I haven't figured out the Dapple Blend recipede yet, but I will help what little I can. I do know that you mix two grains into a grain blend, and can then mix in a third grain of your choice.
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First, you must have the grain on hand. You can grow and harvest your own, or buy it from other stables in the HEE store. I recommend getting the grain itself, so that you can see the percentage (%) of fat fiber and protein of each type of grain in a handy little chart.
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You can use the mixing station to mix two grains together to see the percentage without actually using up your grain yet. Make sure you hit the Caculate button, not the Mix Grain button. You can only mix or calculate up to the amount of grain you actually have on hand. I tried, but you cannot mix together two smaller blends to create a larger amount of the same blend.
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I'm not certain this is the right method, but I would guess that you can take the ideal blend, subract one (out of the 8 grain options) grain's percentages for protein fat and fiber, then use that as the target goal to attempt to reach with the blend calculated via the grain calculator.
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Visual representation of the math idea (if it works):
Ideal Dapple blend grain - one grain's % = target grain % to reach via the grain mixing station
12% Protein ideal - Grain 3 (such as corn's % protein) = % Protein goal
3% Fat ideal - Grain 3 (such as corn's % fat) = % Fat goal
12% Fiber ideal - Grain 3 (such as corn's % fiber) = % Fiber goal
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Then (if it works):
% goal + (premade grain blend) = eventually ideal % for Dapple Blend recipede
% Protein goal = (Grain 1+2)
% Fat goal = (Grain 1+2)
% Fiber goal = (Grain 1+2)
(You will have to actually use up grain on hand to create a grain blend to proceed with the next step, please don't mix too small a quantity)
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So that (if it works):
Grain blend (Grain 1+2) + Grain 3 = % Ideal for Dapple Blend recipe
Grain blend + Grain 3 = 12% Protein Ideal
Grain blend + Grain 3 = 3% Fat Ideal
Grain blend + Grain 3 = 12% Fiber Ideal
(to eventually create the elusive Dapple Blend recipede)
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