Screws

[jackellis]

I'm installing some heavy-duty shelf standards in the garage. They need flat head #10 screws to hold properly. I used a high-strength screw sold under the brand name Spax for material shelves in the shop but I've only been able to find these at Orchard Supply and they don't have stores near Tahoe. McFeeley's sells them but I don't need enough fasteners to make a mail order worthwhile (at least not now).

I know better than to use drywall screws and deck screws are also probably not suitable. What about coated "exterior" screws - will they have enough strength? Lag bolts won't work - the bolt head will interfere with the shelf bracket.

I just tried a #10 wood screw from Lowes and the shank broke, so they're clearly not strong enough (drove over 100 Spax screws and none of them broke).

[crokett]

What about #10 ring shank nails? Nails have more shear strength than screws. They will pull out a little sooner than screws but the load on a shelf standard is all shear I would think. Otherwise I think the #10 exterior screws would work just fine.

[cabinetman]

IMO, coarse thread screws will hold better than tapered wood screws. If all you can find are exterior deck screws, drive them slow, and just bump them tight. Spinning them down until tight gets them hot, and more likely to have breakage.
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[jackellis]

First, thanks for the suggestions. My wife is going to rescue us by picking up a package of Spax screws on her way back here.

They will pull out a little sooner than screws but the load on a shelf standard is all shear I would think.

You'd think so but a little experiment appears to show otherwise. I have some light duty standards for a closet in my office. If I push down on the free end of a bracket inserted in the standard, the standard bends and that bending moment will pull an inadequate fastener out of the wall. This happened in a walk-in closet in our Bay Area home. A hanger bracket that the clothes rod sits in is slowly pulling out of the wall due to the effects of the bending moment.

Heavy-duty standards won't bend as much, but the moment is still there.

[LCHIEN]

First, thanks for the suggestions. My wife is going to rescue us by picking up a package of Spax screws on her way back here.



You'd think so but a little experiment appears to show otherwise. I have some light duty standards for a closet in my office. If I push down on the free end of a bracket inserted in the standard, the standard bends and that bending moment will pull an inadequate fastener out of the wall. This happened in a walk-in closet in our Bay Area home. A hanger bracket that the clothes rod sits in is slowly pulling out of the wall due to the effects of the bending moment.

Heavy-duty standards won't bend as much, but the moment is still there.

I agree, that's entirely true, shelf brackets will cantilever the load on the screws so they will tend to pull straight out, not just shear load. Especially the screws at the top of the standard.