Cork road-bed/underlay

[Trainman203]

I did the cork sheet under a 2' x 8' yard with no fasten down and no sealing.  Ballasted in one night and it looked beautiful.  The next day it had humped up every 3 or 4 inches about 1/2" high.  I must have put down 100 or more 3/4" wood screws to get it back down.  Then had to ballast over the screw heads.

Was able to save the yard, but needed extra just-for-men for all the more than usual gray hairs it gave me.

Broken record:    fasten down/ seal (scratch-skip) fasten down/ seal (repeat - repeat. - repeat....... Etc etc etc.)

[jward]

How about rubberized sheets for the yard, they make that, don't  they? Wouldn't the glue and ballast make it stiff in the end?

when I was in N scale I used the woodland scenic roadbed which was some sort of vinyl I believe, and spongy as well. I had no operating problems traceable to roadbed. adding ballast and glue did minimize the spongy effect so that may have had something to do with it.

for jb, in answer to your comments, I do not use cork roadbed as I handlay my track. I find that having something solid underneath the ties like pine helps the spikes grip better. my first choice for roadbed would be tru scale, but if I were using prefab track I might use cork.

the s curve problem is real. derailments do occur when the ability of the couplers to swing is exceeded by the offset of the car ends on an s curve. the formula john Armstrong proposed of using a straight between the curves of at least the length of your longest car is a rule of thumb. it will eliminate the derailment problem altogether. that said, the derailments are much more likely to occur the sharper the curve. you can for example, get away with coming out of an 18r curve into a 36r one of the opposite direction provided you keep car lengths shorter than the length of a 4 axle diesel. but an s curve of 18r without the section of straight track between the curves is asking for trouble. this problem becomes more acute as train lengths and weights increase. a long heavy train will try to stringline on these s curves even if the cars would otherwise pass through with no problems.

it is much easier to design a layout to eliminate the problem before it starts, than it is to fix it after it becomes a problem.

[jbrock27]

Thank you for your reply Jeff.

This fella, apparently has no issues with S curves, running passenger cars and 6 axle diesels, as alluded to earlier.  I am sure there are others like him out there with similar experiences.

https://www.youtube.com/watch?v=LuFjV7tm8eA

All that said, I repeat, I would not promote having them and would avoid having them if possible.  Just wanted to point out not everything written is, well, gospel, as you pointed out earlier.

[jward]

looking through his videos I could not find a passenger train or 6 axle diesel, but I did find a video of him running an rs3 and 50 foot cars through that rather wicked s curve. you can clearly see the offset between car ends, a they nd it looks like anything longer with body mount couplers would definitely derail. he is pushing the limits there. I did notice he mentioned having a bowser unit, probably a 6 axle alco/mlw, that was too big for the layout/

most passenger cars I've seen have talgo mounted couplers, or some sort of bracket that allows them extra swing. if that is true then they would probably run through there.

if you've noticed, many of the layouts in the older plan books, or sold as train sets, do not eliminate the s curves. if you were using talgo cars and engines they would probably work, but the use of higher quality cars and locomotives undoubtedly caused problems.

and yes, not everything written is gospel. even some of the nmra standards can be fudged. I often cut down tunnel portals so they just clear my tallest cars, giving then probably a quarter inch less height than the nmra guage. it gives the tight clearance effect that many places in the east once had. and it is prototypical as well, ns has 3 mainlines through the city of Pittsburgh for example but only one can handle autoracks because of clearance issues on the other lines.

even the s curve thing can be fudged somewhat. when designing a layout in anyrail, I will only put 9" of straight between curves, even though I might intend to run longer locomotives through that curve. the wider the radius the less straight is needed. the whole point is to keep the offset between cars to a manageable level that doesn't exceed the ability of the couplers to swing. 

[jbrock27]

looking through his videos I could not find a passenger train or 6 axle diesel

You did not look well enough; it is in his comments.  As I said earlier, he reports there are no issues.

if you've noticed, many of the layouts in the older plan books, or sold as train sets, do not eliminate the s curves.

