Mash Mixing

[CaptainEBC]

I have a direct fired 3 BBL Mash Kettle that I will be mounting a geared down 1 HP VFD driven motor to for mash mixing. I was wondering about mixing RPMs and blade design. The key is to get the mash moving to avoid scorching.

Any advice is great. Thanks.

[Ted Briggs]

The blades should have a angle on them to lift the mash as they turn, but be 3-4 inches off the plates but close to the sides. Assuming your Vfd can reverse? If run in reverse they should push the grain down and out for you.
Not sure about rpm- but i would try to avoid excess shear force on the grain or mixing air into the mash. IE- as slow as you can while getting the mixing you need.

[CaptainEBC]

Here is a picture of my current design. I'll probably spin this around 60 rpm to get a tip velocity of 6 ft/sec.

[lhall]

I think that is too fast. Unless you are running a super thin mash, you won't be able to rotate through a normal mash at that speed with the size motor and gear box you show, IMO.

[Capt. Bob]

Quit over-engineering and just stir with a canoe paddle!

[sbradt]

too fast

I think that is too fast. Unless you are running a super thin mash, you won't be able to rotate through a normal mash at that speed with the size motor and gear box you show, IMO.

I would agree. You'll end up beating the crap out of your mash and having issues with sticking in the lauter

[theburden]

3bbls and you have an auto mixer? I remember years of 15bbls hand paddle mixing. I guess if you have the time and money, but really?

[CaptainEBC]

I'm an automation engineer by trade. It's hard to avoid not building things like this..........we also have a PLC and a 15" touch screen.

Everyone knows that flashing lights and buttons makes the beer taste better.

[gitchegumee]

Not only will you have to clean the damn thing every time you brew, you'll also have to keep it working properly. Couple those with the cost of install and it's hard for the Luddites not to win. I'm with those who'd rather rely on my own two hands and a paddle to mix and ascertain thickness.

[MikeRoy]

+1

+1

+1


From someone who has hand stirred 15bbl mash tuns with a boat oar I think automating a 3 bbl mash tun to this extent is overkill.

Save your money to purchase a larger system for when you out grow your current.

[liammckenna]

'Struth man.

+1 on the need for a paddle.

Direct your innovative energies into the paddle.

Repeat this mantra as you stir: 'I will seek simple, elegant solutions to my beer processing problems.' You'll be fine.

Sometimes our inner engineer needs a time out.

Pax.

Liam

[rudge75]

You really want to avoid scorching your mash?

Don't stir.

Sure, use your trusty mash paddle to get rid of the dough balls and dry spots during mash in, but a properly performed infusion mash will float. And a floating mash is much more apt to give up the sugars than an overstirred mash that binds up your screens.

Why you'd be wasting your time on temperature stepping a mash for a 3 bbl system is beyond me. Ask yourself: what happens when you grow? You're just needlessly adding time to your brew day because in general the malts you buy won't need a temperature stepped mash whatsoever.

[fa50driver]

Captain,

Your 3bbl system sounds really impressive. But then again I have to carry 55lb bags of grain up a ladder and dump into a 20 bbl mash tun and stir by hand...

[South County]

Captain,

Your 3bbl system sounds really impressive. But then again I have to carry 55lb bags of grain up a ladder and dump into a 20 bbl mash tun and stir by hand...

Man you need some flex auger love! And to echo Linus 60 rpm is WAY to fast, are you brewing all lagers? I guess im confused as to why your running a mash/kettle as opposed to a "simple but elegant" as Liam puts it, mash/lauter? In the end even if you have a wort storage vessel (if i read your blog right) your still stuck with a 12-14 hour double brew day, plus to extra movements (mash transfers), maybe I'm missing something?!

[liammckenna]

My oar supplier of choice.

Pax.

Liam