Sound level and mufflers on small mills

[gemniii]

I'm looking at getting a small mill, Oscar 18, Woodmizer LT10, Cooks MP24 or some similar SMALL mill.
One of it's initial uses will be in neighborhoods where I'd prefer to make no more noise than a lawnmower.  Yet I will also be using it where I can't run power to it, so an electric motor is not a consideration.

I searched on muffler and noise and didn't find anything useful.

What type mufflers are run on the smaller saws and has anyone "upgraded" their muffler to make it quieter?

What's the noise level of the smaller mills?

[John Bartley]

When I bought my 25hp, Kohler V-twin powered mill, I wanted an answer to exactly the same question. I called our provincial Ministry of the Environment and the answer kind of set me back a bit. In Ontario, every piece of noise producing equipment sold is "supposed to have" a certificate of compliance for noise. I sold commercial grass cutting equipment as a business for many years, and I've never seen one of these certificates, and when I inquired, nobody else in the business, including the distributors had ever heard of this. I checked the legislation to be sure, and it was right there in black and white. I went back to the Ministry and was told that they aren't overly concerned about the certificate, "they are a complaint driven process" ministry, and that in the event of a complaint they would first ask me to remedy the noise problem, and then if I was unwilling to do so, they would take action. In my case the remedy would have been simple.....pack up and leave the job.

But.....this above doesn't answer your question does it?

So.......the simple answer is that the engines and exhaust systems used on the mills are the same as those used on commercial grass cutters, stump grinders, brush chippers (etc.) in residential areas, so noise is not likely going to be an issue, mostly because your time in any one area will likely be quite short (a few days at a time), and can be explained away as a "temporary" inconvenience to those who object.

You may wish to ask your local bylaw and/or environment regulators for an opinion.

cheers

John

[stonebroke]

There are some low noise mufflers for atvs. I think I saw them in cabelas catalog once. You might be able to adapt them.

Stonebroke

[bandmiller2]

Usally not a problem, especially for mobile mills,the mufflers supplied are usally sufficient.My bandmill is powered by a wisconsin 2 cyl,I made a secondary muffler attached to the output of the standard muffler dropped the noise level noticably.Alot has to do with the direction of the exhaust,a pipe extension pointing up seems to reduce it.Mufflers vary so much its hard to give specifics.Many engine builders offer different options.I was concerned with the exhaust noise from my 6 cyl Dagenham diesel on the circular mill,a simple muffler solved it besides the saw makes more noise than the engine.If your muffler has an exit pipe add a second small resinator [muffler]or verticle pipe just support a heavy unit to not stress the manifold.Frank C.

[moonhill]

My mill is louder than the typical riding lawn mower or even the my tractor which has a similar engine, 3 cylinder diesel engine.  I have not listened to a all electric band mill but I guess it makes more noise that one would think. 

Tim

[ljmathias]

I took a more direct route and just put a matched pair of mufflers on my head- cuts out most of the noise and the side benefit is I can't hear my phone when it rings...   

Lj

[jdtuttle]

I wear ear protection & have a 25 hp kohler. Spent too many years in construction & want to protect the hearing I have left
jim

[ljmathias]

What?  What did you say?  Speak up sonny...   

Lj

[scsmith42]

I've run across this same problem.  It seems as if there are some good quiet mufflers available for two cylinder engines, but very few that work worth a darn for one cylinder engines. 

Jack's Small Engine website has some good options for mufflers.  I've used the SuperTrapp versions on some equipment and they work well.

I built a muffler for a single cylinder Onan engine a couple of years ago, and it turned out very well. The noise level went from "hurting your ears" loud to being able to carry on a conversation next to the generator.  It was a conbination of a 4" diameter - 18" long resonator / baffled expansion chamber with a super trapp muffler on the eventual outlet.  The concept of the muffler was copied from a firearm supressor, and it really worked well.  I can sketch it up if anybody is interested.

[Brad_S.]

Engine noise accounts for only part of the noise the mill puts out. You may be suprised at the amount of "singing" the band does as it sails around the wheels. The combined noise is enough to have to make you shout at the top of your lungs to communicate, but unless you were to saw daily in a residential area, the noise is tolerable, IMO.

[ErikC]

  I have been surprised at how much noise the mill seems to make, and then people a short distance away not even noticing it. I think on mine the blade makes a higher pitch than the motor and from aways away all you hear is that zing. Anyway I wouldn't worry too much over it.

