Large Scale Central

Batch of turnouts for Stage 2

Track and Trestles
#1

Hi all, Since the next portion of the 1:22.5 RhB will be on the ground (as opposed to on elevated benchwork) the turnouts will be built on sheets of 6mm PVC.

Left to right: bare shiny PVC, PVC roughed with sandpaper, glued paper template, ties glued to template

There will be modifications to the process used on the PT ply base. I’m sure I’ll have to pre-drill every spike hole to 1.05mm Once the Llagas Code215 rail is soldered and spiked down it should be nice and stable.

That’s where the seven turnouts will be used. The only reason I start early this year, in the winter I need that workbench for a wax table. Priorities! :wink: :slight_smile: :wink:

#2

Why the paper? Won’t that deteriorate in the weather?

#3

Probably the same reason I glue the paper down. Its a template for the ties. I use Templot to generate my track templates, and, while its a pretty steep learning curve, it does generate exactly the turnout you need, so you can make the track layout you want.

Wandered off subject there, sorry!

#4

Just be careful next time Bob , or we’ll report you to the site owner .

Mike

#5

Bob McCown said:
Probably the same reason I glue the paper down. Its a template for the ties. I use Templot to generate my track templates, and, while its a pretty steep learning curve, it does generate exactly the turnout you need, so you can make the track layout you want. Wandered off subject there, sorry!

Yes, that is the template for the turnouts. I draw mine with CADrail

the frog is 12º or approx #4.5

#6

That makes sense.

What happens after the first rain storm? Or don’t you worry about that? Doesn’t the paper get in the way of a bond between the ties and the plexiglass?

I’m trying to sort this out because I want to build my turnouts. The storebought ones are too spendy.

SteveF

#7

Steve ,
I think you will find that plexiglass won’t work either . PVC certainly is not long term stable .
The points that I make are stand alone , no backing except the ground or ballast they stand on . This allows drainage to occur . PVC or Plexiglass sheet warp , hold water . and in the worst case , the water freezes and knocks the crap out of your handiwork .
Yes , a good level base is fine for building on , even for gluing the plan on , but leaving it in place under the trackwork ? Not recommended .
Tried it , ruined it , regretted it .
Mike

#8
Steve Featherkile said:
That makes sense.

What happens after the first rain storm? Or don’t you worry about that? Doesn’t the paper get in the way of a bond between the ties and the plexiglass?

I’m trying to sort this out because I want to build my turnouts. The storebought ones are too spendy.

SteveF


Steve,

The first turnout I built was on PT plywood. Left it out in snow, rain, freeze, thaw, very hot summer weather and other than weathering that turnout is the same as several years ago when I first put it out there. Spikes didn’t move, rail is in gauge etc. etc. Can’t ask for more.

Since I don’t want to use PT ply on the ground, I got a test piece of PVC (only 4mm thick) to try out the adhesives. Tested again and the results are excellent.

I’m using Weldbond for adhesive and the stuff penetrates right through the paper since I put down the ties right after I glue the template. Generous application of glue!
In addition to that the spikes penetrate more than 1/8" into the PVC. And the 6mm (1/4") PVC makes a very good base, drainage holes (if required) are a breeze, mounting throw mechanisms is not a problem.

Yes, it depends on the climate, tests tell me it works in our climate. :wink: Since I like things as maintenance free as possible, I test first.

#9

Actually PT Ply is EXCELLENT on the ground, specially if you keep it covered in ballast and moderately damp…UV seems to be a more damaging influence than wet, water, ice or snow…Gary B has stuff on plywood down going on what? 10 years now Gary?

#10

Bart,

I’ve had a bunch of PT ply pieces outside lying flat, didn’t like the warp in the stuff after a few months. :wink:

Could be we send all the good PT to the USA and we’re stuck with the second grade. :smiley:

#11

Yes thats the best deal , maintenance free , HJ .
Its my whole objective with outside trains , run em for fun , not have a side job doing maintaince .
Its enough maintaince now with picking all the fallen leaves off the layout .
But 73 degrees here in Nov is some swell train running conditions .

#12
Hans-Joerg Mueller said:
Bart,

I’ve had a bunch of PT ply pieces outside lying flat, didn’t like the warp in the stuff after a few months. :wink:

Could be we send all the good PT to the USA and we’re stuck with the second grade. :smiley:


Yes but was it in the sunlight? UV Thats what causes it to warp and delaminate…My current yard was one the ground and under ballast for close to two years before I I pulled it out…pressure washed it…and mounted it on 2x4 frames…it looked just like new after the warshin’…

#13

Bart ,
Your system allows the water to escape ,if it is left to itself on plexiglass or pvc , it beads , and does not run off . The beads get trapped under the rail , and lift it when they freeze . I would strongly advise against any method that does not keep the track itself out of contact with a solid base other than wood–which flexes and allows non damaging movement , and no stress build up . The ideal , not surprisingly , is ballast . Or have the big rail people had it wrong all this time ?

#14

PT plywood if left to dry out (I never have found anything but saturated stuff at the big box store) will curl up like a wavy potato chip. Keep the stuff moist, like it stays in the ground around here (90% clay) and it stays flat, especially when you load it down with ballast. In cases where the stuff has dried up before I got a chance to use it, I just soak it down good on both sides and weight it with some cement blocks till it returns flat and keep it wet thereafter till it’s ready to plant in the ground. I have one section I will be pulling up soon because the ties have gone South (in the days before I used 100% PT for ties) and when I do I’ll post some photo’s. Said piece has been in the ground for 10 years.

#15

Gary,

With what little rain we get here in the summer - if it isn’t irrigated, it will be brown! - PT just doesn’t stay wet.
Which means getting rid of water will be a “minor” problem.

#16

Interesting discussion.

I would add that UV does not cause warpage, just deterioration. I can’t think of what would cause PVC to warp, it’s used outside all the time.

Always wondered why some people have great luck with pt wood and others get warps. The theory of it staying moist would really make sense, drying always causes warping as the wood will become less flexible as it becomes dryer, and shrinks. Shrinkage is rarely perfectly linear.

I learn something every day. By the way, my track is all free-floating, but it never freezes here, and little rain, so no need to try to fix it permanently.

Regards, Greg

#17

Greg,

Rest assured I’ll post how well “things” behave under operating conditions. :wink: :slight_smile:

Installing drip irrigation at the turnouts wasn’t in the plan, but that could be a way around warping the PT. BTW my source of PVC produces “a few” items that have to stand up to the Okanagan climate, he thought it was a very good choice for stability and durability.

#18

Greg ,
I am not a chemist , it’s just that PVC warps when I have tried it . I know why , but not how—the track/sleepers shade part of it so it is not so hot , even with a thin layer of ballast on . The warp centre follows the track centre .
Perspex , plexiglass , whatever , is affected by the sun . Apart from yellowing , it can bend quite a bit , maybe due to partial shading .
The other factor that is generally ignored in all this talk on track supports is the inevitable deposition of water from the ground onto the underside of the medium .This is especially true overnight , and the phenomenom is the basis of getting water in a desertif you are ever stuck . Anyway ,this makes one side wet and cool , surface heating expands the upper surface , so it forces a bend .
It happens , I have seen it , so I don’t use plastics, it’s that simple . Some of them bend free standing , but not much ,so it’s generally safe to make buildings from it .
Mike

#19

Bolt some angle or channel iron gussets under your plywood. Prime the heck out of it first. That’ll stop the warping.

#20

Guys,

Thanks for the tips. I’ll let you know how the PVC works out. :wink: