I’m building a poured concrete structure on my layout, but i have no idea what would be best to use. I have heard that some sculptamold (heavily diluted) would work if you pour it into a form, but i have never seen the finished effect of this. If anyone had used this or any other method that worked out fine, please post a pic, or say what you did. Sound off
Peace
A little more information would help. Are you thinking of something like the Walthers Red Wing Milling??? http://www.walthers.com/exec/productinfo/933-3026 What scale do you work in?
One option would be to buy the mill kit and kitbash it into whatever you wanted.
A number of articles have been written about laminating styrene sheet and strip to make this kind of building (I do not have my references handy at this moment, maybe someone else can help)
If you are thinking of a large building, with repeating features, resin casting could be a possibility. MicroMark sells resin casting supplies including starter kits. You would still have to make molds from styrene or other materials.
http://www.micromark.com/COMPLETE-RESIN-CASTING-STARTER-SET,8174.html
http://www.micromark.com/html_pages/instructions/82708mrrresinart.pdf
My preference would be to kitbash the mill kit, but that is just me - I have done a lot of kitbashes. My second choice would be to scratchbuild by laminating styrene.
Sorry george. I’m using N scale and building a long bridge across a river. I want to build my own peirs so they look like i want them to, not like a mass produced plastic brick.
Peace
Try using Anchoring cement…you can get it at Home Depot or Lowes ect.
It is a real fine concrete like cement that you mix with water and you can pour it into a form or mold. There was some info in MR a few years ago.
Don’t know if this connects to what you are thinking of…
Most real poured concrete structures have rebar in them in one way or another. This would definitiely apply to a bridge span and usually to any supporting pier or abutment. The steel gives strengthso that the concrete doesn’t sheer or fracture. (That’s as much as I know about it)! [:)] If you cast a small copy you may need to give it similar strengthening.
I’m only pointing this out because I would hate you to achieve a superb casting, weather it etc and then have it fall apart due to vibration of rolling trains or movement of the layout.
Most of the time poured concrete gets modelled by making the object from plastic sheet or chunks or a wood like balsa. This is then painted or textured to achieve the result desired. There have been lots of threads here about how to do this in the past. (Haven’t got a clue how to find them). [sigh]
[8D]
I checked the websites of my local lowes and home depot, but the only thing that they have there is the Quikrete brand (50-80 lb. bags). In the store, they don’t have anchoring cement, but they do have crack proof cement, and heavy duty. If I were to get these, and reenforce them, could I use a stiff wiring (telephone, electrical, etc.), or does it have to be small tubing?
Peace
I’ve not done it myself, but I believe that for small castings you can use a product called Hydrocal. It is a plaster type product that is found in some hobby shops.
And I don’t believe that you’ll need to use any prototypical rebar reinforcement. Somehow, I just can’t envision any N scale train developing enough force to break a bridge pier.
OK, now we can get somewhere if you want to search out some reprints:
Concrete bridges:
‘Modeling Concrete Bridges with Real Cement’, MR 8/2007, Cast using Sakrete anchor-bolt cement and styrene molds. Process could be used for bridge piers as well as an entire bridge
‘Model a Concrete Viaduct’, MR 12/2003, Using styrofoam and sheet balsa
‘Building Black Bear Bridge’, MR 4/1991, 200’ long deck type arch bridge
Stone Bridges:
‘Model a Stone Viaduct’, MR 10/2002, Large masonry structure, old style
‘Adding Bridges and Water to our Pennsy Layout’, MR 8/1993, Includes stone arch bridge, small waterfall
From my database, I hope this helps
I have made a couple of bridge abutments for a ho scale deck girder bridge that will carry the track over a road.I made the abutment and wings out of bass wood then covered it lightly with scalecrete (I don’t know if it’s still available, as I did the project about 5 years ago.)
I’m looking forward to pouring some bridge abutments someday. I’m planning on building forms from styrene. I think it’ll be quite something when I strip the forms. I figure on using Hydrocal. I do wonder about using mold release. I may not need it, since I don’t plan on using the forms again. One thing I’m going to try to avoid is bubbles, as they’ll probably be pretty large and make some pretty unprototypical voids. Right now, I’m thinking that I won’t have to spend too much time on the forms, so if I screw up, I’ll just do another.
We’ll see.
Ed
I made some tunnel portals making my molds from tin foil, sheet styrene, Legos and modeling clay. Just used Plater O Paris.
