Buy some drywall. Home improvement stores sell damaged or partial sheets for a few bucks.
On the smooth side draw out the pattern of the bridge side, including all the stonework. Use a hobby or utility knife to cut through the paper cover into the plaster in the patterns in the plaster. Take your time. Very carefully cut out the bridge. The plsterboard will want to crack on the stone mortar lines. Fortunately the paper on the back will keep things together.
Pick off the paper covering. Then rescribe any mortar lines. If you want to keep the stones rough, spray it with a clear varnish or oil base paint. If you want the stones more rounded and smooth, brush them with a stiff brush or a wet brush.
Then paint them as you wish.
Alternative. Plastruct sells sheets of embossed stone material. Use that or larger scale brick/concrete block for dressed stone and plastic sheet for the detail work around arches.
Dave H.
Dave H. Painted side goes up. My website : wnbranch.com
For less of a mess option, you can buy some plastic signs from Wal-Mart and glue them on the Luan structure you already have. Then get a plastic cutting tool, like a V-blade knife. Use it to scribe the lines. Any stone or block carving is going to take a while. At least with the plastic you won't have to worry about curing time catching up with you.
You could also use texture paint, which would be easier. I had some at one time and tried it for stone work but didn't like it. You might since your bridge is big. If you go with the texture paint, be sure to prime the Luan with Kills2 or something similar first.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
yes, it is big. When all is said and done the overall length will be closer to 9'. This will comprise a couple steel spans also as it crosses a river. This bridge will be 40' above water, with a ground hugging track next to it with a draw/bascule bridge. It mostly depends on what I can find that I'm happy with. This will be my big city scene, kind of a destination for most of the "goods" from the rest of the layout.
I'll have to try the drywall thing and see how it works for me. I would like to really "scratch" build this, and stay away from buying prefabricated materials like the preprinted boards. So far I have a total of $0 invested, and about two hours. I bought the luan and ripped it to 4" x 8' pieces to make I-joists to support the layout. I had a couple pieces left over, hence the 4"tall and 4" wide.
I took an even different approach. I first built the sub-structure out of the dence blue insulation board. I then covered the entire thing with home-made plaster castings also made from a home-made master. The bridge itself is about six feet long ....
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
Mark R. wrote: I took an even different approach. I first built the sub-structure out of the dence blue insulation board. I then covered the entire thing with home-made plaster castings also made from a home-made master. The bridge itself is about six feet long ....Mark.
Mark:
That sure looks like the Starrucca Viaduct.
Dave
Lackawanna Route of the Phoebe Snow
Sorry for asking this off topic question but did you use a real photo for your backdrop? If so, how did you do it?
Yes, that's a real photo between the two modelled hills. I like to back up my proto-type scenes with actual pictures from the location being modelled. The photo was actually taken standing on the top of Starrucca Viaduct ! A local photo processing chain has an option called "poster prints" - they are 2' X 3' enlargements for about $15. My entire layout was done using these !
As to making the slabs of stone facing--I recall a technique involving embossing a sheet of thin, soft styrofoam with the stone shapes. The sheet could be bent around a wall or bridge form. The embossing tool used was the empty tip of a brass pencil eraser end with the rubber eraser removed. One could reshape the soft end of the brass eraser recepticle every once and a while to change the shape of the stones. Though this idea was used to create stone facings for buildings or foundations I admit it would be tedious on a 60" bridge. Has any tried this method?
Cheers
Here is the prototype Pennsylvania Railroad (now Norfolk Southern) Stone Bridge...
http://www.davesrailpix.com/john/htm/john186.htm
Note the arches (apx. 125 years old) over the Conemaugh River, but also the two vehicular overpasses on either side of the river arches: A state highway on the left including PCC streetcars, and industrial steel mill access on the right of the photograph.
A stone arch bridge does not necessarily need to be towering over a deep valley. The pier bases here because they are surrounded by water are actually rectangular-ovals. This bridge was literally the one structure left standing after the famous 1889 Johnstown Flood.
Conemaugh Road & Traction circa 1956
Lefty