Yes, I have noticed.  Anytime a "Thors Train Plan" comes up, you aptly point out they often contain S Curves.

Myself, no more talgos.  Everything either is body mounted, converted or in the process of being converted.  I am done with Transition cars as well.

Re: NMRA weight.  On board with you there.  If I am within .25 to .33 of an ounce of the standard, I am happy

Have a great Memorial Day!

[electrical whiz kid]

REF:  Large sheets of cork.

Jim; yep; those wider sheets are pretty handy for yardage, etc.  I am not comfortable with the idea of rubber sheeting-you can find it from any roofing materials distributor-probably from years of trapesing around rooftops working on wiring for HVAC applications, etc.  Slick in the winter, hot as hell in the summer.  You can't win...
Cork is really a snap to use-it doesn't creep on you when you are working with it.  That membrane stuff is about 1/16th" thick.  I would think that you would have to build it up in layers.  The only thing about cork is that it does dry out over time, and that may present a problem down the line.  Gluing cork sheets?  I would still use something like "weldwood" contact cement in securing it; not a tube adhesive-they have their place in other situations, like laying out individual trackwork.

Rich C.

[rogertra]

[quote author=jward link=topic=32167.msg238610#msg238610 date=1464528664

even the s curve thing can be fudged somewhat. when designing a layout in anyrail, I will only put 9" of straight between curves, even though I might intend to run longer locomotives through that curve. the wider the radius the less straight is needed. the whole point is to keep the offset between cars to a manageable level that doesn't exceed the ability of the couplers to swing. 
[/quote]

If I have 'S' curves, which I generally try to avoid except entering passing sidings, I do the same trick.  A one passenger car length straight placed between the curves especially as I run scale length passenger cars.  But also keep in mind, my minimum visible track radius is 36 inch or thereabouts but in staging I'll go down to 30" with no 'S' curves.  On passing sidings, I use No. 6 switches with a broad radius curve into the straight so again, that 'S' curve has never been an issue.   Even on industrial track, I'll try to get at least a three to four inch straight between the curves.  After all, on main tracks even the prototype avoid 'S' curves with no straight in between them as that's just bad engineering.


Cheers


Roger T.

[ebtnut]

I have never had any issues with Homasote.  My layout has been been stable for almost 20 years.  What I have had issues with in the past is the benchwork lumber.  In my experience, the wood you buy at your typical big box home improvement store has been aged for about 20 minutes before being shipped to the store.  Some of the stuff has turned into airplane propellers by the time it arrives.  One should probably buy up most of the wood stock you need for your benchwork and let it sit in the layout room for a month or longer to let it season in your environment. 

[electrical whiz kid]

EB;
Additionally, Try to use quarter-sawn lumber.  Most hardwoods come in that particular cut; especially firsts and seconds.  I had always used pine, but was dissatisfied with it-and the tendency for soft-woods to keep "working"  until it is sealed by paint, shellac, etc.  A spray can of "Kilz" works good, as well.
Any of the "whitewoods" such as poplar, tulip wood, cotton wood, etc., will work.
Unless you are going to a specialty house, quarter-sawn pine will be virtually non-existent.
Also, if you don't know this, make sure that you pilot-drill your screw-holes-heck, plan the thing out before you do it!

Rich C.

[rogertra]

EB;
Additionally, Try to use quarter-sawn lumber.  Most hardwoods come in that particular cut; especially firsts and seconds.  I had always used pine, but was dissatisfied with it-and the tendency for soft-woods to keep "working"  until it is sealed by paint, shellac, etc.  A spray can of "Kilz" works good, as well.
Any of the "whitewoods" such as poplar, tulip wood, cotton wood, etc., will work.
Unless you are going to a specialty house, quarter-sawn pine will be virtually non-existent.
Also, if you don't know this, make sure that you pilot-drill your screw-holes-heck, plan the thing out before you do it!

Rich C.

