This will raise some rather different points of veiw
I just have a twin roller Mil ( or the Tony Mill ) and found that setting it at .9mm gives a fantastic crush with mostly intake whole husks and a good deal of flour. I also wet the grain the stop the husks breaking up.
It should be noted that you do need a reasonable amount of flour in the crush. Sometimes up to 30 %
I would agree that different grains need different setting on the mill. Just ask Tony when he crushed his Rye.
As far as I am concerned, I have got my mill set spot on for the grains and beers I make. And most mills would need to be set up different
I found this on the net. Some light reading.... B)
http://www.regional.org.au/au/abts/2001/w1/goldsmith.htm
In practical terms, the milling operation is designed to reduce the malt to particle sizes suitable for rapid extraction and enzymic digestion, maximum extract yield and throughput. However, maximum extract yield is achieved with a fine grind while maximum throughput is achieved with a coarse grind, thus the brewer needs to find a balance.
The objectives of milling are to:
1. Split the husk longitudinally, exposing and separating the endosperm, without tearing the hulls
2. Crush the endosperm allowing complete wetting and therefore rapid extraction and enzymic digestion.
3. Minimise the quantity of fine flour produced.
Therefore the ideal grist for wort filtration in a lauter tun would contain:
1. No intact kernels
2. The majority of husks split end to end with no endosperm attached
3. The endosperm reduced to a uniform small particle size, called grits
4. A minimum of fine flour.
When used in combination with lauter tuns, the majority of brewers use six roller dry mills, as shown in Figure 1. A fluted feed roller aligns the grain so they are presented in a lengthwise manner to the first pair of reduction rollers. The grain is split longitudinally and kept reasonably intact. The mixture is then separated through vibrating screens, with fine flour falling through to the grist case and small grits being screened to the third pair of rollers. Hard endosperms are separated from the husk in the second pair of rollers, along with coarse grits. The mixture is again separated through vibrating screens, with flour and husks falling to the grist case and remaining grits being delivered to the third pair of rollers.
For good lauter tun performance Briggs et al suggest that the grist should contain 15% husks, 23% coarse grits, 30% fine grits and 32% flour, while Kunze suggests that the grist should consist of 18% husk, 8% coarse grits, 56% fine grits and 18% flour. In fact, the optimum grist size distribution is dependent on a brewerys specific requirements for extract yield and throughput, the modification of the malt and the loading on the lauter tun.
