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General Category => All Grain Brewing => Topic started by: bluedog on February 14, 2010, 04:33:18 PM

Title: Mash temperature differences
Post by: bluedog on February 14, 2010, 04:33:18 PM
Hi all,
When I mash I have a floating thermometer in the pot. I will get different readings if I check different spots. My question is if I take a sample of the liquid and the temperature is correct (let's say 152 F) does it matter if the temperature in the grain bed flucuates? I am stirring the grain in the mash tun every 5 minutes or so.
Title: Re: Mash temperature differences
Post by: weazletoe on February 14, 2010, 05:24:38 PM
  When you doe in, you need to do a really good stir, five mins or so. Then, what I do is use a digital thermometer, and stir with that. The temp varies by a bit, but as long as it is a close average, I'm happy with it.
Title: Re: Mash temperature differences
Post by: denny on February 14, 2010, 05:26:06 PM
I'm with Weaze....stir at dough in until you get consistent temps.  Then close the cooler and don't stir anymore.  Whenever you open it to stir, you lose heat.
Title: Re: Mash temperature differences
Post by: weazletoe on February 14, 2010, 05:28:53 PM
Technically, since I learned this method from you..

I'm with Denny.
Title: Re: Mash temperature differences
Post by: euge on February 17, 2010, 07:26:04 AM
Found out the hard way. Stir it till yer arm hurts and it doesn't hurt to leave the tun alone after that. A good spoon is good indeed. Stir it like crap again before you sparge.

And a good preheat is critical. Don't skimp.
Title: Re: Mash temperature differences
Post by: ndcube on February 17, 2010, 01:32:27 PM
I'm with Weaze....stir at dough in until you get consistent temps.  Then close the cooler and don't stir anymore.  Whenever you open it to stir, you lose heat.

That's what I do to.  Sometimes I'll open up for a pH sample.
Title: Re: Mash temperature differences
Post by: dhacker on February 17, 2010, 01:52:44 PM
OR . . .

Let the motors do the work and never open the lid!   :D

(http://i1013.photobucket.com/albums/af255/dhacker50/DSC01395.jpg)
Title: Re: Mash temperature differences
Post by: beerocd on February 17, 2010, 02:06:12 PM
OK,  how about a thread about your crazy cooler? Can't exactly make out what's going on with the manifold either, but now I'm interested...
Title: Re: Mash temperature differences
Post by: ndcube on February 17, 2010, 02:12:08 PM
I'd like to see more too.  From the pic it almost looks like the lid can't close b/c the props will hit the sides.
Title: Re: Mash temperature differences
Post by: dhacker on February 17, 2010, 02:47:22 PM
The lid will close as long as the bottom props are indexed in relation to the tun sides . . which can be done via the top shafts on the motor . . a quick spin and they will line up fine. 17 RPM stirs the mash the entire time before sparge . . spool 'em up during the sparge, stop and let it settle for a minute or so before lauter drain . . piece o' cake and no heat loss from opening the lid. The #8 copper wire spiraled onto the braid was originally done to add support, but I subsequently found it unnecessary

A few more pics of the system . . it has been updated some since I took these.

(http://i1013.photobucket.com/albums/af255/dhacker50/mash2.jpg)

(http://i1013.photobucket.com/albums/af255/dhacker50/mash1-1.jpg)

(http://i1013.photobucket.com/albums/af255/dhacker50/Tun1.jpg)

(http://i1013.photobucket.com/albums/af255/dhacker50/Tun4.jpg)

(http://i1013.photobucket.com/albums/af255/dhacker50/Rig2.jpg)



Title: Re: Mash temperature differences
Post by: denny on February 17, 2010, 04:13:30 PM
Some people are such friggin' overachievers!   ;)  Very cool!
Title: Re: Mash temperature differences
Post by: dean on February 17, 2010, 05:20:29 PM
Damn thats Pretty!!   :)   Houston... we have ignition.   8)
Title: Re: Mash temperature differences
Post by: bluesman on February 17, 2010, 05:22:57 PM
Absolutely a work of art!
Title: Re: Mash temperature differences
Post by: euge on February 17, 2010, 05:28:17 PM
OMG!

