sourcing aluminum carriage bolts and knurled nuts

[nolanola]

I'm trying to price out a bid for a municipal traffic sign job, and they have very specifc requirements for what kinds of nuts and bolts can be used. I'm having trouble finding where to get them, especially the aluminum knurled nuts.
The description in the bid is written" ...shall be required to use 5/16" x 2" tamper-resistant aluminum carriage bolts and knurled nuts. Bolts and nuts shall be American Standard B18-5 2024-T4 alloy."
please and thanks, Ricki

 

[MikePro]

are the knurled nuts supposed to be tamper-resistant too?
i know that there's "trident" security nuts that you can use with carriage bolts but if I had to "tamper-resist" a knurled nut, then I feel like I'd have to drill&tap a security set screw into the side of it.

 

[JBurton]

Vulcan Signs - Fasteners

 

[Johnny Best]

Never heard of aluminum carriage bolts. Steel, galvanized, and stainless steel.
I would think aluminum would bend and be weak.

 

[pro-UP]

If you have time, submit an RFI. If they have that specific of a requirement, they should be able to provide the supplier / resource. Good luck on your bid!

 

[JBurton]

Never heard of aluminum carriage bolts. Steel, galvanized, and stainless steel.
I would think aluminum would bend and be weak.

Me too, but then again it's just clamping power that these are supplying. I wonder if it's easier to make vandal resistant parts from aluminum, or if they are going for an all aluminum build, so no rust. Likely it's to prevent rust running down the faces.

 

[Johnny Best]

If they are in New Orleans close to the guld then stainless is the way to go but I have seen aluminum break down from salt air and stainless rust over time.