Here's A ??? I Have Not Seen Asked

Not only that but, the wheel and flange to rail contact is markedly smaller, thus should be much quieter. Every 2-Rail SCALE operating layout I have ever visited is MUCH quieter, than most 3-Rail layouts.

Even on 3-rail flat-top rail, 2-rail wheelsets are quieter than three-rail. This is even true on Gargraves/Ross hollow rail. The center rail isn't much of a contributor as it's not load bearing and is typically contacted by fewer "wheels", especially in my case.

Matt & Hot Water,

Dad-gummed, I learned something new today, Thank you! 

I always thought tubular track inside Johnson's rubber roadbed was very quite.

So, what you're saying is that in addition to less track and number of wheels/rollers, the smaller diameter (and/or width) of the 2-rail wheels means less metal to metal contact at any one time?

Or is it just that the mating of the metal between track and 2-rail wheels is of 2 flat surfaces touching, making it quieter than a flat surface (track) and an angled surface (Hi-angle wheels) rubbing on one another?

What are 2-rail wheels mainly made of?  Most 3-rail wheels are cast XXX (what material are these things!).

I should name my posts "Going Off The Deep End Again"

atlas 3 rail,outside loop much noisier than atlas flex 2 rail,inside loop but it is all good.

@   beginning  east bound CSX BNSF 4 engine multi unit
    @  .55  west bound Guilford Pan Am  5 engine multi unit
    @ 1.54  east bound Guilford 2 unit switching track

Visit a three rail club layout then visit a two rail club layout.  The added equipment of a club sized RR will make a bold  statement of which style is louder.  I'm usually only good for 5 or 10 minutes with a lot of three rail trains running.

My neighbor has a large 3rail pike and conversation is difficult.  Much like in a sports bar.

I run on HO & N layouts.  The biggest sound difference between 2 and 3-rail is that most 3-rail engines have sound systems while many 2 rail engines do not.  The sound of a steamer chuffing or a diesel engine running seems to be the dominant contributor to layout noise if the track is well ballasted.  Even smaller scale layout become noisy when there are engines with full sound systems running.

Joe

That is true to a large extent, but you can definitely hear a difference in the track noise from 2-rail rolling stock vs 3-rail rolling stock on the same track. I hear it every weekend down at the club. Solid rail is quieter than hollow rail. Smaller solid rail is quieter than larger solid rail. It is what it is.

I think it depends a lot on the ties, ballast, and sub-roadbed.  My handlaid track is noisier than my plastic tie Atlas.  I prefer noiseless operation, and I come close with plastic ties on Celotex with splined sub-roadbed.  Milt Sorensen had some kind of outdoor carpeting under his TruScaleroadbed, and you simply could not hear anything.  I think the closest you could come to that now is wet-suit rubber, or maybe old inner tubes.

I like the occasional sound-equipped locomotive, but a steady diet of that stuff becomes noise.

For those of you who had 3-rail and went 2-rail, is 2-rail quieter than 3-rail at the same speed?

 

It would seem it would be, after all, you've eliminated 33% of the rail and the center rollers that ride on it.  Given all other factors are the same it would only make sense.

Bob

A 2 rail layout may have 1/3 fewer rails but that ratio doesn't hold when you count the points of contact with the rails.

Take a 20 car freight train with two geeps and a caboose.  It would have 192 wheels plus contact wipers in 2 rail.  In three rail it would have 192 wheels plus a maximum of 10 rollers.  That is about a 5% difference, not too much.

Every 2-Rail SCALE operating layout I have ever visited is MUCH quieter, than most 3-Rail layouts.

Most of us would agree with Hot Water about that.  But I don't think that the major source of the difference comes from rolling stock, it comes from typical layout construction.

If you hang out with many three railers you are likely to hear the phrase "train table" come up in conversations about layouts.  Many, many three railers have never read magazines like MR or any other source of scale oriented layout construction articles or layout construction books.  You have a lot of 3 rail 4x8 layouts and many larger layouts are built by expanding in multiples of 4x8 sheets of plywood.  Most three rail track is either tubular or comes with molded in roadbed.  And often that sectional track is laid directly on the plywood which turns the sheet of plywood, often screwed or nailed to a 2x4 frame, into a highly effective speaker diaphragm.  Screw another sheet of plywood to the bottom of the "train table", cut F holes in it and it would sing like a death metal band in an 11th grade talent contest! 

