Excise duty on lenses fitting in frames

Excise duty is leviable on manufacturing. And manufacturing is a process in which a product has come into existence with new name and new usage. 

Here in this case vendor is only giving service as per customer specification. Fitting of lens into frame dont satisty usage test there there is no change in use of frame .his prime business is to sell frames . so i guess excise should not be levaible . service tax comes into picture .