Back at the end of September I read an interesting blog post by Dragan Bibin about his maquette making technique. Rather than clay Bibin uses cotton wool soaked in acrylic gesso to make a sort of cotton-mache sculpture. You can see examples of his models and the resulting illustrations in his original post.
I've been dying to try this ever since. I decided to give it a try with my little snooty slug, one of the orphan characters from this week's photoshop painting experiment (bottom row, third from the left) . Here's how things went:
Bibin says that he starts with a aluminum wire armature. I generally use steal wire for my armatures because it tends to be much cheaper. I've got a few spools of it in my maquette kit at different strengths. This base is made from 16 gauge wire, about the thickness of a wire coat hanger. This stuff is pretty stiff so it makes a good base but I generally have to bend it with pliers.
Just like a clay maquette Bibin uses foil to bulk up the model before any real material is added, so I did the same. I do the same thing for my clay maquettes. I've also wrapped things in a bit of 24 gauge wire to hold the foil and base armature together.
Alright, here's where things start to diverge from what I usually do with clay. Bibin explains that the cotton and gesso need something other than metal to adhere to, so he wraps his armature in masking tape. I used drafting tape, same difference.
So I don't know about you, but I'd never heard the term "cotton wool" before I came across Bibin's post. From what I can tell it's just the British name for what cotton balls and loose medical cotton dressings are made of, which I kind of like because I don't seem to have a good word for it other than "cotton". The important thing I think is that you're using cotton that hasn't been woven or spun into anything yet.
To begin the sculpture I painted a bit of gesso I'd watered down to about white-glue consistency onto the armature, then painted a bit onto a strip of the cotton, then stuck one on the other, and then painted more gesso on until everything was soaked. Then repeat.
Incidentally, if you're following along at home might I make 3 suggestions. First, disposable gloves make this much easier and more fun. Second, have a jar of water handy to put your brush down in. If you let the gesso dry in the bristles of the brush its ruined. Third, spread a sheet of foil down on your work surface. This will keep gesso off your "clean" art table, and it won't stick to the model while it's drying. After about 30 min here's what I had:
At first the process was a bit slow. Looking back I should have added quite a bit more foil to bulk things up before I started. Having a thick layer of the cotton wasn't a big problem, but it took a while to build it up.
After the first layer I left the model out to dry over night. The next morning the surface was generally dry but I could still feel some moisture from the inside from all that building up. It's probably trapped in there forever now but I'm not worried. Up until this point I'd only been adding layers to the surface but now it was time to start adding features. I started with my slug's posh lower lip.
The features that don't have some sort of structure under them are a bit fragile when things are still wet, just like clay would be, but once things dry the model seems very durable. After adding the lip I took a break to let things dry but I really think I could have continued working just fine as long as I was careful.
On the next round I added a chin fold under the lip, and then in one last round I added eye lids and protuberances.
Bibin says in his blog post that once dry you can sand the surface. I gave this a try with a small rasp. The sanding is good for removing some of the larger bumps and uneven areas on the surface but unless you're working with some sort of power tool I wouldn't expect to use sanding to make a lot of detail. I did quite a bit of sanding on the model in the image just above but I doubt you can really tell the difference in the surface compared to the image before. You're better of smoothing things out with your fingers and extra gesso while the model is still wet.
My model is still drying but once it has I'm planning to add a bit of paint to finish things off.
Compared to modeling in clay this method does not offer nearly as much chance for detail, but because you can do it with gesso and cotton balls I think it's probably a bit more economical. I don't really think things went any faster than they might have with clay, but if I were building a large roughed in model for reference photos or the like I would certainly choose this over the clay, and I wouldn't feel bad about tossing it afterwords. Both this technique and clay are about equal when it comes to mess and cleanup.