What causes backing plate failure

[Caymandave]

I was using the Groits Garage 3” tool with 5000 grit sand paper. Plenty of soap and water for lube. Thing just came apart too hot to touch. I realise heat is what caused the failure but there was not much drag with 5000 grit sand paper considering I was using water and soap and keeping things wet.

 

[WristyManchego]

Heat, forces and age.

Take your pick. Two are caused by technique, the other can’t be avoided.

 

[Paul A.]

I have found torque and excessive heat. I have ripped out quite a few and know it was certainly my fault every time. It happens. I now keep several of each kind in my inventory.

I know I exert a little too much pressure when trying to coax a little more cut out of a compound every now and then and because of age, it might tear a bit inside. Even though you say you weren't using much pressure it may have had a fatique failure inside a bit.

I have now adjusted my technique to machine weight ONLY for ALL passes. I let those abrasives and pads work to do what they were intended to do. They don't need any
coaxing by me.

What was the brand of BP?