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I would like to add elevated track on two sides of my 5 x 9 HO layout. The layout is somewhat typical rural Wisconsin scenery. What is the best way to make the grade changes; cookie cutter the base with risers, use foam, or is there anything new or better. When using foam do you need wood strips between the foam and roadbed. I assume you would have to in order to secure the rails to something solid.
These are pics of the ramps I am building on my 12x8 HO layout. The tops of the ramps meet on a bridge that will have a double crossover on it. The grade is 3% and the ramps are made of 5/8" plywood. I cut the curves out with a jigsaw.
The ramps sit on a base of 2" foam board. They are held in place with a screw through the ramp bases from underneath the foam. The screws go through a piece of wood before going through the foam. I can send you more pics if you need them.
Key to a successful grade for elevated track is a vertical curve, or a transition curve into the main part of the grade. You don't want any wheels contributing to the tractive effort to go light, or to be suspended entirely because the outer axles are preventing them from getting purchase on the rail heads. This isn't too much of a concern with heavy brass steamers because many of them have sprung drivers that will adapt to the changing grade and still help with the tractive effort.
An excellent way to generate the vertical curves (you need two...one into and one out of the grade) is to use half-inch plywood that is fastened securely and flush with its surrounding surfaces at the bottom. So, screw it into place well. Then, you flex it up to form your grade, and the ply will make that nice vertical curve for you. Same for the top. Make the join in the middle of the grade if you can't get a long enough piece of plywood.
In any event, you can simply cut some 1 X 2 risers and screw them in position against joists in your frame if you have that type of bench construction. You make two risers to fit after the transition curve, or more if your grade is longer than about 6 feet. The tension in the plywood along the vertical curve is such that you won't need risers there...just along the actual grade portion, and you'll want a riser every 12-16" for 1/2" plywood of any decent quality.
Bernie, I don't personally have any. I use spline roadbed which does the same thing. I'll poke around the www and see if I can find a link to some decent images showing how to anchor the plywood flush with the surface around it and then force the rest of it to form the intended grade.
-Crandell
Edit: [added] Try this site. The images are small, but if you zoom up to 125-140%, you should see that at the left, his plywood is one piece, and he uses a jigsaw to cut cookie-cutter sub roadbed and then elevates it. The pywood forms a natural transition into the grade at the bend.
For the vertical curves, I use 1/2" ply serrated on the bottom face with saw cuts about 1/8" apart and 1/4" deep for a lenght of about 4"-5" at both the entry and exit points of the grade. This helps flex the plywood quite nicely and you don't get a rough vertical transition.
Thanks to cncproadwarrior, sekector, and steamfreak. After an initial reading of your ideas, I see the potential of using something from each of you. The pictures sure helped cncproadwarrior. My first attempt at building a grade some years ago discouraged me from ever trying again. However, with an increasing amount of rolling stock I have to find a way to get as much as possible on the rails. Having a grade should help rectify the problem.
Please remember that I am a newbie and there are a lot of people here who have forgotten more about MRR that I will ever know.
Just as a FYI, I made the base of my ramps out of shims. I built them up until they were even with my 5/8" plywood and went down to nothing. So the transition from flat to ramp is silky smooth.
There will be a double crossover at the base of the ramps.
My layout is N-scale, but the technique for making grades has also been used in HO.
I'm using the cookie cutter technique but doing it entirely with foam. The sub-roadbed is 3/4" blue foam on top of another layer of 3/4" foam. The "risers" are blocks of 2" pink foam cut to the correct height and angle using a miter saw.
The resulting transition curves are nice and smooth. The method is fast, too. A new riser can be made and installed in just a minute or two. I use foam-friendly construction adhesive to glue the foam together, though I suspect plain old latex caulk would probably work as well.
The technique is not original with me. I had already decided to build my layout using this method when I found some postings about an HO layout constructed in the same way. With HO you might want to use thicker foam for the sub-roadbed.
For someone with open grid type construction, this is how mine are installed. These are 2% grades and a rotary cutter was used to shape the plywood sub-roadbed. The support "T"'s are just ripped 1x's. I latter realized that a 1x2 or a 1x4 works just as well with less labor than the "T".
