i have been mixing my own nitro for some months. but its not as easy 8 oz of one and 8 oz of the other does NOT =50%. thats because of the size of the molecules. a hydrometer is the only way to know what % you have. cause the fuel you are starting out with is mostly methanol, get a plastic jar from the store, dole has 24 oz jars with oranges ect. the top bulge is 18 oz. then find a scale weight it, then calculate 15% add that much methanol. this will NOT be real accurate, but should be close. please dont jump on me about it not being accurate, i know is not. just be careful. NOTE: a methanol fire can not be seen in day light, but water will put the fire out.