The welding repair or implementation of engineering changes on larger molds and dies can be accomplished by standard or microscopic GTAW or TIG welding. Surprisingly small weld metal deposits can be applied on very large blocks, with the help of microscopes when the appropriate care, skill and equipment are used.   

Larger repairs are accomplished by patiently welding layer upon layer on top of layers with filler rod until the required final dimensions are reached.  Very heavy or extra large area build-ups are conventionally GTAW welded but may even require the use of GMAW (MIG) or SMAW (Stick) welding, especially when applying hardfacing or wear and chemical resistant filler materials. 

     Repair of scratches in a P-20 "Fire Helmet" thremoset cavity block using an overhead microscope and .010" wire.