Beware of Chinese made wood screws

[wil]

Following the directions in Canoecraft, we bought some #6 1 1/4" roundhead woodscrews to attach the outer stems to our Prospector canoe.

I predrilled the stems, both inner and outer, full length, for the screws. Six of the sixteen I screwed in snapped at the bottom of the shank where the threads start. The screws were waxed and driven in a a medium/ slow speed and did not bottom out.

We were lucky that all but two broke off below the surface and the holes could be plugged by a dowel.

I did a QC test on the remaining screws and 2/3 broke. The hardness and stregenth of the screws varried wildly. Simple answer, don't buy Chinese screws from Home Depot. Buy Canadian or American made if possible.

wil

[Glen Smith]

Sorry to hear about your mis-adventure with wood screws. The bad news is that more and more Canadian and American companies are now importing Chinese hardware and selling them under their own label name. The way things are going, we are going to end up having to build a complete canoe just to test all the material that we want to use to build the final product.

[ealger]

Wil, sorry to hear about your experience with breaking wood screws.

For future reference, McFeely's offers a "flat top pan head pocket hole screw" I like for holding the outer stem while the epoxy sets up. I use their 6 x 1-1/4" pn 0612-PTC along with a flat washer under the head.

Mark a center line down the inside of the outer stem. Mark out the spacing for screws as desired and drill a hole through the outer stem from the inside just large enough to pass a screw. (A drll press is handy here.) Set the outer stem in place on the inner stem and lightly center punch the inner stem using one of the screws. Remove the outer stem and make sure that the marked spots are in the center of the inner stem!

Reinstall the outer stem and drill pilot holes for effect. Don't drill through the inner stem!

These screws are square drive and should be tighten just enough, by hand, to pull the stem down but not so tight as to squeeze out the thickened epoxy.

When the epoxy has cured, remove the screws, drill out for a 3/16" dowel, 1/4" deep or so and plug up.
Ed..

[alick burt]

Even the best brass screws can break when put into hardwood.One method I often use to avoid breaking brass screws when putting them into hardwood is to put steel ones of the same size in the hole first.That way the hole is cut by the stronger screw and you can then put your final screws in place without breaking them even if they are nasty cheap ones!
A bit of soap or wax to lubricate them also helps.
Regards
Alick