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Topic Date User

SS Coachscrews at Bunnings - Are they ok? 29-Jul-2014 At 11:37:46 AM nmonteith

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On 29/07/2014 The good Dr wrote:
>The el cheapo Bunnings (or other) SS Coach bolts, if they have A2 on them,
>may be grade A2-50. These have approx 30% less capacity than A2-70 grade
>and are considerably more maleable, ie the metal stretches more easily.
>A2-50 elongates 50% more than A2-70 (regular strength for fixings). This
>may explain why the heads can be snapped off far more easily.

Do they warp visibly before breaking? I have snapped a lot of carrots off when rebolting - most of the time you can twist the head about 90 degrees before it snaps. This obviously never happens in a climbing fall. I've done pull out tests (using Mikls bolt tester) with these SS coachscrews and saw no sign of bolt damage. The rock or glue failed way before any bolt warping at well over a tonne.

>Neil, I thought you were not placing glued in carrots any more.

As I said above - I have been using them mostly with Fixed Hangers, but I have placed a few as top belay anchors at Point Perp that require keyhole hangers (as is the usual practice at that cliff to hide belay bolts from tourists)