Seriously? The bolts are just too wimpy. I was experiencing some hum on my amp that would go away when touching the chassis, so i tightened the bolt a bit. (There are 3 ring terminals attached to it too). The hum decreased quite a bit. So i gave another half turn and it snapped right off. This is the second one on the same PT.
It is really frustrating as i have to melt the plastic insert in order to get it out. That is how i got the last one out. This one im still battling with....
I was doing with only 3 bolts but now 2 are gone on the same side so im going to have to get replacements wiyh no inserts.
You are not a big ape. Welcome to nuts bolts screws from China, India etc. They are all mixed up too from one batch to the next, no real way to know where these things are made. Can't blame MC as it's only to hold the lams together and the bells, and their supplier could be changing sources from one order to an other or buying through distribution. Could have been worse, could have been some bolts on catwalk or bridge or something. These things have failed from this and people have died.
Other possibility is that they were anti-magnetic aluminum and you did overdo it. Got a magnet?
