JB Weld or Plastic Steel will work. I have used it many times, and
you can thin it following the instructions for the clean-up solvent
listed on the package. But JB Weld works at the regular mixing
consistency, for me. You might also check with Kerr Wax…they make
MANY kinds of wax, some rather high temperature, you might be
surprised. Also, do not fsail to check the many, many types of
adhesives and fillers made by Loctite (www.loctite.com). They have
gap filling adhesives that with stand 450 degrees F and boiling in
nitric acid for extended periods, and many exceed the shear strength
of aluminum. Amazing products.
Wayne Emery
Jewelry Design Studio
“Jewelry Photography Made Easy”