Stock Management and Profit

Morning all

A bit of a long one so please bear with me...

Having used Quickbooks for a couple of months now I am questioning if it is the right system for me, or in fact is there any system that will do what I need. Perhaps with a better understanding of how to use Quickbooks I can make it suit and provide the information I need. 

My issue and lack of understanding revolves around the following situation:

My business is selling Industrial Coatings. Each product is made up of a Binder and a Tint and these together in different formulations produce a finished coloured coating.  I have Binders and Tints as stock items on my system. Once the tint is added to the binder I sell this as a mixed colour using a separate product code on the system. However each time I make a mixed colour I don't use all of the Binder and Tints so they could last for months. My problem is how is this shown on my records. My original purchase of the Binder and tints  continue to show as complete in stock holding even though I may have used a certain percentage of each. The valuation for these is also shown at full value. 

I know what the mixed colour price is (this varies each time depending on the formulation) and I add it each time that the product is sold so the margin on this is accurate. But how can I write down the Binders and Tints off stock without these showing at a loss as these as individual products are not sold but are used to make a completed mixed colour product.

Difficult to understand I appreciate, but I would be grateful for any guidance. 

Do I need to set up the codes differently? 

Thanks

Paul