Bolt Identities

[Curtis]

I'm getting hardware ready to go off to the plater. I managed to bag and identify some stuff when I took the car apart. I also at one time bought a bunch of miscellaneous hardware that had been taken off cars.

So my two cars seem to have the 1/4-28 bolt for the fenders, door hinges, center console and a couple other places as shown in the photo with the "dp" marking on the head. I also have a bunch of the same exact size bolt with a "T" marking.

My question is if anyone has noticed in restoring their car is this maybe Datsun just using different suppliers at times? I'm not finding any of the T marked bolts on my driver.

IMG_2433.JPG

[goldbug]

I had noticed a number of the "T" bolts on my car (I've catalogued a large percentage of the fasteners as I deconstructed my car), but didn't really notice many "dp" bolts--but many were too corroded and/or had many layers of paint on top.

[Linusrp]

Curtis,
I re-threaded and re-plated quite a few bolts off a couple of model year cars. I have both the "dp" and the "T" marked bolts. Just checked my '67' though, the door hinges and center console are all "dp". Not sure if that helps.

[Curtis]

Curtis,
I re-threaded and re-plated quite a few bolts off a couple of model year cars. I have both the "dp" and the "T" marked bolts. Just checked my '67' though, the door hinges and center console are all "dp". Not sure if that helps.

Thanks.

I texted with Ross today and the T seems to be more abundant. These cars I have are all dp so far. And of course there are the many other various markings on the 5/16 and 3/8 bolts. The triangle occurs a lot. Bolts that are used where higher strength is needed have letters and numbers on them.

As I commented to Ross this seems to be a case of the farming out stuff so everyone works. What the Japanese think of as the iron rice bowl.

[dynaguy]

The markings you are speaking about are not grade marks, but are foundry identification markings. These are to show the manufacturer of the fastener. For a car that is to be driven, it is best to replace all graded fasteners with new, certified ones. The metal fatigue from age and use, along with what introducing high heat in the plating process to a graded bolt can create hydrogen enbrittlement and lead to failure. FWIW Pat

[Curtis]

The markings you are speaking about are not grade marks, but are foundry identification markings. These are to show the manufacturer of the fastener. For a car that is to be driven, it is best to replace all graded fasteners with new, certified ones. The metal fatigue from age and use, along with what introducing high heat in the plating process to a graded bolt can create hydrogen enbrittlement and lead to failure. FWIW Pat

Yes, all critical bolts have been replaced. Not taking any chances on the frame and suspension. These bolts are just the fluffy stuff.

[mraitch]

When Roadsters are accepted to Pebble - THEN worry - 'g'

[ehanson]

When Roadsters are accepted to Pebble - THEN worry - 'g'

So Soon..