Hello,
I recently dusted off the "vintage" Walthers round coal tower that has been sitting on my "I'll get to it someday" shelf.
https://tinyurl.com/y7rwgt57
My main engine facility has a very nice Tichy coal tower so I thought I'd make this one look more like an abandoned, out-of-service coal wharf, with some, but not all, of the iron work removed.
One thing I'd like to simulate is places where the reinforcing steel, or rebar, has rusted to the point of cracking and the remaining rusty, spalled concrete surface showing through.
Coal_Concrete2 by Edmund, on Flickr
And a closer look:
Coal_Concrete_Crop by Edmund, on Flickr
And a very close look:
Coal_Concrete_Crop2 by Edmund, on Flickr
I'm sure there's ways to use decals or perhaps a "rubber stamp" kind of method to show the criss-cross rebar and mesh but that doesn't allow for the chunks of missing concrete and rough surface of the aggregate behind.
Coal_Concrete by Edmund, on Flickr
I don't recall seeing any articles in the Modeling press. Maybe someone is familiar with a method or has seen something like this modeled. I'm sure the military modelers might have something, too.
Google returned discussions about paint color or mostly, real-world spalling concrete even though I used key words, scale, model, simulate, old, concrete in different combinations.
Any input would be appreciated. This would make a nice technique for old retaining walls, too.
Thank You, Ed
Not that I've ever tried these techniques, but a cut-off disc and/or a cutting burr in a motor tool could give you a start on spalling concrete, and a few applications of solvent-type cement to some of those same areas might help.
You could drill holes where walkways, ladders, and the loco servicing hardware had been, then insert stubs of wire to represent the bolts/anchors with which such items would have been attached.
Patches of exposed rebar would be a bit more work, but after digging out the area with the aforementioned tools, a drill bit and some wire could put it in place, and you could then apply filler over the area where the ends of the wire had been inserted.
Distinct and well-defined rust stains can be done with paint and a suitably-sized brush, while wider, over-all rust staining is better accomplished using oil-based artists' pastels.
For the coal-darkened areas, washes of dilute India ink or applications of black/dark grey pastels should work well.
When I made moulds for casting bridge piers and abutments, I used files and chisel-type blades in my X-Acto to create the impression of form boards in the .060" sheet styrene, but it's barely noticeable in the plaster castings....
Wayne
A thin coat of Hydrocal might work. Tint the Hydrocal to get the color. Apply it over a grid of wire, pre-weathered with rust for the rebar. Then, you can chip away at the Hydrocal to get the crumbling cement look. Use more rust stain, very thin, to get the illusion of rust running down from the rebar.
It takes an iron man to play with a toy iron horse.
I am finishing a model of Walthers Sub station that has a chain link fence around it. My idea would be to cut out a section of the plaster, then cut out a section of chain link fencing to match, paint it rust color and glue it in the recess you made in the plaster. You would have to orient the mesh to simulate the wire reinforcing mesh.
Sounds like a good idea, I may try it on some buildings.
Joe
www.textures.com (formerly cgtextures.com) has a number of concrete textures available for download. You could print them and past them or create custom decals and use those. In general, texture files can be placed together to make larger areas, or resized to do the same.
This should work pretty well if the building is some distance from the layout edge and/or partially hidden by foreground buildings.
An interesting challenge and I am glad the OP showed photos of the damaged areas from different distances, because I think most methods of capturing this look would tend to overdo it and make the rebar and chipped concrete too obvious -- too much like the close up photo whereas we view our models from a considerably longer distance.
From a distance it is more a matter of color and overall texture than actual "3D" details to be modeled. The rusted rebar looks almost like a rubber stamp did it on the distance photo. Taking some mesh, dipping it into rust colored acrylic paint, dabbing that onto a paper towel, and then almost "drybrush stamping" it onto the plastic surface might capture the look of explosed rebar.
Another thought would be to cement very small plastic strips in the pattern of the rebar, then attack them with a sprue nipper to remove all but the most ghostly outline of the rebar. That is how I model the torched off remains of steel structural shapes welded onto steel flatcar decks.
The rough texture surrounding it? Actually pretty shallow. Perhaps sandpapering the surface, followed by Dullcote, followed by a dusting of cement colored weathering powders, followed by more Dullcote. I'd do that first then add the rebar simulation.
Dave Nelson
Thank you, everyone, for some great ideas to try out.
You have some excellent ideas, Wayne, with the drilled holes and "stubs" of burned off hardware. In a few places I might go one step further and place a few "Nut-bolt-washer" moldings with the remains of an angle bracket. Maybe a few eyebolts, too.
I have a pretty good selection of rotary cutter bits that I'll play with. Good choice, and the holes with fine wire threaded through might just give me the rebar-look I'm after.
I'm not sure if the hydrocal will adhere that well to the plastic but I get the idea. I think a dusting of heavy-bodied primer might do the trick, too, Mr. Beasley. I'm sure familiar with Textures.com (the third photo above is from them ).
https://www.textures.com/category/bunker-wall/1914
I like the idea of the mesh, Joe. I think that bridal-veil stuff is called tulle, or something (pronounced tool). That has a good look to it. Like Dave suggests, maybe dabbed in paint and lightly touched to the surface?
You make a good point about using the artistic approach and not over-doing it, Dave. I like the idea of the weathering powders, too.
All good stuff.
I was mulling over some ideas, too, and I'm going to see what effect using the Paasche "Air-Erasor" will have on the plastic. I'm thinking maybe gouge out some sections with a ball cutter as Wayne suggests, then tape a piece of wire screen in place and sand blast over it? Or just sand blast (unfortunately, glass bead is the medium I have most of but I also have some very fine white ballast I have no other use for so I'll try that). From my past experience with sandblasting, I'm not sure ti will really remove soft plastic but heat it and move it around. I'll find out in a few days when I go out to the "big shop" to do the blasting.
Right now the spot I have chosen for the abandoned coal tower is close to the aisle so I have to be careful with the final look. I have some left-over parts from a Walthers grain silo to test the methods on. I'll report back with my results as I learn.
Thanks again, Ed
Ed,
Do a search on youtube of tank and military modelers. They have this covered and there are some very nice how-tos out there.
Guy
see stuff at: the Willoughby Line Site
Thanks Guy,
I have seen some great bombed-out concrete from the military side of the modeling hobby. I tried a few more keywords in my searches but still a good percentage of the sites found show me real-world bomb shelters, bunker busters and failed concrete structures. "Modeling" in the building trades seems to relate to simulating failure to predict damage to concrete structures.
I used the key words "hobby diorama" and that seemed to bring in more results.
Scale Modeler magazine seems to have a bit of information but I'm still digging. Much of the controversy is over paint colors rather than decay and rusted rebar.