smorgasbord
Member
New video from him on installing acoustic panels on a ceiling:
At just a couple minutes in, he brings up the issue that measuring one panel when he needs like 12 across would multiply that error 12X, so better to stack the panels and then measure. Heck, I'd do that just in case the panels weren't built within a tight enough tolerance.
But, then he shows his work:
First up is the fractional math aspect: subtracting 137&3/16" from 137&⅞", which he gets right. But, then he's dividing 11/16" by 2 and getting 5/16" when it's 11/32". He doesn't work to 1/32" tolerances.
My head spun. I am SO glad I gave up imperial measurements! That whole thing becomes dirt simple:
Need: 3505mm (138")
Have: 3484.5mm (137&3/16")
(3505-3484.5)/2 = 10.25mm but it wants to undersize it a tad (he chose 1/16" since that's as tight as he works), so 9mm would be about perfect. And yeah, instead of subtracting the 1/16" from each edge first, since that's him erring on undersize rather than oversize, whether imperial or metric, he should do that at the end, not at the beginning.
Metric, thanks to decimal, wins hands-down every time. And that a mm is finer than 1/16" helps even more without getting crazy on what you can measure/cut by eye.
At just a couple minutes in, he brings up the issue that measuring one panel when he needs like 12 across would multiply that error 12X, so better to stack the panels and then measure. Heck, I'd do that just in case the panels weren't built within a tight enough tolerance.
But, then he shows his work:
First up is the fractional math aspect: subtracting 137&3/16" from 137&⅞", which he gets right. But, then he's dividing 11/16" by 2 and getting 5/16" when it's 11/32". He doesn't work to 1/32" tolerances.
My head spun. I am SO glad I gave up imperial measurements! That whole thing becomes dirt simple:
Need: 3505mm (138")
Have: 3484.5mm (137&3/16")
(3505-3484.5)/2 = 10.25mm but it wants to undersize it a tad (he chose 1/16" since that's as tight as he works), so 9mm would be about perfect. And yeah, instead of subtracting the 1/16" from each edge first, since that's him erring on undersize rather than oversize, whether imperial or metric, he should do that at the end, not at the beginning.
Metric, thanks to decimal, wins hands-down every time. And that a mm is finer than 1/16" helps even more without getting crazy on what you can measure/cut by eye.