This time around, other than the legs, I used rejected 3/4" cabinet grade plywood for all my benchwork as recommended by Tony Koester (name dropper me).  :-)

Rejected just means there are flaws in the finish that make unsuitable for cabinetry work, it's still an excellent, soundly manufactured and flat plywood, not bowed like G1S or construction grade ply and costs just a little more the 3/4" G1S.

I had the woodshop saw it into 4" O/C strips to give 3/4" x (all most) 4" x 8' pieces for open frame benchwork.

Using open frame benchwork means you actually use very little plywood to construct your benchwork.  Just wto 8' x 4' side stringers and cross pieces every 16" cut to the width you require and you then use suitable lengths of 4" wide plywood to support your roadbed to the hight you require.

No need to paint nor seal cabinet grade ply.


Cheers



Roger T.

[electrical whiz kid]

Roger;
If you live in areas like the humid south (not up north, like us hardy souls...)  I would strongly recommend a sealer on that plywood.  Most cabinet grade plywood is put together with glue that tends to turn to glop  come apart in a moist environment.  I am not sure why they don't use aliphatic (well, maybe by now they do) resin glue (maybe they are afraid of it...) but to my knowledge they do not.
That idea is a great one, however, on it's own merit.  You are right about that AC grade ply.  It is a royal pain.

Rich C.

[rogertra]

Roger;
If you live in areas like the humid south (not up north, like us hardy souls...)  I would strongly recommend a sealer on that plywood.  Most cabinet grade plywood is put together with glue that tends to turn to glop  come apart in a moist environment.  I am not sure why they don't use aliphatic (well, maybe by now they do) resin glue (maybe they are afraid of it...) but to my knowledge they do not.
That idea is a great one, however, on it's own merit.  You are right about that AC grade ply.  It is a royal pain.

Rich C.

I'll take your word regarding living in the humid south. 

Another Hard Soul.

Roger T.

[jbrock27]

...such as poplar,...

I hate poplar trees   Some of the most useless trees found on God's green Earth!  Nice to learn that actually have some usefulness.

[electrical whiz kid]

Roger;
I spent some time in SEA-before the standard issue was boots with canvas (or whatever that was ) uppers.  Standard leather boots, given the rigors of what combat troops (I wasn't) had to do, boots practically rotted right off their feet.  A lot of guys started wearing sneakers.
Anyway,
Humidity does come into play, even here, in the lower fifty, and if not properly sealed and finished, wood can really deteriorate in that kind of environ-and I am referring to hardwoods like poplar, cottonwood, oak, etc.  Yellow pine holds up, given it's make-up.  it is hard to work with, though.
OK, enough of all of that.   The last word is that it is the modeller's cash, time, and sweat; hence, their choice.

Rich C.

[rogertra]

Roger;
I spent some time in SEA-before the standard issue was boots with canvas (or whatever that was ) uppers.  Standard leather boots, given the rigors of what combat troops (I wasn't) had to do, boots practically rotted right off their feet.  A lot of guys started wearing sneakers.
Anyway,
Humidity does come into play, even here, in the lower fifty, and if not properly sealed and finished, wood can really deteriorate in that kind of environ-and I am referring to hardwoods like poplar, cottonwood, oak, etc.  Yellow pine holds up, given it's make-up.  it is hard to work with, though.
OK, enough of all of that.   The last word is that it is the modeller's cash, time, and sweat; hence, their choice.

Rich C.

Rich.


I don't doubt any of that Rich.

I'm lucky, I live on Vancouver Island where the humidity is fairly stable all year round.  It rains a lot in the winter, joys of living in a rain forest and is fairly dry during the summer but with low humidity, unlike 'back east' and in the lower 48.  Highs of 30C (86F) are comfortable.  When I lived in Montreal, lows could get down to -40C, that's also -40F and little humidity, we had humidifiers on the furnace for us in the winter to keep the house from drying out due to the need to have the heat on for hours during the day.  Yet in the summer, the outside temperature get up to near 40C or low hundreds but around 90F is more common. Humidity in the summer is around around 90%

And yes, it really all comes down to what the modeller can afford.

Cheers

Roger T.