Beautiful. Fantastic craftmanship.

I must not be thinking enough about brewing.
Title: Re: Mash temperature differences
Post by: dhacker on February 17, 2010, 08:47:23 PM
Hey, thanks guys for the kind words.

Sad thing is that I'm almost done with the second generation version of "Hack's Whacked Orville and Wilbur Whirly Masher" based on a new Coleman 70qt. Extreme.  ::)  :-[
Title: Re: Mash temperature differences
Post by: a10t2 on February 17, 2010, 10:34:09 PM
That is the sexiest thing I have ever seen.
Title: Re: Mash temperature differences
Post by: dhacker on February 18, 2010, 12:05:45 AM
That is the sexiest thing I have ever seen.

The sexiest??   :o

You really should get out more! :D :D
Title: Re: Mash temperature differences
Post by: weazletoe on February 18, 2010, 01:49:24 AM
That is the sexiest thing I have ever seen.


No, THIS is the sexiest thing you've ever seen. Awesome tun BTW. What are you using for motors? I'm feeling inspired.

(http://i225.photobucket.com/albums/dd235/Weazletoe/S5001467.jpg)
Title: Re: Mash temperature differences
Post by: bspisak on February 18, 2010, 02:06:59 AM

Nice.  I was looking for an easy to make stir paddle and this just might be the ticket.  I didn't want to fab something like this (http://brewingtechniques.com/library/backissues/issue2.6/put.html) article shows, but I do like the idea of getting a toroidal movement of the mash.

How do those propellers do?  Do they create a slow toroidal type movement?  How does the finish hold up?  What motors are those?

Brian
Title: Re: Mash temperature differences
Post by: a10t2 on February 18, 2010, 02:26:51 AM
What just happened? I blacked out, and when I came to there were scratches all around my eyes.
Title: Re: Mash temperature differences
Post by: dhacker on February 18, 2010, 03:49:23 AM
No, THIS is the sexiest thing you've ever seen.
(http://i225.photobucket.com/albums/dd235/Weazletoe/S5001467.jpg)

I just bored my eyes out . . typing on a braile keyboard wearing my Ray Charles shades . . .  8)


Nice.  I was looking for an easy to make stir paddle and this just might be the ticket.  I didn't want to fab something like this (http://brewingtechniques.com/library/backissues/issue2.6/put.html) article shows, but I do like the idea of getting a toroidal movement of the mash. How do those do?  Do they create a slow toroidal type movement?  How does the finish hold up?  What motors are those?

Brian


Yes, the propellers do a very nice job of stirring. I'm not sure there is a lot of pulling from the bottom/ pushing to the top action, but never any dough balls and the entire grist is being moved in the water. I am using aluminum fan blades with an extreme pitch for the new tun so I can get better bottom to top action for step mashing with a heat transfer manifold inside the tun . .

Motors are from Herbach and Rademan
http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=TM93MTR2470&Category_Code=MTR (http://www.herbach.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=HAR&Product_Code=TM93MTR2470&Category_Code=MTR)
 
Title: Re: Mash temperature differences
Post by: stout_fan on February 22, 2010, 03:01:35 PM
Just be sure you close the lid before juicing the motors.
LOOK!
UP in the sky.
It's a bird...
It's a plane.........



