TIM&JG ; fastener finishes

[Richard K.]

In the TIM&JG for 68-69 I've come across sentences like this: "It is held by a black-plated hex head bolt, split ring lock-washer, and large thick flat washer". Should it be assumed that the washers are also, black-plated, just as the bolt is? Are all "stacks" of fasteners plated with the same material? Are washers always zinc or cadmium plated?

Rich K.

[Gary B.]

Re: TIM&JG ; fastener finishes

When the sentence is worded that way, yes all are black-plated. Either black phosphate or black oxide.

Often, lock washers are a natural, dark finish from heat treating, and the flat washers are natural. We tried to identify those by stating that.

Gary Bosselman

[Gary B.]

Re: TIM&JG ; fastener finishes

...
Often, lock washers are a natural, dark finish from heat treating...

Gary Bosselman

Yes, it's pretty impressive how dark some lock washers can be from heat treating, e.g., the GM# 103328 lock washer used at bumper attachment locations from '65 thru years onward. They are similar in hue to Black Phosphate-treated parts. But they are not Bl-Phos treated. They are "natural", but heat treated to a relatively high hardness.

Gary