Genset soundproofing -- seeing light at the end of tunnel

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

I want to, first, thank everyone for your suggestions, even for the ones
that I did not adopt. All of your ideas were valuable to me. I cannot
literally think of even one post which did not have some bit of useful
info or food for thought.

I am almost at the end of the work of making a generator enclosure and
soundproofing it. I bought lead sheet and attached it to plywood
panels. I need (and can) do a better job at sealing all holes and in
fact on one side I have not even completed the enclosure.

http://igor.chudov.com/tmp/onan/Diesel/Enclosure/

(I beg you to not xpost it to rec.woodworking)

I ran the generator today.

Despite this incompleteness, the enclosure appreciably reduces the
noise. At 10 feet, with the access door open, the noise is 85 dB. With
the access door closed, it is 79-80 dB. It also feels rather tolerable
to be around this working genset. I would not mind it working all day
long. It is much quieter than, say, my snowblower (87-89 dB).

Another good news is that, perhaps due to its weight as well as
vibration isolation by two used tires, the enclosure basically does
not vibrate.

I have hopes that when I am really done with this work -- have fewer
and smaller and baffled gaps and openings etc -- I can slash 3 or so
decibels from this, bringing noise down to sensible 76-77 dB.

The enclosure's panels are held by wingnuts and it is designed for
very quick disassembly, because it is relatively heavy.

Plans:

0. Finish the opening for cooling air intake and seal gaps better.

1. Weatherproof the enclosure, I will use epoxy on top and oil based
deck stain on the sides (to match the deck and shed nearby).

2. Finish the electrical panel. I will make it based on a 12x24 1.5 mm
thick aluminum sheet that I bought at Menards. The current electrical
panel will be junked. The new one will have numerous gauges, a ON/OFF
switch, and easy access to connect the power cable.

3. Make a foundation from 2x2' patio blocks.

4. Install the genset on it.

5. Install transfer switch of some sort.

Thanks to all!

i

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

On 24 Jan 2005 00:06:46 GMT, Ignoramus9778
<ignoramus9778@NOSPAM.9778.invalid> wrote:

> I want to, first, thank everyone for your suggestions, even for the ones
> that I did not adopt. All of your ideas were valuable to me. I cannot
> literally think of even one post which did not have some bit of useful
> info or food for thought.
>
> I am almost at the end of the work of making a generator enclosure and
> soundproofing it. I bought lead sheet and attached it to plywood
> panels. I need (and can) do a better job at sealing all holes and in
> fact on one side I have not even completed the enclosure.
>
> http://igor.chudov.com/tmp/onan/Diesel/Enclosure/
>
> (I beg you to not xpost it to rec.woodworking)
>
> I ran the generator today.
>
> Despite this incompleteness, the enclosure appreciably reduces the
> noise. At 10 feet, with the access door open, the noise is 85 dB. With
> the access door closed, it is 79-80 dB. It also feels rather tolerable
> to be around this working genset. I would not mind it working all day
> long. It is much quieter than, say, my snowblower (87-89 dB).
>
> Another good news is that, perhaps due to its weight as well as
> vibration isolation by two used tires, the enclosure basically does
> not vibrate.
>
> I have hopes that when I am really done with this work -- have fewer
> and smaller and baffled gaps and openings etc -- I can slash 3 or so
> decibels from this, bringing noise down to sensible 76-77 dB.
>
> The enclosure's panels are held by wingnuts and it is designed for
> very quick disassembly, because it is relatively heavy.
>
> Plans:
>
> 0. Finish the opening for cooling air intake and seal gaps better.
>
> 1. Weatherproof the enclosure, I will use epoxy on top and oil based
> deck stain on the sides (to match the deck and shed nearby).
>
> 2. Finish the electrical panel. I will make it based on a 12x24 1.5 mm
> thick aluminum sheet that I bought at Menards. The current electrical
> panel will be junked. The new one will have numerous gauges, a ON/OFF
> switch, and easy access to connect the power cable.
>
> 3. Make a foundation from 2x2' patio blocks.
>
> 4. Install the genset on it.
>
> 5. Install transfer switch of some sort.
>
> Thanks to all!
>
> i

I did a bunch of research on soundproofing some years ago and on seeing
your pictures, I can tell you that you'll be able to drop the noise output
quite a bit when you finish the enclosure. Sound is transmitted by moving
air, so you want as few holes for air to escape the enclosure as possible.

Then again, running an engine in a closed box without ventilation isn't
such a good thing. But there are ways around this as well...

Good luck. Sounds like you've got a solution you can live with and
ultimately, that's what matters.

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

On Sun, 23 Jan 2005 19:23:10 -0500, Astro <Astro@spammenot.com> wrote:
> On 24 Jan 2005 00:06:46 GMT, Ignoramus9778
> I did a bunch of research on soundproofing some years ago and on seeing
> your pictures, I can tell you that you'll be able to drop the noise output
> quite a bit when you finish the enclosure. Sound is transmitted by moving
> air, so you want as few holes for air to escape the enclosure as possible.

Thanks, I have similar hopes as well.

> Then again, running an engine in a closed box without ventilation isn't
> such a good thing. But there are ways around this as well...

