Bolt substitution for rivets

[72tutone]

I known this has posted several times, however I'm having difficulty finding the right size 7/16-14 bolt length. I have read postings where I need to find a bolt with at least 1/4 shank on the bolt. Most of the bolts I'm finding have much more than that. My concern if the shank is too long I wont be able to snug the nylock but all the way down.
I have also read some are tapping the whole and just screwing the bolt into the frame.
Any thoughts would be appreciative.
These are frame reinforcement plates these would be going into.

[54belair]

I think Id use a grade 8--1" long ! No shank on the bolt and it should be plenty long enough for frame re-enforcement brackets. (might even get away using a 3/4" bolt.)

[54belair]

I think Id use a grade 8--1" long ! No shank on the bolt and it should be plenty long enough for frame re-enforcement brackets. (might even get away using a 3/4" bolt.)

[72tutone]

Thanks for the suggestion. But wouldn't u want a shank for the twist of the frame? I would think the shank would do good for that.

[72tutone]

Anyone else substitute rivets for just a threaded bolt without a shank?

[geezer#99]

Where are these frame plates and why are you using them? Factory or aftermarket addition?

[72tutone]

So looking at the pic, its the circular rivets. Also if you see the gap in between the reinforcement plate and the frame there was some rust built up. So I grinded down the rivets and resized them to a 7/16". However everything I have read says you want at least a 1/4" shank on the bolt so the shank fits in the hole. All the bolts I have found the shanks are much longer than 1/4". I have checked Lowe's, Home Depot, Grainger, and bolt depot.com and havent found a 7/16-14 7/16-20 with a 1/4 shank.
So at this point could I just tap the hole and fit a 1" 7/16 bolt with SAE washers on both sides and just get a nylock? Or does such a bolt exist?
Perhaps I'm being more paranoid over this than I should. However these also hold the spring plate to the frame, so I want to be sure the first time.

[steelhorse]

I wouldn't worry too much about not having a shank. I bolted a rearend and shackle brackets in a 74 Ford truck after an accident 20 years ago with grade 8 bolts and some Locktight and haven't had to touch them since.

[catch2otwo]

Id skip home depot type stores. Even grainger doesnt have much in terms of hardware. Contact your local Fastenal or even mcmaster carr. I would also try yelp for a local mom and pop fastener place, they are still around if you look hard enough.

[burnin oil]

Look around for a fastener store in your area. I am talking about a place that only deals in nuts and bolts. If they exist these guys will be able to get them. Sometimes you can buy a couple and other times you may end up with a 50lb box. Usually they sell by the pound. That said I wouldnt worry about the shank that much and concentrate on finding a snug fitting bolt that will work. The other option is to make your own bolt. Find one that is close to your needs and run a dye down it to thread the shank to your desired length. Just go slow and back the die up every 1/2 turn or so.

[72tutone]

Great ideas. Thanks all. Since I stepped them to a 7/16 size I think I will just tap it a with a 7/16 put some loctite on it, and some washers on both ends and a nylock nut.
Now I have a little better peace of mind with all this

[geezer#99]

Use a carriage bolt. Same round head as the rivets with a 1/4 inch tapered shank and snug them on with a lockwasher and a normal nut.
Here's an example.
http://www.usifaz.com/carriagebolts.html

[72tutone]

Thats a good thought. Now if I can find some in grade 8 that would suffice.