NO, It's a flying mash tun!
Title: Re: Mash temperature differences
Post by: bspisak on February 23, 2010, 04:36:58 PM

Did you find a good source for those fan blades?
Title: Re: Mash temperature differences
Post by: blatz on February 23, 2010, 04:39:19 PM
ahhhh my eyes, my eyes...
Title: Re: Mash temperature differences
Post by: bluesman on February 23, 2010, 05:43:42 PM
What the hell was that. It's aliiiiivvveee!
Title: Re: Mash temperature differences
Post by: beersk on February 23, 2010, 07:29:17 PM
I wonder how the constant stirring affects efficiency...pretty neat idea though.
Title: Re: Mash temperature differences
Post by: Thirsty_Monk on February 23, 2010, 09:16:10 PM
Well commercial brewers use "rakes" to do stirring.
Title: Re: Mash temperature differences
Post by: denny on February 23, 2010, 10:04:33 PM
Well commercial brewers use "rakes" to do stirring.

This is one of those areas where I suspect there's a vast difference between what commercial brewers need to do and what homebrewers need to do.
Title: Re: Mash temperature differences
Post by: dhacker on February 23, 2010, 10:14:32 PM
Did you find a good source for those fan blades?

I just bought 'em from Tower Hobbies . . nothing esoteric about them.

http://www3.towerhobbies.com/cgi-bin/wti0878p?&N=P&P=1&B=TOPQ5075&E=ZINQ0500&L=PROP

Denny has asked me to do a write up on "Pimp" about my system. Since I'm in the middle of a major upgrade, I'll wait till I'm through, but that will explain all the whys and wherefores. A good part of it is that I'm an engineer who loves to tinker, and must have something to fiddle with!  ;D

As for efficiency?? . . don't know whether there is an improvement or not. I get about 75 to 78 percent with this tun. The main reason for all the doodads is to reduce heat loss during the mash.
Title: Re: Mash temperature differences
Post by: bluesman on February 24, 2010, 01:05:28 AM
I generally dough-in to the point (usually about 10 minutes) where I get random temperatures readings within a range of +/- 1 degree. For example, as I dough in for a target temp of 150 and I get between 149 and 151 at various locations around the tun I will put the lid on and set my timer.
Title: Re: Mash temperature differences
Post by: speed on February 24, 2010, 03:03:25 AM
instead of slowly stirring, i take my spoon in one end of the tun and make small rapid circles. it will move the grain across the whole length of the cooler. i feel that evens out the temps more.
Title: Re: Mash temperature differences
Post by: bspisak on February 24, 2010, 07:12:02 AM

I'm interested in a motorized mixer simply because I'm lazy. ;)

If you are doing multi-step decoctions, there's a whole lot of stirring to do. It takes at least 5 minutes of continous stirring to get temp gradients minimized (longer for stiff mashes.)

Also, Its hard to avoid aeration when using a spoon or paddle to stir with: one has to lift and fold the mash to evenly mix.

If you're using a direct fired tun, it's hard to keep the grain from scorching. A properly designed mixer can get the mash off the bottom of the tun.

An evenly heated mash can also help repeatability batch to batch.

Anyway, this article is a good read:

http://brewingtechniques.com/library/backissues/issue2.6/put.html
   
Title: Re: Mash temperature differences
Post by: stout_fan on February 24, 2010, 02:28:11 PM
... I get about 75 to 78 percent with this tun. ...

What you need to do is do a batch of a recipe that you know the efficiency of with the blades off and see if it makes a difference.
Title: Re: Mash temperature differences
Post by: beerocd on February 24, 2010, 02:43:06 PM
Stirring VS Recirculating? Is one better? I think the motors vs pumps and the effort required are probably equal. So does anyone see a definite benefit of one over the other?
Title: Re: Mash temperature differences
Post by: dhacker on February 24, 2010, 04:15:25 PM
Stirring VS Recirculating? Is one better? I think the motors vs pumps and the effort required are probably equal. So does anyone see a definite benefit of one over the other?

The breaking of any clumped dough balls is better handled by stirring . . .
Title: Re: Mash temperature differences
Post by: bspisak on February 25, 2010, 04:28:29 AM
Stirring VS Recirculating? Is one better? I think the motors vs pumps and the effort required are probably equal. So does anyone see a definite benefit of one over the other?

