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Old 09-12-2017, 08:03 PM
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Dead Man Dead Man is offline
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Join Date: Apr 2014
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Are you concerned with the screws pulling out, or something?

I'd put $100 on 4 faceplate screws having higher pullout strength than any part of the stem's sheer strength.

Screws are strong, with regard to shank direction loads.

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In alpine climbing, we have objects called "ice screws," used for intermediate protection whilst "lead climbing," and for building belay anchors and stuff. Tests have shown that ice screws driven into an ice wall at a 10-15% upward angle from vertical plane offers the highest strength, despite traditional/common misbelief that driving them into the wall at a slight DOWNward angle would offer the best "strength." but ice sheers very easily - its strength, and subsequently the ice screw's strength, rests on pullout. NOT sheer. Like brittle, porous metals...... like cast aluminum.

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and I know from construction that you have two kinds of simple (non mechanical) fasteners - nails, which offer sheer strength; and screws, which offer pullout strength. Use nails when forces are sheer, use screws when forces are perpendicular to the mounting surface. You CANNOT use screws for things like sheerwall, roof decking, deck decking, hurricane ties, joist/perlon hangers, etc, etc, etc. They will just straight up break if you try to hold sheer stress with them. Likewise.... 12 or 16D coated nails have great sheer strength, but you'll never use them for expansion load fastening.
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