Sunday, January 18, 2015

Christmas Tree Stand Clamp Screw Thread Marginality


How's that for a blog post title -- "Christmas Tree Stand Clamp Screw Thread Marginality"? It's a bit wordy, but it does convey the problem.

This Christmas tree stand has a clamp screw thread that's all but fully stripped.


The M8 screw won't apply pressure when tightened -- it just skips its female thread to no effect. (It never ceases to amaze me how manufacturers can't seem to master the simplest aspects of low-tech goods, yet they can produce high-tech items of stunning precision and perfection. It's a mystery.)

The female thread that's at issue here was poorly formed in thin material, hence the marginality.


What I'll do is fabricate a rectangular nut-plate from 3/32" thick steel flat. That will give me a nut that's inherently restrained from turning as the screw is turned. The nut-plate will tuck away neatly in its recess, and won't even be visible.

- - -

And here's the nut-plate fabricated and in place.


End of problem.

* * *

Not Quite -- SATURDAY, DECEMBER 31, 2016

The screw on the opposite side developed the same problem this year -- I gave it the same treatment as last time to repair it.

The root of the problem is not entirely with the female threads; the M8 screws are considerably undersize, contributing to marginal thread engagement. If there's a recurrence of the trouble, I'll replace all four screws as well as provide new female threads.

The stand's design is good, but the manufacturer's execution was poor. Properly made, one of these stands could last for generations.

One  wonders how many of these stands failed in this manner, and ended up in landfill. The waste is enormous, but then it's waste that makes the economy go round.


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