The biggest difference is that stirring alone doesn't allow you to adjust your mash temp. A recirc system usually runs through a heat exchanger. Stirring might in fact benefit a recirc system, though I would think if you have a good tun design, the grain is evenly rinsed by the recirc water, so it shouldn't be necessary.

My stirring setup will be used with a steam infusion system. I decided to go with steam after I saw a recirculation system in action. I wasn't impressed by the temperature fluctuations during recirc: The wort sitting in the plumbing cools when the mash is at temp (and it's not circulating), then the temp in the tun drops a few degrees when it kicks back in. Is that really an issue? Probably not, but add to that all the plumbing required and I decided to go a different direction.

With steam, I can get a pretty good temp rise, on the order of a couple of degrees a minute. Not sure what those RIMS/HERMS folks are getting, but from what I saw of the system I was on, it was much slower. Also, I wonder if those enzymes trapped in the plumbing aren't better off in the mash. For larger batch sizes, the amount of liquid in the plumbing is probably negligible. But, for 5 gallon stiff mashes?

Then there's cost: those pumps are expensive. You can get a windshield wiper motor to drive your mash mixer for $15. (But, I suppose if you've got a pump anyway....)  And you need two temp controllers and stainless fittings for your plumbing.

I dunno, it's probably more a philosophical debate than a technical one. Once you get any system dialed in, you can achieve great results.

Brian
Title: Re: Mash temperature differences
Post by: dhacker on February 25, 2010, 01:07:30 PM
Brian,

You and I are thinking alike . . keep the wort in the tun where it belongs during the mash! Hence my new tun with a heat exchange manifold inside the tun on the bottom. How are you generating your steam?
Title: Re: Mash temperature differences
Post by: bspisak on February 25, 2010, 10:47:06 PM
How are you generating your steam?

Nothing fancy: a cheap second hand presto pressure cooker. It's not too big, I believe it's a 5 qt model. I was concerned it might not be enough, but I fire it on my big burner and it works just fine. I recently did a mash that required 4 injections with steam (doughin to 120s to 140s to 150s to mashout) and it didn't need refilling. That was a 5 gallon mash.

I used soft 1/4" copper tubing to create a ring shaped manifold with perhaps a dozen 1/16" holes drilled in the top. That goes in the bottom of the tun and connects to a fitting I installed on the pressure cooker with a valve to turn the steam on or off. I didn't even bother with high temp tubing: just bought the only stuff the local HW store had that was rated to 170. I sometimes stays pinched once it cools from the lid closing on it, but I have always got it open and have used it a dozen times now without needing to replace it.

The only thing I need to change is that valve I use for controlling the steam. It gets really hot on top of the pressure cooker and is getting hard to open and close. It's probably not rated to those temps.

Overall, I'm quite happy with this setup. It let's me use a cooler to maintain mash temps and then inject steam to adjust or raise as needed. Even with a single step mash, I can now do a mash out and I haven't got a stuck sparge since. The cost and fab is a fraction of a recirc system as well.

Check out this article:

http://www.brewingtechniques.com/library/backissues/issue2.4/jones.html

Cheers!
Brian
Title: Re: Mash temperature differences
Post by: euge on February 26, 2010, 06:07:59 AM
Some dude on HBT converted a cornie for steam fired mashes. Very clever.

picasaweb.google.com/beermeister1/MashSteamBoiler# (http://picasaweb.google.com/beermeister1/MashSteamBoiler#)

http://www.homebrewtalk.com/f11/steam-injected-mash-system-18008/ (http://www.homebrewtalk.com/f11/steam-injected-mash-system-18008/)

This would be easy to do :

http://www.homebrewtalk.com/f51/easy-steam-infusion-mash-system-25974/

Title: Re: Mash temperature differences
Post by: dhacker on February 26, 2010, 12:59:21 PM
Thanks for those links, euge . . That is perfect!