Answer: SAE J429 is a Society of Automotive Engineers specification for bolts covering “the mechanical and material requirements for inch-series steel bolts, screws, studs, sems1, and U-bolts used in automotive and related industries in sizes to 1-1/2 in inclusive.” From SAE J429 regarding studs:
“The term ‘stud’ as referred to herein applied to a cylindrical rod of moderate length threaded rod on either one or both ends or throughout its entire length. It does not apply to headed, collared, or similar products which are more closely characterized by requirements shown herein for bolts.”
So, a thread-each end rod or an all thread rod would be considered a stud by SAE J429. The specification goes on to discuss the grade marking requirements and states the studs need not be marked.
“Product Marking- Bolts and Screws- Internal drive screws of all sizes and other screws and bolts of sizes smaller than ¼ in need not be marked. All other screws and bolts of sizes 1/4 in and larger shall be marked permanently and clearly to identify the strength grade and the manufacturer. The grade identification symbols shall be as shown in Table 1. Markings shall be located on the top of the head and may be either raised or depressed. For hex head products, the markings may be indented on the side of the head. Studs need not be marked.
Marking product with special heads weaker than the threads and product manufactured with a collar shall be at the option of the manufacturer. The end user of product used for decorative purposes shall have the option of waiving the requirement for marking and its location.”
You can see more grade marking requirements for different products on our fastener identification markings page. Portland Bolt supplies many different nonstandard SAE bolts for a variety of projects. Please contact one of our team members today with further questions or if you would like a quote.
1 Sem: a screw and washer assembly