Two rail layouts are much more likely to be built with 3/4 inch plywood cookie cutter sub-roadbed topped with homasote or cork supported by 1x4 open grid or L-girder benchwork.  You won't be likely to find any hollow rails or 10 inch pieces of sectional track with or without molded in roadbed or any sub-36" radius curves taken at mainline speeds.

The Northwest Trunk Lines is a 3 rail layout with curves of 36" radius or greater (except for the 2 rail narrow gauge)  built with 3/4" plywood or spline subroadbed, Homasote or Homabed above that and solid nickel silver rail with staggered joints over 30" apart soldered together with Right-of-Way fish plates.  Carpeting and scenery deaden reverberations in the room.  It is very quite.

If anyone has a dB meter bring it on over to the NWTL.  Then measure the noise level at a similarly constructed 2 rail layout with a similar train at the same speed.  An apples to apples comparison would be interesting.

I agree.

Often I skip threads with non- descriptive titles.  I bet you would get a lot more opinions if you put the general subject in the title.  Only reason I opened this one is I didn't want to do lesson plans.

Ted, good catch on the center rail, on a typical freight train the engine(s) and caboose would be the only things with center rollers.

My use of 3/8" thick rubber anti-fatigue matting, cut into strips for roadbed, made a big reduction in noise.  Adding ballast seemed to add some of  it back.

I'm starting to appreciate the "Less noise is better" approach.

If you glued down your ballast with white glue, it dries rock hard.  If you use matte medium, or "Matte Matte" from Michaels or Hobby Lobby, the ballast gets glued down, but is a bit "spongy".  I and others have noticed a reduction in ballast noise when we used a matte material to glue down ballast. 

Strictly opinion based on actual observations in HO and O three rail.

Regards,

Jerry

Thanks Jerry!

Some of it is matte medium while most was an experiment with True Scene Modeling's Fusion Fiber.  I mushed the fiber down in between each tie then topped it off with ballast.  The Fusion Fiber is great for ground cover but when dry it's VERY dry and I think that's where a lot of my noise is coming from.  It's still not a lot of noise, but I know it can be made quieter.

Of course if I go 2-rail it'll all have to come up, not sure if I'll ballast any new track.

If I could cut out the anti-fatigue mating for the ties to sit down in that would take care of everything.  It's a shame we don't have a hobby laser that would make precision depth cuts.

"Many, many three railers have never read magazines like MR or any other source of scale oriented layout construction articles or layout construction books. "

Sad, but true.

Most 2-rail layouts I have visited have been very quiet.

Now if you are comparing a 2-rail layout to Fastrack, whoah Nelly!

 "is 2-rail quieter than 3-rail at the same speed?"

    I can't recall ever seeing a 3 rail layout run at realistic speed so it's hard to say. If one is modeling modern welded track era perhaps a quieter track would be ok but if modeling the jointed rail are the more noise the better.Anyone who's ever paced a 50's era freight train knows the track and wheel noise is greater than the loco noise at speed.....DaveB

Even creeping along at 20 mph 2 rail is quieter than the 3 rail layouts I've seen. In addition, the type and brand of equipment run seem to add to the noise. On Gargraves and Ross our MTH freight cars are louder, the Lionel Husky Stack is almost whisper quite. Cars with center rail pick-up rollers have those to add noise. Think the loudest things ever brought over were a high speed Pre-War Flying Yankee and an Aero Train.

Time permitting, will try some tests with all kinds of freight cars and a sound meter tonight. See how some box cars match up against each other. 

Lima, thanks and let us know what the results are   I should have gotten a decibel meter from Radio Shack when I had the chance, oh well.

Actually NOT that much difference once you turn OFF the "Railsounds"!!!

Sorry Bob, couldn't resist.

Simon

I have a 2 rail scale layout and a 3 rail layout. They have the same ballast and I glued it so it is "hard". Both layouts share the same tables.  The 3 rail track is Atlas and the 2 rail track is Microscale Engrg. The difference in sound level is remarkable, and I think the principal reason is the much smaller flanges on the 2 rail equipment. I bought and used a Radio Shack decibel meter for about $50 and have used it to determine my noise sources and investigate ways to reduce the noise level, so I could "hear" the engines! (I have a concrete basement floor, framed photos on the walls, and a drop ceiling with a skin coating to prevent white "flakes" on the layout.) Unfortunately, the concrete, the glass photos, and the hard skin ceiling all reinforce sound. The easiest way to reduce sound in "anything" is to reduce it at its source, and that is the train. That is why I am making a valiant attempt to get my 2 rail cars to operate through 3 rail Atlas turnouts.

