Thermal Mass of Mash Tun

[adm]

I'm playing around with Beer Alchemy and one of the items in the Mash Calculator is the Thermal Mass of the Mash Tun (in Kg)......so, How do you work this out?

If it helps, I'm using an H&G coolbox mash tun....

[steve_flack]

Empirically. You basically bugger about with it using a set of known values from a previous batch (strike temp, mash temp, grain weight and liquor volume) until the numbers come out right.

Essentially it's a fiddle factor.

[adm]

Ah. Thanks!

So.....given my last brew was 5.7kg grist, 13.1 litres of water, 21C room temp and hit a 66C mash temp spot on from a 73C strike temp.....that means the Thermal mass is....type, type, scratch head, type.....ummm....200g!

Seems like a small number, but then again I use it preheated, and it's a pretty good insulator.

[Gurgeh]

I took steve's advice and it worked for me

alternatively, you could overheat your strike water by a couple of degrees, chuck it in your mash tun and wait until your strike temp is achieved. this will zero that 'fiddle factor'.

[steve_flack]

Seems like a small number, but then again I use it preheated, and it's a pretty good insulator.

Preheating makes the number rather small.

[adm]

I took steve's advice and it worked for me

alternatively, you could overheat your strike water by a couple of degrees, chuck it in your mash tun and wait until your strike temp is achieved. this will zero that 'fiddle factor'.

I've done that too! Although waiting around for the temp to drop is frustrating when I'm trying to shorten the brew time. although.....Doh!...I suppose I could just add some cold water if required.

As I say though, the last brew I hit it smack on....so maybe i've got it dialled in now. I'll do a few more to test....

[Gurgeh]

I'll do a few more to test....

I think you'd better...