Well, the engine ventilates itself and exhausts warm air through a
opening in the cover, which "ducted" to outside. The duct is visible
on the first picture, I believe.

http://igor.chudov.com/tmp/onan/Diesel/Enclosure/

I will apply some sound dampening substance to the duct and engine
panels also. Maybe something as simple as electrical tape.

> Good luck. Sounds like you've got a solution you can live with and
> ultimately, that's what matters.

I agree. It is now becoming an acceptable situation, a generator that
is weatherproofed and that is almost quiet enough.


i
--

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

"Ignoramus9778" <ignoramus9778@NOSPAM.9778.invalid> wrote in message
news:ct1e6m$oa7$0@pita.alt.net...
> I want to, first, thank everyone for your suggestions, even for the ones
> that I did not adopt. All of your ideas were valuable to me. I cannot
> literally think of even one post which did not have some bit of useful
> info or food for thought.
>
> I am almost at the end of the work of making a generator enclosure and
> soundproofing it. I bought lead sheet and attached it to plywood
> panels. I need (and can) do a better job at sealing all holes and in
> fact on one side I have not even completed the enclosure.
>
> http://igor.chudov.com/tmp/onan/Diesel/Enclosure/


I built my genset housing out of concrete blocks and a rebar reinforced slab
for the roof, hand-poured. The inside walls are lined with 3/4" hard
fiberglass ceiling tiles circa pre-1974. The enclosure is fireproof,
weatherproof and nearly soundproof. Even the door is filled with concrete.
To do items include externalizing the muffler system and forced-air cooling.
But it's going on 20 years that the 'bunker' style enclosure has housed our
generator and it's been maintenance-free. Of course, it's not as portable as
yours (it's not portable at all in fact, but that deters theft). :-)


--
Best Regards,

Mark A. Weiss, P.E.
www.mwcomms.com
-

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

"Ignoramus9778" <ignoramus9778@NOSPAM.9778.invalid> wrote in message
news:ct1nha$qft$2@pita.alt.net...
> On Sun, 23 Jan 2005 19:23:10 -0500, Astro <Astro@spammenot.com> wrote:
> > On 24 Jan 2005 00:06:46 GMT, Ignoramus9778
> > I did a bunch of research on soundproofing some years ago and on seeing
> > your pictures, I can tell you that you'll be able to drop the noise
output
> > quite a bit when you finish the enclosure. Sound is transmitted by
moving
> > air, so you want as few holes for air to escape the enclosure as
possible.
>
> Thanks, I have similar hopes as well.
>
> > Then again, running an engine in a closed box without ventilation isn't
> > such a good thing. But there are ways around this as well...
>
> Well, the engine ventilates itself and exhausts warm air through a
> opening in the cover, which "ducted" to outside. The duct is visible
> on the first picture, I believe.
>
> http://igor.chudov.com/tmp/onan/Diesel/Enclosure/
>
> I will apply some sound dampening substance to the duct and engine
> panels also. Maybe something as simple as electrical tape.
>
> > Good luck. Sounds like you've got a solution you can live with and
> > ultimately, that's what matters.
>
> I agree. It is now becoming an acceptable situation, a generator that
> is weatherproofed and that is almost quiet enough.
>
>
> i
You might like to do some searches on Outside Broadcast generator sets.
There is a fair bit of stuff out there, including sound proofing boxes.

I recall some years ago standing beside a BBC 50kW diesel OB genset
(on a fair size truck) that I could barely tell was running.

Looks like you are well on the way though.

Regards
Ian

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

I have the same generator. In December I went out to check it out and
found that mice had gotten into the electrical box and really made a
mess. I have made most of the obvious repairs, but the breaker on the
regulator trips as soon as the engine starts. Onan says to replace the
card, but first I'll take it to work and let my techs look at it. Have
you found any of these as parts machines?

Bob

Archived from groups: alt.energy.homepower,rec.crafts.metalworking,rec.audio.tech (More info?)

> >
> >
> > I built my genset housing out of concrete blocks and a rebar reinforced
slab
> > for the roof, hand-poured. The inside walls are lined with 3/4" hard
> > fiberglass ceiling tiles circa pre-1974. The enclosure is fireproof,
> > weatherproof and nearly soundproof. Even the door is filled with
concrete.
> > To do items include externalizing the muffler system and forced-air
cooling.
> > But it's going on 20 years that the 'bunker' style enclosure has housed
our
> > generator and it's been maintenance-free. Of course, it's not as
portable as
> > yours (it's not portable at all in fact, but that deters theft). :-)
>
> That's interesting. How much access space do you have for repairs and
> maintenance?
>
> i

I have a wooden platform that I place in front of the entrance to the
blockhouse and I simply roll the genset out on to the platform to change
oil, filters, etc. Works pretty well.
Key importance is to have good fans pushing cool air from the outside in and
through the blockhouse to cool the generator. Until I relocate the muffler
system, I just open the door and the muffler is right there, so the exhaust
goes right out.


--
Take care,

Mark & Mary Ann Weiss

VIDEO PRODUCTION • FILM SCANNING • DVD MASTERING • AUDIO RESTORATION
Hear my Kurzweil Creations at: http://www.dv-clips.com/theater.htm
Business sites at:
www.dv-clips.com
www.mwcomms.com
www.adventuresinanimemusic.com
-