Tactical generator environmental modifications

[tim292stro]

Keep in mind that ceramic or mineral fiber can be in direct contact with the exhaust/muffler, while other types of insulation/foam cannot (fire hazard) - I see that your muffler already appears to have a thermal/acoustic blanket on it (at least wrapped around the cylinder of it).

If you can put tires on your generator (makes it a bit easier to move too), you can run them "soft" and they'll work like air-bag isolators while the generator is running. Also keeps the generator from slipping off pads.

As I say, it's looking good, but I'm very interested in your intake/exhaust ducting - that's where most of your sound leakage will occur.

 

[dependable]

This is an interesting thread & nice work. Is the ceramic bead sound deadener like 'lizzard skin'? I have some 'raymatt' & lizzard skin left over from quieting some CUCVs, it never occurred to me to put on my 802.

I was running it yesterday in prep for today's blizzard, and noticed a lot of sound was coming from one of the lift rings bouncing. Wrapped a rag around it, but some kind of tape would be a more permanent solution.

 

[tim292stro]

...I was running it yesterday in prep for today's blizzard, and noticed a lot of sound was coming from one of the lift rings bouncing. Wrapped a rag around it, but some kind of tape would be a more permanent solution.

The ring will vibrate in its mounting tab - this can be countered by shimming it with teflon to remove the concentric play. It'll also vibrate against the skid, shooting the skid with some bed liner and acoustic dampening spray (Spectrum, Lizard Skin, Coat of Silence, Eastwood Sound Deadener, 3M 08864, etc...). This will also keep your rings from beating the paint off your skid, leading to corrosion. - you want to paint your rings, but not coat them with acoustic dampener, as chain or rope would tear/shear off the acoustic coating.

 

[Hard Head]

I just put a small piece if butyl dampener on the frame behind each lifting ring. I still coat all of my hooks and rings with plastic dip. I also coat the first 10 feet of my winch cables with it. I had the following polymers company recommend plastic dip to me for small jobs like this as it helps keep water from getting down in the layers of the winch, helps prevents rusting (especially the lead and eye), and it comes in multiple colors too. I even use it as a sealant at times. These guys make the coating for military helicopter slings

http://www.industrialpolymers.com/product-uses/coatings

I may try their products one day but for now a spray can of plastic dip is cheap and it works pretty good. They have some really cool stuff. I am going to get some styrospray to try out!

 

[Another Ahab]

I just put a small piece if butyl dampener on the frame behind each lifting ring. I still coat all of my hooks and rings with plastic dip. I also coat the first 10 feet of my winch cables with it. I had the following polymers company recommend plastic dip to me for small jobs like this as it helps keep water from getting down in the layers of the winch, helps prevents rusting (especially the lead and eye), and it comes in multiple colors too. I even use it as a sealant at times.

I may try their products one day but for now a spray can of plastic dip is cheap and it works pretty good. They have some really cool stuff. I am going to get some styrospray to try out!

I never heard if it as a spray. Used the dip, but maybe I should have used some kind if primer, because the dip always seemed to start failing after not too long.

 

[Hard Head]

I clean with acetone before I use paint of coat. It is funny stuff, you have to shake it up really good. Like you, I always had better results when dipping. When I spoke with the gentleman in the video we went back and forth about cost vs. gain. I guess I could just use a rust inhibitor coating on my cables but it I just coat after I exercise my winch every couple months to keep the spread the internal lubrication around. At one time I wanted to color the lead wire red which was a plastic dip color. Red and Black Georgia colors of course! Anyway it does hold up pretty good. I put silver on the first 3 feet for now. I do dip my clevis and hooks. I touch up with spray periodically. I even painted some stenciling with it as you can just peel it off when you are done!

