JB weld and/or Brownell's Steelbed epoxies work great for saws. They may be the same, I'm not sure. I've been using the Brownell's product for over 30 years for stock bedding and other related firearms repairs. I find that both are also great for fabricating broken off mounting tabs/ears on saws whether it be on a case, housing, tank or what ever. I reconstruct the broken part by first forming a re-enforcement structure out of stiff wire attached back to the the point where it has broken off. I then make a mold out of modeling clay for the outside form. I fill it with the epoxy and let it set well. Afterwords I do the final shaping and use Bondo for the final top coat if the epoxy did not finish out properly. If the ear/tab does not have a through hole, but has internal threads, I epoxy in the proper sized nut with the re-bar type structure I mentioned above. By the time I sand, paint and finish you really can't tell. It is time consuming but one heck of a lot cheaper than finding obsolete parts that are more often than not in as good of condition as the ones you already have, except for the broken ear/tabs. Then again, if your life is as boring as mine, you may welcome the opportunity to mess with this much like I do. I've never had one of these repairs fail to date. The key is the re-enforcement structure and it's contact back to the saw.