Watch out for Chinese Bolts

[Phil Waterman]

Be careful of where you purchase hardware. Check the box and check the hardware for markings. Just bought boxes of 5/16ths bolts, nuts, washers and lock washers at the local hardware store. All of them marked grade 5. I’m reassembling the Pattern 12 sheet metal and was loose fitting all of the bits. When I went back with the air-ratchet, air pressure set at about 40 PSI, started tightening bolts down and breaking them off. Now I could see breaking 5/16 and 3/8 s if I was using the impact driver turned all the way up but air-ratchets just don’t put out that much torque.

Then went back and checked some 3/8ths nuts removing them to check the treads I discovered that the bottoms of the nuts are mushroomed out. Also found that the threads on some of the bolts had been flatten going through two layers of sheet metal.

Buying the hardware there was just convenient because it was on the way back from the gym. Now I got to figure out which bolts came from where and check the markings.

Guess I’m back to buying grade 8 bolts by the pound from the local tractor dealer $4.30 a pound what ever size. I had been using grade 8s for all the chassis now I’ll use them for everything.