 

[Ratch]

I added soundproofing material to my 803 when I had it apart for some cleanup. It helped a lot.
I added Mass-loaded vinyl to several panels, and inside the center upper cavity (where the contactor and current transformers are). I filled large gaps with expanding poly foam (Great Stuff) as a filler, which I then covered with a more acoustically-focused product.
MLV is not flame retardant, so it's probably not a great choice, but I did use it everywhere I could.
I also used large foam soundproofing (can't remember the name of the product) on any flat surface it would fit, on top of the MLV.

One thing that helps break sound is varying reflection surfaces. IE, a flat wall will more easily reflect sound or pass sound better than a rough wall. There are specifically designed random-surface sound deadening materials available, but probably too expensive and impractical for a mep interior. Anyway, point remains, even though we all like to see nice smooth uniform surfaces, a randomly varied surface will attenuate better.

In my 803, I ended up skipping battery box's and tie-downs, and used expanding foam to create new, vibration-resistant battery positions. It worked out better than I expected. Also provides some warning of mouse intrusion, when I fire it up for a test and white ground-up pieces of foam come flying out...
I also lined the bottom with expanding foam to break the consistent sound wave carriers. Not sure how effective it was, as the expanding foam itself is better as a mechanical insulator than sound insulator.

Anyway, the MLV is probably the best product for consumers like us to try. I'd put the thickest available or two layers if money was not an issue.

Regarding the ventilation being the loudest sound escape route, that's why it's facing up. Directing the sound upward sends it where it's least likely to be heard. That's also why the exhaust routes straight up, rather than to the side or down like on the prior generation of generators, which did not consider noise at all.
Diverting the cooling air and exhaust down will cause ground reflections and increase the noise radiating from the unit. If you spend a lot of effort making the enclosure quiet, you're really diverting a lot of sound out through the cooling ventilation. Directing that down is going to defeat all your acoustic work on the interior...unless it goes into a hole that then directs it back upward.

Edit: Just read that you're going to add baffling to the hood interior for acoustic control.


In any event, the hood looks good and should be very helpful at keeping the internals dry and protected from snow packing.

 

[Korgoth1]

I have used 2 layers of carpet foam and 1 layer plywood on a enclosure and it dropped from 84db to 75db at 7 meters. I bought a level 1 sound attenuated enclosure from them(paid high dollar for it too) and my rigged enclosure did better.

 

[Another Ahab]

I clean with acetone before I use paint of coat. It is funny stuff, you have to shake it up really good. Like you, I always had better results when dipping. I touch up with spray periodically. I even painted some stenciling with it as you can just peel it off when you are done!

Hey, THAT is brilliant. Did you get that idea on your own or catch it from somebody else?

That is a genius idea for temporary stencils.

 

[tim292stro]

Have you ever seen "dip your car"?

 

[Hard Head]

Well I didn't get the idea from dip your car but I did see a cop show episode where there was a robbery and the people painted the car blue with plastic dip and were peeling it off when they got caught. I didn't know this stuff came in so many options, cool , I will have to get some HyperShift Pearls and paint my land rover. Awesome!

 

[tim292stro]

Some movies where removable paint was used: The Jackal, TAXI (terrible US version)

 

[Hard Head]

Well you can spray your truck with gloss for parades and shows then peel it off when you want flat drab paint again. It should look nice and new!

 

[Another Ahab]

Have you ever seen "dip your car"?

Whoa! That's new to me; pretty cool.

 

[Hard Head]

Well I got the second and third spray coat done today. I had hydraulic project get in the way of doing more. It was 34 degrees in the shop and I had a torpedo heater trying to heat my spray booth so I ran the heater for 5 hours and left out at 6:30 tonight. I did get the OC 703 ordered and I really don't want to over 1" with another 1 inch patter in the middle of the door. I don't think that there is a whole lot more that can be done in a small space without over heating the cabinet. I cut slits in the door tool storage bin to increase the air flow. It was that or take the dang thing out. Just a note I will take care of any rattles from the wrench, ground rod connectors, and a few tools. I may carve out some gym floor foam I have to keep them in order. I will put Damplifier on both of the small doors tomorrow or just spray them. I coated the cabinet top spacer bar and will attach a strip of foam on it to slightly raise the center of the cabinet. I will do some experiments with different shape objects once I reassemble the cabinet and take sound measurements so I can determine what works and what is a waste of time and money. I have the new bolts, washers, and nuts. We have several silencers and reflectors built for the hood to test so I think we are ready to test. I was disappointed with the flimsy gauge of metal used for the cabinet! So guys don't worry about exhaust noise yet. I have a plan and the technology is as old as dirt

