This is probably too easy, but here it is anyway. Most people looking at this car when it's done will assume it's all authentic. But the Model T cognoscenti will say (or think) "Aha! Not real Ford!" So here they are. Which is original, taken off a Model T, and which is modern and altered to resemble original? How can you tell?
The head looks thinner on #2.
Do I win a cookie?
The cotter pin hole on #2 is closer to the end and the threads go all the way to the head. Less chamfer on the head.
#4 definetely looks like Model T. #1 could be a Model T, but 2 & 3 look modern.
1,3 &4 are T Scott
I wouldn't use # 2 anywhere (Ford or not) that had sheer. The shank is non existent.
1 & 4 are T or of the time period of the T; the rest are not.
I think Dennis is onto something. -- The heads on the others are not pitted.
i vote 5, it does not have the bevel on the head like the other ones
I would give you all but #2 (claiming that #4 has spun in use).
However, your glass pix can be deceiving...and maybe you know more than we know at the same time?
Start with #1...are the head heights the same?
Why are #3 & #5 facing the other way? There appears to be a groove across the top (hmmmmmm)
If they are off the '15...not proof but a good test...Ford was still using what would have been rated a #2 Gr. bolt under the future SAE system, so look up the hardness for a Gr. 2...and then use a hardness file on it....oh wait, hardness files might not be available in farm/estate finds...
Cotter pin hole in #2 is not champhered and several other flaws already mentioned.
I think 1 and 4 are the real deal.
All of them except #2 have thick heads. I think any of them could be T-era, pitted or not.
If I'm not right; I'm gonna "bolt " off this posting. :-)
Congratulations to all who spotted #2 as the modern bolt. The most obvious giveaway is the shorter head. The heads on T bolts are 5.", while the new ones are .375".
George noticed the grooves on top of #3 and #5, and I wonder about those. They're not deep enough or wide enough to be screwdriver slots. They're also slightly off center. Can anyone tell what those are for?
At first I thought the grooves might be grade markings, but all the grade markings I've seen on bolt heads are raised features, not grooves.
In any case, I'm including the attached pic of grade markings and their meanings for general info.
Looks like the grooves are roughly in line with the cotter pin holes. They were probably a guide to help align the nut slots with the holes in tight areas.
RV has it. I put light file marks on the top of my "hard to see bolts" for the same reason.
#4. Has the most rust pits.