I belong to the local Eagles club and it has been up to me to keep the popcorn machine working. Recently the flat bottom bowl in which the popcorn pops fell out of the bowl housing. This is because there is a disc welded in 4 places to the outside bottom of the bowl and the welds all failed. There several 8-32 PEM studs coming out of the disc. Over three of the studs fits a steel plate which clamps the heating element against the bottom of the bowl. Two of these three studs penetrate the housing and nuts are threaded on to these studs to hold the bowl into the housing. So I had to re-weld the disc back into place. Anyway, all the welds failed by cracking through the centerline of the beads. So what could have caused these cracks? Could it be the heat cycling? Or just bad welds? When I re-welded the disc I made welds larger in cross section than the original welds but I don't know if the larger welds will be more resistant to cracking. Any thoughts? The original welds did last for many years so if my welds are at least as good as the original I will probably never need to do this repair again. On the other hand if there is something I don't understand about how the stresses are affecting the weld maybe my repair will fail in a short time. Any thoughts? Thanks, Eric
- posted
10 years ago