[TheForge] Re: Sound proofing a shop

[Mike Spencer]

BG> Dan's idea is correct, but stuff the gaps in between the studs
BG> with fiberglass. Even this won't stop low-frequency sound... the
BG> only thing that will stop that is mass.

Welll.... Some of you more technical guys can check me on this, but...

Low frequency sound, say in the 2 to 25 hz range, can be greatly
diminished or eliminated with very large baffles.  Imagine a wall of
concrete well crocks -- ca. 3' dia x 3' long -- stacked close-packed
and 4 high so you can see through the wall.  Diameter and length
affect the frequency of sound it will damp but I don't know the
relationship.

My reference for this is my vague recollection a circa 1958 Science &
Mechanics mag article about a guy who was building 6-foot diameter
plywood whatsits that worked sort of like police whistles: high volume
air, a large, flat box with a rotor that turned at X rpm.  Result was
a infrasonic sound pulse at X hz, [0 < X < ~30].  Baffle walls made
from large-diameter rings or tubes blocked the sounds he was
generating.

I doubt this would work for impact sounds -- 400# ram whacking anvil,
say -- because (I think?) such sounds have a broad spectrum with lots
of high-frequency components.  And of course, it would have no effect
on vibrations transmitted through the earth.

Jerry> You could always fill the walls with empty beer cans, they
Jerry> would have some sound deadening quality and it would be fun to
Jerry> do. In my case it's Diet Coke or Diet Pepsi.

You've heard about the house made from stacked embalming fluid
bottles?  They're square in cross section and this mortician saved
them up for years, then built a house.  Talk about a house that's
quiet as a tomb...

      But the greatest bottle building of all is on the shores of a
      lake near a little mountain hamlet called Boswell. David brown
      was an undertaker living in Red Deer, Alberta who contracted
      sleeping sickness because of the stress of his business. When
      his doctor advised him to quit brown loaded his trailer and
      headed west until he reached Kootenay Lake. Soon bored with
      retirement, Brown got a job selling embalming fluid and kept the
      empty bottles. He built his extraordinary house using 600,000 of
      them. Before he was half-finished, he was deluged with visitors.

      The two-storey house is 14 and a half metres long, and seven
      metres wide, and laid out in a cloverleaf patter with circular
      rooms. Insulation provided by the air trapped inside the bottles
      is equal to that of a metre of glass-fibre matting. The house
      reflects the sun and the waters of the lake.

      Brown died in 1970 but his son Eldon and his wife Diane Johnson
      have kept the place open to visitors.

      http://www.galleries.bc.ca/agso/sites2.html


J> Ah well. Wouldn't it be nice to be filthy rich? THink of all the silly
J> things you could have....

And Bill Gates doesn't own even *one* steam hammer or 200 T press.
Not even a 700# anvil AFAIK.  Imagine that.

Justin> Uh, start with "big" and "fast" and work your way up till you
Justin> couldn't afford it anymore. Like, say, an f-18 on your own
Justin> aircraft carrier.

The only time I ever got the hit with a pathologigical fantasy/desire
for the Ultimate Big Toy was when I heard about a US Navy maintanance
ship for sale.  On-board machine shop, foundry, forge, naval weapons
shop, capability to take smaller vessels on board, some kind of
floating drydock thing and other stuff I forget.  Essentially going
for whatever was scrap price at the time -- penny a pound or
something.

Roy> Around 30 years ago, I saw the ultimate "Screw the Joneses" in a
Roy> rail station parking lot.
Roy>
Roy>    A Maserati *station wagon*.

Too bad you didn't snap a pic with your digital cam. :-)

When I first moved here in 1969, there was a Rolls Royce pickup truck
parked out by a barn not too far away.  Having many other things to
think about -- turning a wreck back into a house, two-year-old twins,
trying to gadern in a new climate, setting up a forge in a woodshed,
learning to live without electricity etc. -- I never got around to
inquiring about it until it had disappeared and the old guy had died.
I still wonder what the story was.  [And yes, I'm sure it, or at least
the cab, was a Rolls.  I had just come from a couple of years as a
foreign car mechanic.]



- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^

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