Official Luthiers Forum!

No...the shear load is more or less perfectly opposed when the rod is restrained inside the channel. Therefore, technically the weld should be stronger when the rod is isolated in the channel. When the rod is tested outside the channel the load works, to some extent, to peel the weld apart rather than to have the load applied in a perfect opposing force. In this way, a small stress crack can begin in the weld without fully breaking the weld, only later to have the weld break, after the rod in installed in a neck and pressure is applied.

I feel that a company that places the burden of testing on their customers, and then doesn't fully grasp the implication of that test....well...they aren't doing it right.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Thanks for the interesting pics. Yep, very little penetration. They did at least use rod on this one, but still no bevel. The main problem I see is that the puddle is almost all on the rectangular bar, barely touching the threaded block. The failure is in the base metal of the block (the heat-affected zone, and also the melted base metal doesn't get the rod's de-oxidizers, so it's less ductile). If they consistently put the puddle on the bar, the welder is probably trying to avoid distorting the threads of the block, so they can save or minimize the usual step of re-tapping it (not a good bargain). It also looks like an entirely brittle failure -- I wonder if the block is made from a free-machining steel (1144, 12L14), which is nice for making threads but not for welding.

It's not hard to see why the Blanchard rods are silver soldered: far more surface area with little risk of distortion. They are pricey (brass and stainless), but silver soldering that small joint would not be expensive.

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David Malicky