Beer Forum

tlael
A couple of questions about your mash tun. Do you use the reflectix on you mash tun while you apply heat? Also can you tell me more about where to measure your mash temps to avoid scorching or over shooting your temps. I have heard to measure your mash temp as it leaves the mash tun, especially in a direct fire set up.

Tasty
I like your mash tun design how do you go about maintaining mash temps or performing steps? If it is direct fire what steps do you take to avoid scorching or wild temp swings?

bhaas wrote:tlael
A couple of questions about your mash tun. Do you use the reflectix on you mash tun while you apply heat? Also can you tell me more about where to measure your mash temps to avoid scorching or over shooting your temps. I have heard to measure your mash temp as it leaves the mash tun, especially in a direct fire set up.

You got it. The reflectix is permanent so I have the mash burner down quite low to prevent melting/destroying it.
I would advise against bringing the strike water to temp in the mash tun. You'll have to apply too much heat and the keg vent holes around the lower skirt will allow that heat to crawl the sides and deform your reflectix. I bring my entire brew volume to temp in the HLT and pump it over to the MLT and apply a lil heat to gain back the few degrees that were lost during transfer.

As far as wort temp measurement, you're right, I measure it at the ball valve as it leaves the MLT. I recirculate constantly and have measured the return temp as well. It is usually a couple of degrees lower so I adjust my outlet temps to split the difference between outlet and return.

Step mashes can get a bit tricky, but once you figure out the setup you get used to it.
Basically, if the step is more than 5 degrees, I step 5 degrees at a time (resting a couple minutes between each step) until I reach the desired step.
Each little step only takes a couple minutes and I believe that prevents too much heat from being applied and scorching. So... It usually takes about 10-12 minutes for a 15 degree step.

bhaas wrote:Tasty
I like your mash tun design how do you go about maintaining mash temps or performing steps? If it is direct fire what steps do you take to avoid scorching or wild temp swings?

Like tlael, I'm direct fired, do a continuous recirc, and measure the mash temperature as it comes off the bottom the mashtun. Likewise, the burner under my mashtun is low BTU so I heat my strike water in the HLT.

I don't use any insulation around my mashtun. Heineken kegs are considerably thicker than most domestic kegs and it seems to hold the heat really well. I brew outside so the ambient temperature and wind speed matter. Even in extreme conditions, I'll only drop a degree every two minutes and it generally takes less than a minute to get back to temp.

I'm able to step mash without any scorching. A typical rise would be from 154F to 165F which takes about 15 minutes. I don't use a controller with calculus (PID controller) so I set the next temperature target a degree below the actual as the temperature will go past it about a degree on my system due to momentum.

Tasty

TastyMcD wrote:

Oktoberfest wrote:ok, that makes sense. Looks like lengthy debates on RIMS vs HERMS. Any recommendations on modding a keg? Things you would do differently. Things that worked or didn't work. Things that would have made the mash process much smoother. I only want to do this once and I've learned in the past to gather info 1st beforehand. Thanks for all your help guys.

I've posted this picture of my mashtun before on this forum. It's a modified Heineken keg. The unique thing is that it has a drain in the bottom. It's the only mashtun I've ever had and I've been using it about 14 years.
Tasty

Love this idea! How is the connection made at the keggle bottom? welded nipple, feed-thru....?