70' k/20 first restoration help

[WIDESIDE72]

Originally Posted by swamp rat

I have seen builds here where none of the cross members are removed, and i have seen where all the rivets are removed and all the pieces individually sand blasted and repainted, If you do remove cross members you need to be using Grade 8 hardware to bolt it all back together, i have had little luck finding loc nuts stronger than Grade 5 but they may be out there somewhere.

The grade rating is in reference to the shear force required to break the bolt. A nit is pretty much a nut. Thatis why there is no different stampings (or any stamping at all) on a nut like there is on a bolt.

[WIDESIDE72]

Interesting reading. They say not to substitute nuts and bolts of different grade but no mention of nut grades.

http://smallengineinformation.com/?page_id=508

[WIDESIDE72]

I stand corrected! There are nut grade marks! According to the youtube video search for video "determining nut grades", cant figure out how to post link), grade two have no marks, grade 5 have two marks far apart, grade 8 are closer together.

Personally I have never seen a failure due ro the nut. Then again i am not a structural engineer!

[swamp rat]

Originally Posted by WIDESIDE72

I stand corrected! There are nut grade marks! According to the youtube video search for video "determining nut grades", cant figure out how to post link), grade two have no marks, grade 5 have two marks far apart, grade 8 are closer together.

Personally I have never seen a failure due ro the nut. Then again i am not a structural engineer!

If you go look in a hardware store that carries grade 8 and grade 5 hardware you will quickly notice that grade 8 is also coated differently than grade 5, i cant remember what the coatings are but its a yellowish green kinda gold color. You will also find grade 8 nuts and washers and loc washers in the same area as the grade 8 bolts, you don't want to mix them if you need grade 8.

Here's a picture of a 5/8 grade 8 nut showing the two marks, there is also another mark on the opposite side.

Grade 5 and 2 are a silver colored finish.

I have not seen anyone use less than grade 8 hardware when assembling a frame, i know i wouldn't.

[Skid99]

ill just leave the rivets in!! lol

[litew8]

Originally Posted by swamp rat

If you go look in a hardware store that carries grade 8 and grade 5 hardware you will quickly notice that grade 8 is also coated differently than grade 5, i cant remember what the coatings are but its a yellowish green kinda gold color.

It's Zinc Yellow-Chromate plated finish your looking to say. I don't think it has anything to do with the grade strength. Just corrosion protection.

[swamp rat]

Originally Posted by litew8

It's Zinc Yellow-Chromate plated finish your looking to say. I don't think it has anything to do with the grade strength. Just corrosion protection.

I agree, its just a plating, but it makes them easy to identify.

[litew8]

True. I replied to this thread because I was just at the store the other day buying these for my truck.