maybe add it again towards the end???
Take a SG reading before I raise the temp to mash out, then i can maybe do something about the efficiency before I ditch the grain.

I ditched nearly a kilo of brewing sugar in, I should have used Malt Extract. Hope my brew is drinkable.
All a learning process, was my first full capacity AG brew.

 

[foxy]

I know this is a slightly old thread now, but it is exactly what I've experienced over the weekend.
Aimed for a Pre-boil of 1.044 got 1.022. :-(
-Brewzilla all in one system - Used the fine mesh.
-I had oat hulls mixed in 100g, which is a lot (maybe too much)
-Pilsener malt & pale malt, crushed by MM (Was a little fine)
-3L per KG of malt.

I read a few old threads and next time I think -
Going to ditch the fine mesh in the BrewZilla, I just hope this does not result in a blocked pump. (Had that before)
Make my mash even thinner 3.5l Per KG. Maybe even give the full mash with no spare a go at some point.
Fill my malt pipe and lower it slowly into my strike water. Let it rest for 15 minutes.
Only use 50g of oat hulls as 100g was a really large amount when weigh out. Add more during the mash if needed.
Maybe if the crush is to fine, sift some of the fine stuff out. Maybe add it again towards the end???
Take a SG reading before I raise the temp to mash out, then i can maybe do something about the efficiency before I ditch the grain.

I ditched nearly a kilo of brewing sugar in, I should have used Malt Extract. Hope my brew is drinkable.
All a learning process, was my first full capacity AG brew.

What was the malt bill, you are certainly down on your gravity, full volume will work but means adding more grain. Finer grist will recirculate and get dumped on the top of the grain bed. I presume you are using brewing software.