[gemniii]

Jack's Small Engine website has some good options for mufflers.  I've used the SuperTrapp versions on some equipment and they work well.

I built a muffler for a single cylinder Onan engine a couple of years ago, and it turned out very well. The noise level went from "hurting your ears" loud to being able to carry on a conversation next to the generator.  It was a conbination of a 4" diameter - 18" long resonator / baffled expansion chamber with a super trapp muffler on the eventual outlet.  The concept of the muffler was copied from a firearm supressor, and it really worked well.  I can sketch it up if anybody is interested.

Thanks for the link, and I'm sure everyone would appreciate a sketch.

[coastlogger]

SCSmith:
I for one am interested in your muffler accomplishment.A sketch would be great. Speaking of ear muffs anyone use the kind with aradio in them? I recently got a pair and find that they can, if used selectively, really make a bad day go better.
clgr

[Brad_S.]

There was a discussion about them a while back. Some, like myself, love them and can't imagine sawing all day without some music. Others thought they were a safety hazard, that you need to hear the motor and the blade talking to you. It's like the water/diesel lube issue. People have strong opinions about them and no amount of discussion will change anyones view either way.

[Magicman]

People have strong opinions about them and no amount of discussion will change anyones view either way.  

Well said......

[ErikC]

People have strong opinions about them and no amount of discussion will change anyones view either way.  

Well said......

Yeah a guy could just about say that on any topic couldn't he? Very true but we still like to hear all the points of view.

[Magicman]

  Yeah a guy could just about say that on any topic couldn't he? Very true but we still like to hear all the points of view.  

Oh, it's all "tongue in cheek",  Some of the best lessons that I have learned was when I was wrong   

[backwoods sawyer]

Being 100% portable I am either milling out by the barn or next to the house in some neighborhood. I run a 42 hp Kubota and liken it to the noise of a small tractor. As far as the noise from a saw singing, a little lube will quite it down right now, and a side benefit is it is lube for the saw as well.

[Norm]

Mine's all electric and is amazingly noisy.

Funny thing is I've never used a portable mill with a combustion engine....yeah I do need to get out more.

[bandmiller2]

Really most of us with bandmills work close to the mill and they seem louder to us than the person in the next yard.As stated much of the noise is not from the exhaust but the band and general engine clatter.I also run an electric and its far from quiet.Frank C.

[moonhill]

Mine's all electric and is amazingly noisy.

Funny thing is I've never used a portable mill with a combustion engine....yeah I do need to get out more.

That's what I thought, even with some cutter running on the band. 

Radio head phones are great.  I can hear the up and down of the engine, the wine of the band saying thing and I even know when I hit a spike, they don't cut all the noise out.  I am working on my third set. 

Tim

[Ironwood]

My experience is that twin engines are quiter than single cylinders.   ??  And the guides on my Norwood are noisier than anything else. I have used mills w/ guide block style guides and they are quieter. I dont mind the noise, and like the factory guides on the Norwood (no adjusting). Just a few points of input.

       ironwood

[Papa1stuff]

I have worked on construction all my life and never wore ear protection and even after I got my LT40 Super with the 51 Cat ,I still did not think I could hear the changes of sound that tell you something may be wrong while wearing ear protection.
Well I finally tried ear muffs and after a very short time I found out you still can hear any problem noise and now It hurts not to wear them

[John Bartley]

I have worked on construction all my life and never wore ear protection and even after I got my LT40 Super with the 51 Cat ,I still did not think I could hear the changes of sound that tell you something may be wrong while wearing ear protection.
Well I finally tried ear muffs and after a very short time I found out you still can hear any problem noise and now It hurts not to wear them

Very true!

I spent a couple of years underground as a miner when I was young. I followed that up with machine shops, engine shops, etc... I only started wearing hearing protection in my '40's and I sure wish I had started in my teens.....

cheers

John

[Magicman]

The only problem that the noise from my mill in urban areas has caused, is the folks it draws in.  Pretty soon, there is a crowd.  They want to ask questions.  And out comes the cameras.  Then, with everyone watching and distracting you.......guess what    Yup, you screw up,    and then try to make folks think that you ment to do that......

Did I ever tell you that I love portable milling....    

