Why would you want brass track for any use?  If you want 3-rail O-gauge track for outdoor use, my choice would be Atlas nickel/silver track, Henning's has had that outside the store for at least 15 years, and it's still going strong.  Brass track will give you nightmares for cleaning!

Gargraves track has a stainless steel option, but it only applies to the two outside rails. Center rail is still plated galvanize with a black coating. ??I think??    Edit Add:  stainless steel does not solder well, You may have to use some type of mechanical wire connection.    

Outside use, there is a consideration of the effect of ultraviolet light on the plastic ties.  

202 O-Gauge 3-Rail with Stainless Steel rails

In this case, I'd have to go with a proven option, I've heard of a number of outside layouts using Atlas track.  Coupled with the fact that I have personal experience with one that's been in operation for many years, Atlas would be the only way I'd go in this instance.

Do a forum search.  There was another thread discussing this in the last few weeks.

From my early HO years, what l remember, indoors!, from brass, is TARNISH!  Outdoors, l cringe.  Never understood why brass was ever used, except $$.

The G&O garden railroad uses Atlas 3-rail track.  It has worked well for over ten years.  Here is a link to the G&O Story on this forum.  NH Joe

http://ogrforum.ogaugerr.com/t.../the-gandamp-o-story

One of our club members has an outdoor O scale with Atlas track.

@Mike CT posted:

Gargraves track has a stainless steel option, but it only applies to the two outside rails. Center rail is still plated galvanize with a black coating. ??I think??    Edit Add:  stainless steel does not solder well, You may have to use some type of mechanical wire connection.    

Outside use, there is a consideration of the effect of ultraviolet light on the plastic ties.  

202 O-Gauge 3-Rail with Stainless Steel rails

The GG stainless track that I have seen (a friend used it a few years ago) is all stainless, all 3 rails, none blackened; wouldn't make sense otherwise.

www.familygardentrains.com

You almost certainly would not want to use brass rail for O gauge outdoors. That works okay for G gauge garden railways (LGB and the like), but even there you have to deal with a lot of regular track maintenance/cleaning unless you are powering the trains with battery power/radio control or running live steam. For O gauge outdoors, the two best options are, as others have noted, Atlas and GarGraves.

Yes, even in Tennessee it would not be ideal to use brass rail. Actually a good friend of mine used all LGB Track, brass color rail and it was a real problem always cleaning the track. No matter what gauge you use, go nickel silver, you can get track clips for wiring the track. Below is a picture of a friends outdoor model railroad. G gauge. 

@bigolddogs posted:

Question : Who makes 3 rail brass track for out door use?  Is there such a thing? Has anyone built a o gauge 3 rail garden layout?

Thanks

Brass oxide is non-conductive and hard to clean. You'll be cleaning your track constantly. The Atlas track has UV-protected ties and seems to hold up well from what people have told me. My own "four seasons" tests early on in San Bernardino seem to confirm this. The one caveat about outdoor O gauge is you need to be conscientious about thermal expansion/contraction of the rails. Broad curves of flex track can absorb this is you don't fasten the track down too much and allow it to "float" a little bit in some areas. Broad curves of flex don't need as much fastening. Also be aware of the thermal expansion/contraction of the mounting surface. A former colleague of mine had an outdoor layout in Las Vegas and the HDPE roadbed had some serious expansion that distorted the track mounted to it. An option would be to mount the track to ladder-style roadbed using zip ties which would allow floating while securing the track.

The float recommendation would also apply to Gargraves stainless steel track. You should also consider getting some UV-protectant spray to use on the track to further protect it.

Hope this helps some.

@bigolddogs posted:

Question : Who makes 3 rail brass track for out door use? 

I don't think anybody does.

Is there such a thing?

Probably not, since it would be a maintenance nightmare! 

Has anyone built a o gauge 3 rail garden layout?

I haven't, but lots of folks have, they just use the proper track.

Thanks

@dkdkrd posted:

Of course, that center rail is not very useful thereafter, either.

Given that he mentioned LGB, I suspect the center rail doesn't exist.

@gunrunnerjohn posted:

Given that he mentioned LGB, I suspect the center rail doesn't exist.

No, but returning to the OP's original inquiry for 3-rail brass track...   

With on-board battery power O scale operation, there is no need for the center rail....and no concern about the conductivity of oxidized brass rail.  There's a few O2R BP adherents already....maybe not with an outdoor layout.....but, then, why not?  

Again, although it has a growing following in G scale....the mostly-outdoors guys/gals...battery power will someday catch on for the smaller scales, too.  I've watched the battery technology progression at the R/C counter (our LHS) for too long to deny its potential.   Maybe not in my lifetime....

KD