Sound is measured using a log scale, and approximately every 3 decibels the sound energy is doubled (but not the apparent sound that a human ear "hears".) A two rail train running on 3 rail track at a prototypical speed of 60 smph is from 8 to 12 decibels quieter than the same size and car type 3 rail train running on the same track. That's a lot!

One theory that I have is that a 2 rail train is quieter because the tread taper of two rail wheelsets is closely matched to the rail profile at the top, just like on real railroads. (On a real railroad, the wheel taper acts to "center" the car on the track, to minimize flange contact unless it is required, such as on curves.) On a 3 rail train, the "fast angle" wheel taper bears almost no relationship to the top of rail profile, so the cars do not "center" and the flanges are almost always rubbing. (How shiny are your flanges!?) If the three- rail manufacturers would just get away from the cheap sintered "fast angle" wheels they now use, even just on their premium rolling stock, the 3 rail noise level would be reduced considerably. And if the flanges could be even slightly reduced, the noise level would be even lower. My opinion, but based on some measurements.

If the three- rail manufacturers would just get away from the cheap sintered "fast angle" wheels they now use, even just on their premium rolling stock, the 3 rail noise level would be reduced considerably. And if the flanges could be even slightly reduced, the noise level would be even lower. My opinion, but based on some measurements.

You're not alone.  I have a number of models with 3-rail wheels that are non-tapered, the tread appears to be straight across but they're larger than any 2-rails I have, and they have deep flanges.  The 3-rail wheels are also wider.

However, a typical 33" 2-rail wheel circumference is what, without calculating let's say it's smaller than the typical 33" 3-rail wheel.  That means if a 2-rail car and a 3-rail car are going the same mph, then the 2-rail wheel is spinning faster to go the same distance (at the same mph).  It would seem that would make the 3-rail wheels quieter, but given all the other parameters maybe not.

Also, it may be the material used, sintered vice machined metal.

I have read the above reasoning behind noise differences between 3 rail and 2 rail.

As a teenager I experienced a very noisy Lionel layout.  This was especially true of the Lionel switches.  Those dual pickup rollers and the driving wheels had one heck of a ride through the lumpity bumpity integral switch design.

There are a lot of valid points made, especially the one of speed.   From my 2-rail O-Scale experience, I am of the opinion that the main source of noise is from metal wheels.  Delrin or other plastic wheels roll so much easier and quieter than metal wheels.  So the main difference could be with metal resistance, as Delrin is a slippery material.  Next, we could also discuss noise amplification through the couplers.

On top of that, if your cars are plastic, tinplate or brass, the situation is worse.  Again, if your cars are unweighted, this also tends to amplify the noise.  Most of my cars are weighted brass or weighted wood. Boxcars and tank cars weigh 14 ounces.  Passenger cars a bit more. 

The more electrical conductivity required in your rolling stock means metal wheels.

Excellent posting...

Tom

I agree that delrin equipped cars are quieter than cars with metal wheels. (I have heard that the "downside" with delrin is that the track gets dirtier quicker.) I also agree that "hollow" cars, that is cars without loads and unweighted cars, are also noisier than cars with weights and loads. My measurements indicate that speed of the train has a major effect on the noise level. All of the above is fertile ground for changes that can reduce the noise substantially.

On real railroads, a loaded car is always quieter than an empty car....ask any brakeman.

Although all of the above impact the noise level, I believe that the "interaction" of wheels and flanges on the rail, i.e. "where the rubber meets the road", is THE major cause of excessive noise.

Hudson:

Not sure about the dirty track but the Delrin wheels get filthy quickly and it is a job to scrape it off.  It is a tacky sticky film of relatively thick muck.  I scrape mine off frequently with a dull Exacto blade used like a small putty knife.

Tom

I also hate the job of cleaning wheels, and have, in the past, used  a small motorized wire brush to clean both delrin and metal wheels. The problem with that approach is that the wheel tread then has microscopic scratches that seem to acquire gunk even faster. So now I use alcohol.

The posts from other forum members re their "noise experience" has been interesting and informative to me. It has encouraged me to check the weight of all of my freight cars, and to consider "fillers" in box cars and loads in open tops to hopefully reduce the noise. I already run my trains at somewhat lower speeds, and that has helped. I am still trying to find a way that two rail cars will operate successfully on my three  rail layout, and of course that means I will have to address switch frogs. I have not yet looked at all of my three rail equipment to determine exactly how many varieties of three rail wheels I have, but I suspect little of no standardization in this area. Nor will most of the wheel tread contours mate well with my Atlas three rail track.