[bandmiller2]

I'am as guilty as anyone,I like to hear the old diesel and the saw ,the feedback helps but probibly a mild form of hearing protection would be best.To each his own but I don't think I'd listen to tunes wile running the mill.Frank C.

[stonebroke]

The only problem that the noise from my mill in urban areas has caused, is the folks it draws in.  Pretty soon, there is a crowd.  They want to ask questions.  And out comes the cameras.  Then, with everyone watching and distracting you.......guess what    Yup, you screw up,    and then try to make folks think that you ment to do that......

Did I ever tell you that I love portable milling....    

Just view them as potential customers

Stonebroke

[stonebroke]

Just view them as potential customers

Stonebroke

[Magicman]

Just view them as potential customers.   Stonebroke 

Many times they are !!!  That's why I love it......    

Urban sawing has put me on the Front Page of our local newspaper.....twice......

[scsmith42]

SCSmith:
I for one am interested in your muffler accomplishment.  A sketch would be great.

As requested, a sketch is attached via an Excel file.

Here are some more details:

The design concept is to trap noise waves inside the muffler while allowing low restriction path for gas to escape.  My muffler has three sections - an inlet chamber, baffle section, and exhaust chamber.  Note that pipe outlet inside of inlet chamber faces away from the baffle assembly.  Also note that exhaust nipple exits through the side of the muffler, minimizing potential for sound waves to exit with exhaust.

The inlet chamber also serves as an expansion chamber.  It is a good idea to use a double wall on the end of the chamber, since the discharge of the inlet pipe points directly at the end of the muffler.  Doubling the end wall will reduce external heat and also increase the longevity of the muffler.

The discharge side of the inlet pipe faces away from the baffle assembly in order to create an initial sound wave trap inside the expansion chamber.  I use black iron pipe fittings for my inlet fittings, sized to match the exhaust port on the engine (typically 1”).

By having the exhaust exit from the side of the exhaust chamber, rather than the end, sound waves are further captured inside the muffler.  If you need an end exhaust, consider installing a pipe elbow on the outside of the muffler (screwed into the exhaust nipple).

The I.D. of the hole in the center of the baffles should be approximately the same size as the I.D. of the inlet pipe (i.e. same size as the exhaust port).  It can be slightly smaller or larger.

I used a hydraulic press to bend a flat shim washer into my tapered baffle.  It was a simple matter of supporting the perimeter of the washer while pressing down in the middle to reform it into a cone.  The shim washers that I used were originally made for shimming bearning in heavy equipment final drives, but you can also make your own from sheet steel.

One additional goal of the muffler is to slow down the speed of the exhaust through it, as well as allowing the hot gasses to cool somewhat.  This also helps to reduce noise.

For maximum sound reduction, add a Super Trapp muffler /resonator to the exhaust port from the muffler.  I used a Model 3S with the optional resonator for my installation http://www.jackssmallengines.com/strap3s.cfm.

I built my prototype for an old Onan one cylinder generator.  The generator had a shroud around it, effectively trapping most of the non-exhaust noise from the motor.  Prior to the installation of my muffler, the generator was “hurt your ears” loud.  After installation, two people could carry on a conversation at normal levels ten feet from the generator.

Building this muffler is neither fast nor inexpensive.  It took me a couple of days to build my protoype.  As I recall I spent around fifty bucks on tubing, pipe fittings and the interior components.  The Super Trapp option alone adds another hundred bucks or so to the overall cost.  However, if you are in a situation where you have to spend a lot of time listening to very loud single cylinder gasoline engine, then the investment may be worthwhile.

My prototype has been operating for over two years w/o any problems or reduced generator power.

[Toolman]

The only problem that the noise from my mill in urban areas has caused, is the folks it draws in.  Pretty soon, there is a crowd.  They want to ask questions.  And out comes the cameras.  Then, with everyone watching and distracting you.......guess what    Yup, you screw up,    and then try to make folks think that you ment to do that......

Did I ever tell you that I love portable milling....    

    A couple years back, I was sawing for a guy near a residential neighborhood. The cameras were out, a small curious crowd gathered  including a gorgeous  young college girl that made heads turn from passing motorists. A piece of wood fell from my cut onto the cutter head track. As I raced up to remove the piece, my foot hooked perfectly around the log loader and down I went.  I felt goofy to say the least. I did put a smile on the young girls face. Was'nt quite the way I wanted to do that.