I'm pretty sure these are grade 8 bolts, they have these markings on them that I've never seen. And the head of the bolt is "dished" slightly, maybe 1/16" deep. They were holding the leaf springs to the axle on the front of my 33. I'm positive they aren't original, but I've never seen this marking before, kinda neat! I also found a few smaller bolts on the engine that have these markings. Every single bolt on the truck is grade 8 (but with the usual grade 8 markings), so I'm guessing these are grade 8 as well Anyone know what it means, or seen it before? If nobody knows, I'm just going to assume they are alien hardware from a space ship. .
I used them too. They were sold to me as grade 8’s even tho they not have the typical marking of an 8.
Grade 8 bolt has the 6 radial lines and these have VI on them.....so maybe a grade 8 bolt manufactured in Rome?
https://www.electronicfasteners.com...09/northamericanmfgidentificationmarkings.pdf Try this, 22 pages worth, or this one: http://idot.illinois.gov/Assets/upl...erials/Metals/fasteneridentificationguide.pdf 165 pages...
Thats Interesting. Has to be for specific industry or spec. The hash marks we are used to seeing or refer to are SAE spec. ASTM, Aircraft, Structural(steel), are other specs that have specific bolt markings. Could be manufacturer specific, look at Caterpillar bolts, most are branded. Maybe its a NASA or government bolt, that could be an $8000 bolt that went to surplus.
haha! I'm gonna go with NASA, that sounds cool I'm definitely keeping these. I have a small bin that I keep interesting hardware in.
I just went through both of those documents, didn't see anything that looked close to this. I'm guessing these are probably some cheap imports? I hope not, because they look neat
I'd say an...offshore manufacturer somewhere. Do they "ring" like a GOOD quality fastener, or do they "thud" like lower grade fasteners when slapped with another piece of metal ? Mike
Keep in mind that Grade 8 refers to the tensile strength of the material. You also need to know the fracture toughness of the material after heat treating. Most off-shore bolts are low quality steel, heat treated to a high tensile strength. Do not use them in applications that can kill you when they fail!!
I've wasted a bit too much time searching and the insignia doesn't seem to be currently registered. https://www.uspto.gov/sites/default/files/documents/FQA_Registry_2.pdf Normally gold anodized bolts aren't "Cheap low grade foreign bolts" They are usually grade 8 or above. I'm thinking that those bolts are either private label similar to the Cat Equipment bolts that have/had their distinctive design on them. Other thoughts: Manufacture did a logo/trademark upgrade/change. Manufacture got bought out and the new owner changed logos. Manufacture closed their doors but there are still bolts they made floating around.
The newest then can be is 15-20 years old, so that's definitely a possibility that company isn't around anymore, or has changed markings. They don't SEEM like cheap bolts to me, but honestly, I really wouldn't know how to tell. They make the same sound as grade 8 bolts I get from McMaster, and seem to have good finish and similar hardness. These bolts heads were 4-6 inches off the ground exposed on the front axle, and the finish seems to have held up nicely.
I've had to look up some head markings for work and was amazed how regulated they were. You can't run and you can't hide. I used the resource to identify some stainless bolts at Ace Hardware which turned out to be an A286 alloy.
The Jalopy Journal
