shipping based on tax class

[gardenho]

I am wondering if it is possible to design a shipping module that ships based on tax class? If your wondering why it is because the items that I would like to ship free are tax exempt, everything else shipping charges apply. We ship around the world with the price of shipping based on total order amount, and I am already using 8 different modules to accomplish shipping for all with regular and express options for all other countries plus zones within USA and Canada. It's taken me almost a week to get them all figured out and working exactly as I wanted including to charge no shipping on the items that are shipped free if they are in the cart with other items but the free shipping items on their own (gift certificates and our paper catalog) are still a problem. I have looked at each and every shipping module contrib and none can work for this purpose for one reason or another. I figured a module that limits itself to only items that ship by tax class might be the simplest solution - but I could be wrong and probably am.

 

It is a heavy modded shop, with over 30 contribs and modules changed/added - and they all work (I'm rather proud of that!) There are contribs out there that will accomplish what I'm after like download controller but they involve more mods and I am leary of 'going there' because I already know I'll run into problems matching code on any of the main pages that are called up.