 

[Another Ahab]

Well I got the second and third spray coat done today. I had hydraulic project get in the way of doing more. It was 34 degrees in the shop and I had a torpedo heater trying to heat my spray booth so I ran the heater for 5 hours and left out at 6:30 tonight

You might want to watch putting down finishes where you're heating with a salamander heater like that.

It's been a long while and I forget the details now, but:

- Did a job years ago and had an epoxy floor in the project and we had just closed in the shell but the building HVAC wasn't completed yet.

- It was winter so we rented a few gas-fired salamanders and they heated the shell, sure.

- But later into the project we noticed that the epoxy didn't cure properly.

- Took us a while to put our finger on the culprit, but as I remember it between us and the A/E team we figured it was the water vapor and CO2 from the salamander that imbalanced the cure.

We took a hit; the floor had to come out and be replaced. But it was the whole building team that shared the hit; the A/E approved our request to use the temporary heat. Contracting: it "ain't" always pretty.

 

[Triple Jim]

Whoa! That's new to me; pretty cool.

I'm currently repainting a motorcycle I bought that was sprayed with Plasti Dip. The problems include poor abrasion resistance, demonstrated by the stuff peeling off in places like the gas tank sides where the rider's knees rub, and by rapid dissolving from any minor amount of spilled gasoline, no matter how quickly you try to wipe it off. And it peels off only if it's put on thick enough. Where the coating is thin, you have to dissolve it off with something like mineral spirits. It has some really neat uses, but some big limitations too.

 

[Hard Head]

checked with the vendor and the kero heater is npt a problem. Just have to keep the the room above 50 for 24 hours min. 7 days to fully cure. I checked and I am 1 mm too thin so I will apply another coat. It is hard to tell how thick you are applying since an undercoating gun creates a lot of splatter. You can roll or brush this too. Since I am going to put another product over it I would brush and roll it next time. I the coating was exposed I like the look of the spray. So I guess it just comes down to what is easier and works. I think if you are just doing one product this is better than the stick on butyl. When doing more than one the stick on is faster as long as you can get to every surface. Everything is warned up this morning so I will finish and let them cure for 7 days and assemble and go from there with additional product. This way I can try different materials and measure the sound level as each product used. Hopefully doing so will give me an idea of the cost benefit of the material tested. I hope it will be warmer next week! I will get a second generator ready so we can look at it's sound levels compared to this generator. I will do a video once we get done of each one running in the same exact spot with db reading. Again this is not just about sound! It is about all of the conditions I am currently faced with the generator. Sometimes you give up something to make another thing better. Of course I don't want to, but I will if it ensures that when needed I don't have to worry about rodents, wasps, ants, ice, snow, water, and waking the dead. Knowing the condition of the major components of the generator while not running and running is important when you want an automatic start and transfer. There are other really good threads on this. I will also show what I use in the end to make it turnkey.

 

[Another Ahab]

checked with the vendor and the kero heater is npt a problem. Just have to keep the the room above 50 for 24 hours min. 7 days to fully cure. I checked and I am 1 mm too thin so I will apply another coat. It is hard to tell how thick you are applying since an undercoating gun creates a lot of splatter.

These thicknesses are so thin and tiny, Hard Head; how in the heck are you measuring them?

 

[Hard Head]

I just use calipers and a micrometer.