The mold repair continues . . .
I've finished all of the structural repairs and struggle with repairing details as well as the overall quality of the surface of the molds. The molds wil not have as nice of details as the originals, I've accepted that, but neither will this set of molds ever be used to make more than this one set of final parts. If I ever want to cast, I'll be better off to do a new set of molds anyway as I know the final parts will still need altering to mate properly with the metal receiver. Yup, that means big work will be required on the pieces I pull from the molds, but that will take less time than restoring every detail into temporary molds.
This work sucks, so I took some time to look ahead to a different part of the project--metal work! All avenues of CNC of manual milling have been exhausted, so I'll be cutting, routing, and stick welding to make the lower receiver happen. Here are the aluminum pieces I'll salvaged and purchased to start on the lower receiver posed next to my Pep lower receiver (that by now has seen better days). Not shown is a long section of 1 1/4 inch square channel that will be cut in half to make the bottom of the receiver between the two halves.
This will be a tricky job welding different thicknesses and grades of aluminum. Unlike wire welding, the heat is not localized, and making welds that penetrate into the surface on the metal parts is very hard--anything less is just soldering, i.e., non-structural. I'll get in and explain more when I get started making these parts. For now, this is just a teaser of what I'll be doing. Final, non-structural, details will be grafted onto the surface with JB Weld as it is about the only adhesive sure to hold as well as tolerate the coating process.Redshirt