I wouldn’t pour em unless you want to fool around with plaster. I think that would be the most difficult way to go.However you can get a very convincing concrete look by using either styrene sheet or mattboard such as artists use in framing work. I think styrene would be the best,plan your joints to coincide with formlines then use a good concreete color paint. Floguils Polly S has some pretty convincing colors. I just got my copy of Howard Zanes book and the old boy has done some pretty convincing concrete bridges in styrene. BILL
I just bought a bucket of anchoring cement at the local Lowes to secure my mail box pole after having backed into it. Now with the advice offered I’ll save some of it and experiment with it on the layout.
Bob
Bill’s right: why mess with pouring a plaster (etc) bridge when styrene’s inexpensive, easier to use, faster to work, and will give you something with a better scale appearance? YOu can either make a rough bridge form out of wood and them overlay it with styrene, or just build the whole thing out of slightly thicker material without a wood form (.060" or .080").
If you want texture, use rough grit sandpaper (#80 or so). I just built the Walthers large concrete coal dock, and sanded off all or most of its unrealistic pour lines. It looks much better, and even though the foughened surface isn’t to scale, it does give it a much more appealing (and unique) look.
The only reason that I’m pouring the cement by myself is that i will have repeating peirs. i think that it would be easier to go with pouring several into one mold than building each one sepperatly. I’m not worried about the top of the bridge, which i probably will use styrene, because the bottom comes first. Once i get the bottom done, then i will work on the top of the bridge.
Peace
Don’t even mess with trying to pour a concrete like wall. Build your structure and then spray it with white textured paint and then paint it the color you prefer. In HO scale, you will hardly see the stucco texture even in a concrete walled building. I have sprayed several warehouses with textured paint and then airbrushed the color that I was looking for over the textured paint. If you are try to build a structure with an external skeleton frame work, use strip plastic to simulate the external framework and once again, spray with a textured paint. I have included a couple of photos that show the effect of textured paint over sheet plastic.
[
I like those large matt walls [:D] Hadn’t thought of your technique to achieve them. Very interesting.
The thing I’ve gone on about, about concrete, before is that when you stand right up close you can see the very fine grain surface but as soon as you stand back it becomes one dull/matt blur (except for any larger lines caused by the formwork). What is happening is that the fine texture of the surface is stopping reflected light coming back to your eyes in one big lot. The millions of facets of the texture cause the reflected light to spray away from the surface in millions of directions. This means the concrete can’t look shiny… not of itself… water or other material on the face may change things.
So that matt finish is just right. [:D]
The fine textured surface - often with a slightly porous element - also means that concrete gets dirty easily… the texture gives dust and anything else somewhere to lodge/get a hold. So once I’ve achieved that nice matt finish I’ll have to work on making it dirty. [(-D]
[8D]
Lance Mindheim uses anchor bolt cement for loading docks. I have included a photo from Lances website that shows his anchor bolt cement cast loading dock. Lance uses several techniques in his structure building. The anchor bolt cement he uses comes in a 10 or 20lb plastic canister from Home Depot Check out his website at www.lancemindheim.com.
Since you indicated that you need to make bridge abutments and piers, making each one out of styrene sheet is wasteful of your time and will provide a poor result. After they are carefully glued together, yeah right, then they have to be painted to look like what they will look like if you cast them. Casting can give you as many copies as you want with just one styrene mold.
I use the big plastic signs available at HD and Lowes, i.e. no parking, for rent, etc. this is a sturdy material and is cheap compared to hobby shop prices for styrene sheet. I particularly like it for mold building.
I assemble the parts using scotch tape. No glue, no muss, no fuss. Releasing the cast from the mold is as easy as peeling off the tape. Throw it away, its cheap.
I use a thin mold release made from vaseline thinned with HD-40 or a similar light oil. Let it dry a while, then pour away with a slurry of the anchor cement or even plaster of paris. JIggle it a bit to force the bubbles out and let it set. You can make all you need in an hour or two.
The best part is they are all done, ready to place on the layout, no need to paint or coat with sandpaper or whatever. They look like real concrete because they are made from real cement. What could be easier or better?
Try it, you’ll like it!
Rusty, I was wondering if I could use a metal sheet sign (like the plastic signs you were talking about), and cut them to size. If I do this, would I have to use a peice of duct tape instead of scotch tape?
Peace