and another 1st time AGer

[ranger13]

OK I have done 9 extract brews now and this was my first AG brew. I am kinda a info nut which in the sport is good but can be bad. I have I a IPA that is want to do. 9lbs 2-row malt
13oz cystal 40
1.2oz EK Golding
1oz Williamette
1oz Cascade

I figured in thermal mass on my mash tun and came up with .15 . This would mean for a mash at 150F I would need a strick temp of 170.9 (171)F. So I go for it. Well after about 20 min in the Mash Tun my mash was still 163F, OK so I add some cold water and BAM 134F. OK thata not good so I add a little hot water(170) and the Mash temp droped to 128F then over the next 15-20 min it came to 151F where I wanted it. This makes no sence to me at all. But I got the mash temp right and let it go. Then Spraged at 170F for 1 hour and 22min. The brew is now in the fermenter and very thing looks and taste good. I got 76%EFF on the mash and was happy with that. The temp thing going up and down is what I was worried about. I have no clue what was going on there. All I can think of is I figuered my thermal mass of the mash tun wrong. O well all is good.

 

[zoebisch01]

Sounds to me like you are using a brew software that tries to adjust for your mashtun. The problem is this seems a little like black magic to me because in order to get a really accurate depiction of your tun you'd need to do it for each vessel individually. Without seeing the equation they use I am stabbing around in the dark to give you an answer as to why it went wrong....but can offer a suggestion (down below).

A few things that could be wacky. First off though I am assuming you are using a cooler as a mash tun? You must accurately measure your grain temperature. Did you do this?

Either way, I would suggest to take a look at Palmer's online guide under the section about strike temps etc and use those equations to see what strike water you come up with. Once you have that strike water temperature, go back to your brewing software and adjust the tun mass until you get the same strike temperature as the equations found on Palmer's site. This should (hopefully) give you the correct thermal mass to enter for your tun and (hopefully) appease the software. It is important to keep every other variable the same in this experiment.

 

[EdWort]

A few things that could be wacky. First off though I am assuming you are using a cooler as a mash tun? You must accurately measure your grain temperature. Did you do this?

This is a BIG ONE. I keep my grain in FoodSaver Bags in the garage and it's been pretty cool lately. I did not think about it and it cost me a few degrees in my mash temp yesterday. I had to add more hot water. I chalk it up to a learning experience. I never had this problem before because the grains were at room temp.

Next time, bring the grain inside a day or two before brew day.

 

[zoebisch01]

This is a BIG ONE. I keep my grain in FoodSaver Bags in the garage and it's been pretty cool lately. I did not think about it and it cost me a few degrees in my mash temp yesterday. I had to add more hot water. I chalk it up to a learning experience. I never had this problem before because the grains were at room temp.

Next time, bring the grain inside a day or two before brew day.

Ed, I would still measure it because I have found my grain temp even overnight in a bucket at room temp to still be consistently about 2-3 degrees below ambient temps (which may or may not be significant enough to put you too far from the target but it certainly won't help ). I am guessing because of the airspace in between the grains. The bigger the bag, the worst it will be probably.

 

[ranger13]

These are all great ideas and I will look into in alot more. No I did not take a temp of my grain, but next time I will. Again thats for the info and we will see what happens.

Thanks
Matt

 

[casebrew]

Ranger, if you use a rectangular cooler as a mash tun, add the hot water before the grains. That way the corners will get warmed up, not leaving so many hot or cold spots. Then mix,mix,mix before checking temp. My mashs got lots more consistant when I made that simple change.

But now my old rectangular cooler is getting lumpy and bumpy inside. I guess the 173 degree water is a bit too hot for the plastic, compared to 150 degree mash.

 

[ranger13]

I use a round cooler. I really think my mistake was in the Strike temp I refigured it and came up with 162F. That is 9 deg lower them what I came up with last time. I also did not take a temp of the grain before I started. I just used the room temp, I measured the gain sitting in the pantry and it was 3deg cooler then the room temp. Learning learning learning