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Carving rocks from foam

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Carving rocks from foam
Posted by Andy110675 on Monday, December 11, 2017 1:47 PM

Right, so far i am in the process of attempting to carve rock faces from blue foam.I have tried using moulds from woodland scenics but in all honesty i prefer the foam approach.Is there a certain way to tackle this or do you just hack the foam out and then use a fine file to show detail.I dont really see as it is possible to follow a photo of a rock face and reproduce it into a scale version without taking years.So do i just go with my eye and say yes that looks good or are there any alternatives.

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Posted by selector on Monday, December 11, 2017 1:54 PM

It's very time-consuming, but the best way with foam is to make initial rough and broad shaping cuts with a butcher knife or with a foam-cutting hot knife.  Then, you refine the surface and it's rock-like look using scalpels, utility knives, hobby knives, and the like...and this is where it eats your time like cookies 'n milk.

I would not use a file because files and steel brushes leave too many parallel grooves, rendering an unrealistic look.  My opinion.

 

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Posted by RR_Mel on Monday, December 11, 2017 2:15 PM

Using Hydrocal with molds works best for me.  Much easier and faster too.  The Hydrocal takes stains very well and I find that Hydrocal rocks are easy to carve.
 
 
 
Hydrocal cab be a bit messy but it works good for me.
 
 
The Hydrocal excepts stains very good.
 
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
 
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Posted by mbinsewi on Monday, December 11, 2017 3:05 PM

I used Selector's method.  You can check out my pictures in the links below my name.  Every rock face is carved from pink foam, and painted.  No plaster involved.

Mike.

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Posted by BATMAN on Monday, December 11, 2017 3:20 PM

I use everything and anything to carve with. Knives (electric, bread, steak) chisels (stab and break), scrapers, fingers, rasp, you name it. Don't be fussy, just fly at it. I dab on bits of dap here and there to rough it up a bit before I paint. 

Brent

It's not the age honey, it's the mileage.

https://www.youtube.com/user/BATTRAIN1

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Posted by selector on Monday, December 11, 2017 4:48 PM

Very nice, Brent.  I am planning a couple of rock cuts on my current build, about two weeks away or so.  Turning over ideas in my mind all the time.

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Posted by BATMAN on Monday, December 11, 2017 6:21 PM

Thanks, Crandell.

One thing I learned along the way was about painting the foam. The first ones I did I just slathered on the grey paint and went from there. Of course, it was after that I read a good article on how to paint Rocky Mountain granite. It said to start with an absence of colour such as a black or very dark brown, I chose the cheapo brown from Walmart. I then hit it with the Walmart grey and about a dozen of their $2.00 bottles of the acrylics from the art dept that I dry brushed on.

Puting the dark brown on first just gave it a little something extra as far as giving it a richer look.

I should take a newer pic as I have since painted the track and put down ballast.

  

 

Brent

It's not the age honey, it's the mileage.

https://www.youtube.com/user/BATTRAIN1

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Posted by Andy110675 on Tuesday, December 12, 2017 3:24 AM

All your rock formations are making me jealous lol.I think i will have a practice on some foam first and mess about with some paints.The last thing i want to do is carve some nice rocks then mess them up with poor colouring.I have tried the moulds and find my self repeating the same pattern through out.

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Posted by BATMAN on Tuesday, December 12, 2017 10:32 AM

Andy, foam rock doesn't need practice as random is good. After you get the basic rock colour down just fly at it with some dry brushing. One thing about painting, you can just add more if you don't like something. 

The more numbers/variety of colours the better it will look. Don't be fussy, it is not paint by numbers.

After I had the paint done, I sprayed some different washes over them as well.

Brent

It's not the age honey, it's the mileage.

https://www.youtube.com/user/BATTRAIN1

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Posted by Medina1128 on Tuesday, December 12, 2017 10:45 AM

I've used both the carved foam and rock molds from Woodland Scenics methods with plaster of Paris. I actually prefer the rock molds. I have different molds and even break up some of the larger ones so it doesn't look like they're all from the same mold. Turning them upside down or at angles works, too. I also use the Apple Barrel acrylics from Walmart. 

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Posted by Andy110675 on Tuesday, December 12, 2017 12:27 PM

Well i have made a start on my rocks and so far so good but its taking me hours to complete a short distance but i am enjoying it.Here is a quick vid but in all honesty the camera doesnt do it much justice.

https://www.youtube.com/watch?v=8K8kLH_tkH0&feature=youtu.be 

 

 

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Posted by mbinsewi on Tuesday, December 12, 2017 2:29 PM

I think your off to a great start!  Once you start painting and highlighting, your cliffs will "pop" with realizm.

