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Topic Date User

SS Coachscrews at Bunnings - Are they ok? 31-Jul-2014 At 8:22:11 PM patto

Message

On 31/07/2014 E. Wells wrote:
>Hey Mikl you just mentioned the 30mm thing. What is that about, I clip
>alot of GIMB's with full thread , think all of em on sweet dreams , some
>at Zig Zag , abseil anchors at narrow neck , and some of my very own...I
>know its not ideal , Im just wondering why not.

Having thread exposed reduces the cross sectional area of the portion of the bolt subject to maximum shear/tension.

With reduced cross sectional area you get less strength. (33% less for course thread M10 bolts!) Of course if all other things are good then you still have plenty of strength in the bolt. (A quick back of the envelope calculations would suggest A50 is good for 39kN of simple shear.)