Here’s one that didn’t work. I picked up a bag of 1-1/4” hose at the hardware store that’s sold for sump pumps. Visually, it looks almost identical to 1-1/4” vac hose, almost.
I had visions of using it to make some sort of sanding / dust collection station, similar to the Festool vac using my ShopVac.
So it’s a 1-1/4” hose what’s the big, deal right? Well this hose is just enough different from the hose that’s sold for vacs to big a HUGH problem. For some reason it generates a deafening harmonic. I mean a squeal that would make your ears bleed if you didn’t have hearing protection in. I wish I was joking.
I did try cutting a shorter length of hose to try:
This is better. It still has the same harmonic but the amplitude is much less and depending on how I hold the sander, I can make the harmonic go away. I suspect that I may be restricting the air flow just enough to dampen the harmonic. Otherwise it goes into the under-damped region and squeals.
If anyone has any ideas on how to possibly dampen the harmonics, I sure would love to hear them.
-- Chunk's Workshop pictures: http://spadfest.rcspads.com/thumbnails.php?album=135