If anyone can test both 2 rail and 3 rail equipment on the same layout, I would be interested in your results re noise level.

As for the basement, it looks like more area carpet and perhaps some banners for the ceiling are in my future......I was hoping to avoid this and just fix the problem at its source.

I've visited several H.O. clubs over the years and many of them prohibit plastic wheels because they seem to collect/distribute gunk. Then again, that's H.O. and O scalers' mileage may vary. Still, that stuck in my head and whenever I buy a 2-rail car that has plastic wheels I replace them with metal wheel sets.

As to the 2-rail/3-rail query, I run both at the club and the 2-rail cars seem to be quieter on the track at the club layout. I suspect that's partially related to the material/construction of the wheels -- the 3-rail wheels being die-cast with an odd contour and the 2-rail wheels being machined with a more standard contour. While the wheels seem to be the source, the car body itself transmits the noise.

I agree Matt and also about the car body transmitting noise.

Most items I've seen that we can use to fill the inside of a boxcar are either plastic or some form of resin, both probably transmit noise.

I wonder if laying a strip of padding on the inside floor of boxcars to help cut down on the noise?

Any ideas on what type of padding?

Bob, you could try carpet padding. You might also try the sound-deadening insulation material available at most home centers. A package of that would fill quite a few hollow freight cars without adding any weight.

When I modeled in HO scale I noticed that those of us in the club who operated at a more prototypical speed had much quieter trains than the "Mario Andretti" types.

Joe

Joe,

Great idea, I'm getting new carpet soon and should have some pieces left over!

Beware of foam & plastic chemical reactions! They aren't all compatible.

Quieter with two rail!

  I'm running 3rail tubular in O-gauge (Super O,O,0-27) But HO, N, & G have all been easily quieter. On the wood floor, my Lionel Porter in G can even sneak up on the dogs

•  The 3r rollers higher rpm frequencies produce a sound not found in two rail.
•  Speed seems make a big difference in running anything.
•  The isolation material in between axle, and wheels, etc. or even Delrin wheels would make a difference in vibration dampening.
•  Most 2 rail has a DC motor, no new news on the sound advantage here over one with audible ac frequencies.
• On the wheel sets of two rail, aren't they usually built to higher thrust and axle play tolerances to maintain a closer to gauge width? Less play, less noise right

I was searching for an entirely different thing and ran across something called Lizard Skin, which led me to this:

http://www.raamaudio.com/ensol...-foam-on-the-market/

If I can find a local source I'm going to give it a try.

Sound loves to bounce from flat surface to flat surface, once projected into the air of a room, creating "reverberation". You can reduce the volume in a room and also create a cleaner sound by eliminating as many flat surfaces as possible. Curtains work great in a room to corrugate the walls and stop a sound wave in its tracks. It also helps if used as skirting around a layout to keep sound from coming out from under the layout into the room. Carpeting that has a textured surface rather then smooth and the same for ceiling tiles will also help. What's nice about curtains they can be opened when not running the layout out, if your worried about hiding your pictures or display shelves. 

About all I can say is that I am building an 8'x32' 3 rail layout for our Railroad Museum here in Sioux City (www.milwauroadrailroadshops.org). I use 5/8" ply with 1x4s on 16" centers. Then we bought 4x8' sheets of homasote over the plywood. We used Midwest O scale road bed with Gargraves track and Ross switches. The homasote was screwed to the plywood and the roadbed glued to the homasote. The track was screwed to the the homasote but not in contact with the plywood. After running two trains on the two outside loops, I go home darned near deaf it is LOUD.

Dick

I would try to figure out if your screw tips may be hitting "bottom".

Or

Three words, Echo..Echo..Echo. 

With size like that I'd think about something on the underside here & there too

Light sound foam, egg crate, or rubber, stapled to the underside, even in patches.

My attempts at reducing noise were putting sound absorbing material in hollow cars.

It cut the noise quite a bit.

the center rollers make more noise transmitted to the frame and into the hollow car. None of them roll smoothly like axle ends.

I agree with the sub-roadbed and roadbed reducing most of the track noise.

If I run an engine with gons, tanks and flats, it's quiet.

If you have an iPad or iPhone, you can get Decibel 10th for free for a db meter from the app store.