The whole idea w/a Grade is the transition from the hill to the flat surface. It's not like a real train. If it's not smooth like Rex said it will give you a lot of headaches. Also, try to not have any left to right or vise versa curves at the top or bottom. Lot of derailments will take place. The longer you can make a grade the better, especially if it's over 2%.
My layout is N-scale, but the technique for making grades has also been used in HO.
I'm using the cookie cutter technique but doing it entirely with foam. The sub-roadbed is 3/4" blue foam on top of another layer of 3/4" foam. The "risers" are blocks of 2" pink foam cut to the correct height and angle using a miter saw.
The resulting transition curves are nice and smooth. The method is fast, too. A new riser can be made and installed in just a minute or two. I use foam-friendly construction adhesive to glue the foam together, though I suspect plain old latex caulk would probably work as well.
The technique is not original with me. I had already decided to build my layout using this method when I found some postings about an HO layout constructed in the same way. With HO you might want to use thicker foam for the sub-roadbed.
What you are seeing in the photo I posted is not a bridge. It is a hillside. The foam will be hidden by scenery materials -- plaster cloth, rock castings, ground cover, etc.
I am currently working on an under-over bridge and i was just wondering how to hide the side, i thought i could use a kind of stacked concrete block texture
i glued foam and then carved in the trench for the way. rough excavation with snap-off knife and then smoothed out with diamond tipped tile cutting hack saw blade, working it as if it was a file (had that laying around). the blade is long so it really smoothed peaks out and was flexible to conform to curve. filled big dips with plaster where the rail is to be directly on foam. gave it little bit more adhesive caulk when gluing road bed so it "floated" over any residual unevenness (made sure its flat by holding ruler over it).
as other said, grade transition is the key. after several tweaks i ended up with very good (IMHO) transition on extreme slope and curve (over 4% , tights up to R18) descent route and no more derailments there, even for spectrum dash-8 diving full speed down and climbing up.
on my other slope which is way more mild i screwed up the transition and even though its perfectly streight and plastic is scraping... almost done fixing it though.
I used the "cookie cutter method with 1/2 inch plywood. The beginning of my grade was at a curve, so I just traced the radius then used my jigsaw to cut the plywood. Like Crandell said it makes a nice smooth transition.
The whole idea w/a Grade is the transition from the hill to the flat surface. It's not like a real train. If it's not smooth like Rex said it will give you a lot of headaches. Also, try to not have any left to right or vise versa curves at the top or bottom. Lot of derailments will take place. The longer you can make a grade the better, especially if it's over 2%.
Not necessarily. If you can make it shorter than a trainlength, then there won't be as many problems. Of course, it might look ridiculous, but in some situations is actually is prototypical, according to Track Planning for Realistic Operation.
After reviewing the posts regarding my previous request about constructing grades, I noticed that a few builders have either laid their track directly on foam and others laid the track on roadbed which was on foam. In my thinking I have been leery of either method without first putting down a solid base (5/8 or 3/4 wood) over the foam. My concern is about securing the rails to the foam, i.e., you can't put nails or spikes into foam and expect them to remain there.
but you can put nails into cork that is glued to foam and absolutely expect them to stay there. i tried to remove glued cork in some places (installing sub-roadbed switch machines), it always came out with some pink on it. holds tight. or if one insists not to have roadbed, track can be always glued down directly (or eventually ballasted).
wood plank might work but i think good transition will be quite hard to achieve
When using foam as the sub-roadbed, the usual practice is the glue the roadbed to the foam and then glue the track to the roadbed. If not using roadbed, then the track is glued directly to the foam. Neither spikes or track nails are used.
The most popular adhesive for this purpose seems to be inexpensive latex caulk. I used the cheapest latex caulk to be found at Wal-Mart, but there are other adhesives that will work.
Push pins are used to temporarily hold the roadbed or track in place for a few hours while the caulk cures.
This method works well, and the track can usually be removed and re-used if you wish to make changes or dismantle the layout.
