Concrete technique?

[gavino200]

I'm looking for technique guides for modeling concrete. Specifically, I'm trying to make tunnel interiors and tunnel portals.

 

I'm finding two main techniques. One is to carve joint outlines and simply paint in a concrete color. This seems like it will work for the portal. The other method I see is to leave the surface smooth, and to pencil in fake joint lines. I've also heard of using wall paper, but I'm not sure that will work for a curved round tunnel.

 

If anyone could share techniques or refer me to a good blog/site where this is discussed that would be great. 

 

Example of the "textured surface painted gray" approach.

 

[gavino200]

Also does anyone recommend any particularly accurate looking concrete paint brands/shades?

 

I found that "concrete effect paint" is a thing in home decoration. I don't know if this would work in scale.

 

https://selector.com/au/products/design-concrete-effect-paint

[gavino200]

On this site, half way down, there's a picture of a container yard. The guy made concrete joints by scoring styrene with an exacto knife and painting it. It doesn't look bad. Might work for a tunel interior.

 

http://cs.trains.com/mrr/f/11/t/134558.aspx

[gavino200]

Many people recommend using Hydracoal, and other concrete materials to mold mini concrete structures. This won't work for me.

 

Below is an example of creating texture and joint effect with paint. I'm not sure I like it. 

 

 

[Kiha66]

I did some experimentation with this for a diorama module, I used tamiya medium grey diluted into a wash over a scored surface, then very diluted india ink as a wash which I then wiped off with a paper towel.  I'm pretty happy with how it came out.

After painting with diluted medium grey.

Edited February 21, 2018 by Kiha66

[Kiha66]

And after the wash with diluted ink.

[gavino200]

6 minutes ago, Kiha66 said:

And after the wash with diluted ink.

 

 

Thanks Kiha. How would you deal with a smooth surface? Try to score it yourself? Or paint on the "texture"?

[Kiha66]

Just lightly scoring the surface should do the trick, the ink wash collects in the scores and really makes them stand out!  I did a few tests on some scrap styrene and it came out nicely enough.

[gavino200]

1 minute ago, Kiha66 said:

Just lightly scoring the surface should do the trick, the ink wash collects in the scores and really makes them stand out!  I did a few tests on some scrap styrene and it came out nicely enough.

 

I have two practice tunnel segments. I think I'll try out  a few different techniques on the rougher of the two to compare. Then I'll pick the one that works best for me, and try to get it right on the second practice segment.

 

I have that same single tunnel portal btw, I think. Woodland scenics? I was going to use it on a previous layout. But we expanded before I got a chance. 

[Kiha66]

2 minutes ago, gavino200 said:

I have that same single tunnel portal btw, I think. Woodland scenics? I was going to use it on a previous layout. But we expanded before I got a chance. 

 

Yep!  Spares from a previous building attempt years ago, so I've been using them for diorama parts.

[gavino200]

1 minute ago, Kiha66 said:

 

Yep!  Spares from a previous building attempt years ago, so I've been using them for diorama parts.

That just gave me an idea. I can used those tunnel portals to practice too.

[inobu]

Concrete is about color and texture and it depends on the material surface. 

 

Plaster material take to Woodland Scenics pigment really well but you have to learn how to dilute the pigments to get it right. In most cases its trial and error.

 

Using card stock requires a different process and you need acrylic paints to seal the paper. An airbrush comes in handy with it. In this case you need to apply light mist onto the surface to get the concrete texture. you have a base color and then light dusting. Afterward if its sealed good you can use the pigments.

 

Bottom line it varies with the material used. 

 

Don't try to get the concrete color directly. Use a series of color to get to the concrete color. Use an off white on the gray side as a base then darken areas as you move around.

 

I suggest using an airbrush because you have more control over the colors application.  You want a gravity feed brush because it takes less air to atomize the liquid media. In some cases the siphon type air brush will blow everything out of the way.  

 

You tube is the best place 

 

 

 

Inobu

 

Also joints play a key role. The color changes from joint to joint because it is different pour times. So you want your color changes or deviations to occur within the joints. Paint the concrete the same way it is poured. 

 

 

Edited February 21, 2018 by inobu

[NXCALE]

24 minutes ago, inobu said:

Concrete is about color and texture and it depends on the material surface. 

 

Plaster material take to Woodland Scenics pigment really well but you have to learn how to dilute the pigments to get it right. In most cases its trial and error.

 

Using card stock requires a different process and you need acrylic paints to seal the paper. An airbrush comes in handy with it. In this case you need to apply light mist onto the surface to get the concrete texture. you have a base color and then light dusting. Afterward if its sealed good you can use the pigments.

 

Bottom line it varies with the material used. 

 

Don't try to get the concrete color directly. Use a series of color to get to the concrete color. Use an off white on the gray side as a base then darken areas as you move around.

 

I suggest using an airbrush because you have more control over the colors application.  You want a gravity feed brush because it takes less air to atomize the liquid media. In some cases the siphon type air brush will blow everything out of the way.  

 

You tube is the best place 

 

 

 

Inobu

 

Also joints play a key role. The color changes from joint to joint because it is different pour times. So you want your color changes or deviations to occur within the joints. Paint the concrete the same way it is poured. 

 

 

I saw realistic "rocks" in layouts but I didnt have a clue of how it was done.

So many things to learn... hahaha.... thanks for the information.

[gavino200]

I'm puzzled by this technique. It's fairly common. Basically it involves painting a surface grey. Then spraying little specks of white. Followed then by specks of black. It's supposed to look like stone or concrete. Problem is, I don't think it does. I think it just looks like grey paint with speckles. Am I missing something?

 

 

[gavino200]

Adding this nice technique for creating a weathered concrete effect. Thanks to @Bubule for sharing this!