Even after you start the coloring process, if something doesn't look right, or too uniform, or too repetive, start hacking away some more.

Is there any specific area your modeling? or just looking for rock cliffs?  The reason I ask, there are lots of Google images, under rock cliffs, that would fit well with the layered structure of the foam sheets.

Lookin good!

Mike.

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Posted by kasskaboose on Tuesday, December 12, 2017 9:57 PM

Making rocks in foam is fun.  I did that on the layout and plan on doing it again.  As other said, finding rock colors and formations of the region you plan on modeling is critical.  Once done with research, then get the cheap paint.  

Don't be afraid to repeat rock colors or formations at different parts of the layout.  Heck, you can even change the angle of the rocks slightly so no one notices the differences.

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Posted by Andy110675 on Wednesday, December 13, 2017 1:57 AM

Thanks for the comments,I am unsure as to what colour to do them but they do resemble the teracotta rock faces found in the states but i think one colour all over is abit bland what do you think.

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Posted by hon30critter on Wednesday, December 13, 2017 2:13 AM

Andy110675
i think one colour all over is abit bland

Most rocks are pretty much the same colour throughout, but it's the shadows and highlights that really give you a sense of depth and texture. Things like an India Ink wash will darken the crevices, and dry brushing the high spots with a wee bit of white will give your rock much more depth even if you do use just one colour.

Dave

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Posted by Andy110675 on Wednesday, December 13, 2017 2:18 AM

Do you think a dark grey base will work then dry brush over the faces of the rock with light grey and finally highlight with white.

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Posted by hon30critter on Wednesday, December 13, 2017 2:39 AM

Andy110675
Do you think a dark grey base will work then dry brush over the faces of the rock with light grey and finally highlight with white.

That will work, but I wouldn't go too dark on the first coat of grey. I do recommend using two or three shades of grey. If you have the three colours open all at the same time you can blend the colours when they are still wet to make the changes in rock colour more subtle. Using an India Ink wash, or a wash of heavily diluted black paint after the primary colours have dried will further add to the depth. The wash will accumulate in the crevices which is where you want the dark lines. If the base colour is too dark the wash effect will not work as well. Be careful with dry brushing the white on the high points. It shouldn't stand out.

Remember, the nice thing about paint is that if you don't like it, just paint over it and start again.

Dave

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Posted by Andy110675 on Wednesday, December 13, 2017 3:22 AM

Decided to go with a light grey base coat followed by the diluted black wash.I will then highlite the faces of the rocks with another shade of grey and finally finish with the white,does that sound like a plan.Big Smile

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Posted by mbinsewi on Wednesday, December 13, 2017 6:16 AM

Sounds great Andy, you'll never know until you try it.  Anxious to see the results.

Mike.

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Posted by Andy110675 on Wednesday, December 13, 2017 11:17 AM

Thanks Mike and everyone else for your comments.I have spent another 10 hrs on the rocks seen in the video and they are looking very realistic and i am happy with the results but not finished on those yet would like to put some hairline cracks in the face to resemble slabs of loose rock.p.s love the realism and colours of your rock faces Brent & Mel

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Posted by Track fiddler on Wednesday, December 13, 2017 3:41 PM

I have to tell you I love making rocks out of foam. Every one you make is always different. 

I'm the kind of guy that likes to sit at my work bench and do something crafty at night. I rarely watch TV. Some nights I'm tired from work and don't want to work on something intricate, tedious or anything that takes a lot of thought. It is those nights I make rocks out of foam and paint them. I have two shopping bags full of them.

My brother who is also a Model Railroader makes his rocks out of plaster in molds. I sent him pictures of my foam rocks and he didn't believe that they were not made from plaster molds. So I had to send him the same picture with one inverted so he could see they were pink foam. Here are some pictures of four of them I grabbed out of the top of the bag.

I'm now thinking of simplifying things on my layout process doing shells. Then just adding the rocks I make where I want rocks.

Happy modeling   Track Fiddler

PS  Through trial and error, what I have found, it's all in the diluted paint technique that brings out the detail in foam rocks. I'd be more then willing to share if anyone's interested in that technique Wink

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Posted by Andy110675 on Thursday, December 14, 2017 3:04 AM

very good well done so far my rock face is about 7ft long standing at about 10" only another 16ft to goBig Smile

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Posted by Andy110675 on Thursday, December 14, 2017 1:55 PM

Hi Mike sorry for not answering sooner.Not really anywhere in specific just so long as they look like cliff faces really.Your right about google images it has given me some good ideas.At present my rock faces are about 18 inch tall and it really is taking for ever.The problem im having is where to stop the rock faces should i just taper them down to nothing or do ijust stop the face at the same height.

