Nice catch Rick !
I totally missed that…great work Neil !!!
Well spotted indeed. Maybe a double elephant rating?? 
I even checked in my backside. No one has offered to sign it tho. 
Cheers
N
I laid out the next section of mainline last weekend. The aim was to get past the crossover, but I ended up going beyond the trestle.
I got to thinking about how to build roadbed over the trestle. It’s on a compound curve, but a constant 1% grade. After a bit of pondering I decided to start there and work backwards. I used a spline as this needs to stand alone with minimal support till the trestle happens.
The conduit had to stay in place while I build around it. I cut some blocks the same width as the centre spline + 2 spacers, then drilled a hole to fit the conduit then set them out every 600 mm. Trestle length worked out to be about 2.5m between the frame ends
Then it was sorta straightforward to build up 2 runners on each side. The baking paper is supposed to stop the spline gluing itself the the suports, fingers crossed it works…
I made sure the runners were staggered at the ends so there wouldn’t be a bunch of joins in 1 spot. Ultimate test was pulling the conduit out…
Plan is to build the trestle around this structure some time in the future. Apologies to the purists, the curved outer stringer will be seen!
Cheers
N
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Looking at the bubble on the level and foreseeing that you are working on Amtrak operations in the near future as you have left about 1/32" down on the inside edge of the curve which leads to about a scale 4% super elevation on the outside edge which is all that is needed for Amtrak on the curves.
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Cool high speed train will be available to keep running at notch 8
You’ve uncovered my plan already! There is another 3 thou available by lowering the inside stringer if I need 4.5%. That will need some careful use of the finishing chainsaw tho.
Always fear the Rooster…
Cheers
N
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Can you imagine the looks on these guys faces at Notch 8? Suspect more of a terrorised grimace… 
Cheers
N
I managed to make a bit more roadbed, will document that in a bit. My main aim was to start the crossover. I’ve started a separate thread to make it a bit easier to find.
Cheers
N
Well, Bob - where were you in '42?
General update – some winter and spring doings on the railroad.
I moved one of the shade trees mid-winter, it was planted before the railway and was too close to the yard bench.
So far so good, got a spring bud burst, lets see how it goes through the heat of summer.
The wood pile had to move as it was in the way – that led to a tidy up and general dung out. Was good to get rid of a lot of the small offcuts I was hoarding. The stack of free posts seems to have grown a bit
Nice people at a local construction site that let me raid rubbish piles to thank for that. 
As far as the railway goes, not much actual progress but have managed to tidy up some things that were nagging me. I wasn’t happy with the alignment of the trestle roadbed once I started to figure how much room I had behind it for scenery. It needed to be another 6” – 8” closer to the front of the bench.
The spline was unimpressed with my plan and refused to bend. I suppose that’s a good thing?? I cut some centre blocks out and that was enough. I got about 4” movement at the uphill end, and 10” sideways at the downhill end. You can see the original risers in the pic below.
On the subject of roadbed, I’ve had a couple of reality checks.
Sorry to say the ‘solid’ version had a bunch of stress cracks in it at the end of winter. Enough to make me pull it up. I think the knots in the timber is the main cause – it doesn’t bend evenly and the knot free sections take more stress than the harder wood.
Then a discussion at the local train show had me thinking about the screws I used in the spline. As someone pointed out, they are probably good for 10 years maximum outside without any protection. So, for better or worse – I’ve coated the top and sides of the existing splines with several coats of bitumen waterproofing. Fingers crossed!
The replacement section got stainless screws – that’ll be the way from now on.
Almost ready for first track.
Cheers
N
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maybe you should ask around a little before doing that.
i have read many stories about stainless to work itself out of the wood over the years.
maybe brass screws might do the job?
I think you are referring to issues with Stainless Steel spikes, not screws. The screws will stay put long after the wood has rotted away! Stainless Steel spikes, on the other hand, tend to push out over time. Regular steel spikes rust, and that rust causes friction to hold the spike in place, but it will eventually dissolve, so it’s a trade-off.
Looking good. I think in the long run, black roadbed will be easier to hide in the ballast.
maybe. my memory has seen better days (about half a century ago)
Thanks Jon.
Kinda obvious once I re-looked at the photos… I think I’ve got some black oil stain somewhere. Might chuck that on the new section.
Cheers
N
Hi Korm,
I’ve heard that about spikes lifting, as Jon mentioned, but not screws. It’s standard decking construction in this part of the world so hopefully no issues. I’ll keep an eye out tho.
Cheers
N
Hey guys,
For anyone who’s done a raised ladder roadbed - how did you keep ballast in place? Or did you even bother?
Closest thing I can think of is to put some windbreak cloth or similar down.
Cheers
N
Neil,
As much trouble as it may be, stretching that cloth out under the raised roadbed going from outer edge of frame work to outer edge of frame work, would provide you with a slight base for whatever scenery effect you might find need for. And a raised edge board ( set to almost same height as roadbed would contain the effect. JMHO-YMMV 
Hi Neil,
I can picture a mesh of some sort (like what you showed) to retain the ballast from falling through, and taller additional thin strips of board (?) acting as a curb for lateral retention (and as a further keeper for the mesh).
But are you not going to put in scenery? Which could handle the lateral retention to some degree?
Or, perhaps use a stronger galvanized mesh or lath sheet, placing it over the subroadbed, then extending outboard of it with a small lip, plaster over those sideways extensions (but leave the center under the track open for drainage)? That direction might perform ballast handing, and provide an attachment for future terrain (if that’s in view).
Just recreationally blabbing, fwiw…
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