Tonight I was rocking out in the basement!
No, seriously. I was working on the first section of our 16 foot long waterfront which will likely end up being mostly rocks.
And I figured since I was in the rock mood tonight I would crank up some rock music! So for tonight’s rock session I jammed out to some Shinedown and a little AC/DC mixed in between.
See, told you I was rocking it!
If you listen to this week’s podcast you’ll hear about the different ways we’ve made our rocks on the layout and since I have so much fun making rocks (it’s seriously one of my favorite things to do) I thought I would share one of the methods!
Making Custom Rocks with Plaster of Paris
This is one of my favorite ways to create custom rocks on the layout. It’s the most fun, messy, and it allows for a lot of flexibility when compared to rock molds. Don’t get me wrong, rock molds are great for cranking out rocks fast, but it can become repetitive if you don’t have enough variety in molds.
Making custom rocks from plaster of paris is also a very affordable way to put a lot of rocks down on your diorama or layout. You can pick up a big container of plaster of paris at your local big box home improvement store for a fraction of what hydrocal will cost at the hobby/craft stores.
Really all you’ll need for this is:
- Plaster of Paris
- Water
- Mixing Bowl
- Small Spatulas
- Exacto Knife
- India Ink Wash
- Brushes
This process is really limited only by your knowledge of rocks and what they should look like or how they appear in nature. But this isn’t too hard since we have the world of information and photos at our fingertips. So if for some reason you can’t get out to check out some rocks in the area you’re modeling, you can fire up the old Google machine and search for rock formations in the region of your layout. You can also check out Google Maps and Street View to see if you can scope out any rock formations that fancy your tastes.
Let’s Get Started!
To begin, we mix the plaster of paris and water in our mixing bowl. I’m sorry ahead of time that I don’t have any really scientific methods or exact measurements for the right plaster/water ratio but I’m just not that kind of way… My technique for this is quite simple. Mix the plaster and water until it resembles marshmallow fluff. PLEASE DO NOT TASTE the plaster at this point! Just because it has the texture of delicious marshmallow fluff doesn’t mean it’s edible. Because it’s not.
Once you have achieved this texture (slightly runnier than peanut butter) you have to work a little quicker to begin applying it to your foam or layout base. This part is more about getting thick globs onto the area you want rocks and quickly shaping them into the general size/shape that you want the rocks to be. We’ll fine tune the look and feel of the rock faces later.
As you get the plaster down and cover the desired area it will begin to set relatively fast. Once it becomes a little more like a clay texture you can use your small spatulas to begin to carve, press, and scrape ledges, crevices, large formations and shear faces into the rocks. This is the first part of the fine-tuning part of the rocks and is the point in which your rocks will begin to look more like rocks and less like the Stay-Puft Man from Ghostbusters.
Adding the details
Now that you’re satisfied with the shapes of your rocks you’ll want to add some deeper crevices and cracks to them. For this I like to use an old xacto knife. I have two of the same sets of xacto knives, one set is just an older set that I’ve turned into the muck & junk knife set for things like this.
I just use my imagination and a little randomness when applying cracks to my rocks. If there is a place in the rock formations that has a really deep area or a big flat rock face that needs broken up with a crack or defect, I’ll use my knife to etch some features in.
The one area that I like to make sure I hit with the knife is deep crevices that I want to look darker and I scrape a little more plaster out.
All of this work might look a little flat or featureless up to this point, but once you apply the india ink wash, all your work will pop!
Time for some color!
This is my favorite part because it brings all of your work out. And it’s relatively simple.
I just use my lighter india ink wash and my designated ink wash brush (please tell me that you have a different brush for washes, pastels, and paints) and apply the ink wash from top to bottom.
I find that it looks good to blot it on where the cracks and deep spots are and let it flow downhill into all of the nooks. Make sure to cover the rocks in a layer of ink wash to start.
Let that first layer dry and from here it’s up to you to determine the direction you want to take with your rocks. If you want to have a gray rock color like we do, I would add a couple more applications of lighter ink wash to add contrast. You don’t have to add the wash to the entire rock area for each layer, but as you go on, just add more wash to the areas where you want more contrast.
If you’re going for a different rock type, simply use other washes and weathering pigments to obtain the right color to match the type of rock you desire.
This will get you the base color of the rock and we think that it makes the most realistic rock style. The only remaining thing to do is a little weathering to add the appearance of dirt and age.
This last step will depend on your scene and can vary greatly from one layout to the next. Since our rocks are mainly along a waterfront, we’ll add a little bit of brown chalk dust and sprinkle some dirt on the top ledges of the rocks. The rocks may also get a little bit of plant life added to the cracks and areas where more dirt has accumulated.
But the final weathering and addition of foliage is really just as freestyle as the prior steps and will end up being uniquely yours once finished. The main thing I have to recommend is to just check out what rock faces and major rock outcroppings look like in real-life, and try to mimic what you see to the best of your ability.
Nothing is better to learn from when researching your scenery than what mother nature’s made for us!
Do you have a different rock modeling technique99? We want to hear about it in the comments!