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Posted by Track fiddler on Thursday, December 14, 2017 5:32 PM

No bites I'll tell you anyway. You start by painting your foam white. 8 parts water 1 part cheap white hobby paint from Walmart. Dry it with a hair dryer and do it again for an equivalent of two base coats of diluted white 8 to1. Take the same cheap black hobby paint from Walmart. Dilute 16 to 1 with water. Coat The Rock and dry with the hair dryer. The Pigmant will soak in and dry highlighting the cracks and fine detail. Take your dominant Rock color mix 12 to 1. Dry brush your brush and use the side of the brush to coat the high points of the rock your brush touches. After that dries with the hair dryer  Take your lightest color and do the same.

Wallah!      Track Fiddler

PS.    The trick is watered down washes so you don't lose your detail. Take notes in what you do. This I learned the hard way.  Especially color washing foam bridge portals. Do them at the same time. The next day you won't remember what you did. They won't match and it turns into a nightmare.

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Posted by Track fiddler on Thursday, December 14, 2017 6:53 PM

You can see what I mean here. I worked so hard on these (edit) tunnel portals. It was a shame my paint was too thick and I lost my detail. I will still use them but they could have been better with paint washes that were thin and diluted preserving detail.

My paint was too thick. I hope you can see what I'm relaying. I Hope you see what I'm getting at here.

Big Smile Track Fiddler

PS   Paint can take you or break you

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Posted by Andy110675 on Friday, December 15, 2017 2:48 AM

I dont see anything wrong with those bridge portals is there somthing im missing.Is it really necessary to paint the rocks first with coats of white and if so what is the purpose for it,i would of thought you could just base coat the rocks in light grey then diluted black and then dry brush the faces and white highlite the tops.Smile Looking at the bridge portals again the only problem i see is the black lines where the mortar would be is a bit thick and dark.

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Posted by Andy110675 on Friday, December 15, 2017 3:23 AM

Just looked through your photos Mike wouldnt work before for some reason but anyway your scenery is making me jealous some of you guys on here must have spent years on your layouts i take my hat of to you.Bow

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Posted by BroadwayLion on Saturday, December 16, 2017 10:10 AM

I suppose you *could* make rocks out of foam.  I prefer to go out to the back yard and find my own rocks.

 

 

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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Posted by crzink on Saturday, December 23, 2017 8:47 PM

So, below is a shot of the former "cliffs" of Provo, Ut. above the steel mill that was on the Texas Western Model Railroad Club's old layout.  Almost two feet of stacked 2" pink foam, about 8' long and only about 2-1/2" thick at the top.  On the right side you can see where the lighter colored scenery from the opposite side of the foam wraps around.  (The opposite side represented high sandstone bluffs like found in the 4 Corners area of the southwest.  It was carved in the same manner, with like tools.)

The Provo cliffs were carved mostly with small blade to wide blade screwdrivers, a dinner fork that had the tines spread out, a wood rasp, and a fine bristled small steel brush.

Pueblo Steel Mountain

The idea here was to replicate the limestone formations making up the Wasatch Mountains east of Provo and SLC.  These limestones tend to be blocky and massive, but do have thin partings of shales and some sandstones in them.  I carved the blocky parts of the limestones mostly with the screwdriver because it will rip out chunks of foam and leave a "rock like" surface, roughed out the sandstone layers and shale layers with the dinner fork because I wanted to represent distinct thin, and finished the shale layers with the fine bristle steel brush because it gave the very finely layered look typical of shale formations.

The area off to the left, behind the building, represents a major fault and break in formations, with an "iron formation" intrusion.

The vertical "cracking" or "faulting" was again carved with screwdrivers, depending on how wide the fault was to be.

A custom mixed grey latex paint wash was used as a base coat, then the formations were defined with darker greys up to "not quite" blacks.  Certain places were intended to "weep" moisture, so those got a little matte medium to give a "wet" appearance.  Bushes, grass, and weeds were thrown on as appropriate from various types of ground foam. 

As BATMAN said, it's easy, and proved to be fun.

CRZ

COO, TWMRC

twmrc.org

 

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Posted by Andy110675 on Monday, December 25, 2017 3:38 AM

Thanks for that they do look great very detailed and good colouring.Im strugling with the colour but i have gone with a grey basecoat and i intend on using a black wash but im worried it will ruin the work i have done so far.

                           Merry Christmas.Gift

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