🗿 Sculpting / Putties

Updated at 2022-11-12 22:59

You generally use putties to fill gaps and sculpt custom things.

There are essentially three types of putties; air-dry, oven-bake and chemically curing.

Air-dry putties have a limited working time before curing and are better for small things like filling gaps or fixing a broken model. A notable exception is oil clay which hardens really slowly but is still air-drying.
Oven-baked putties have effectively infinite working time as you need to bake them separately and are better for large things like creating terrain or creating whole new sculpts. These are usually polymer clay. There is also ceramic clay which is fired in a kiln.
Chemically curing putties are frequently epoxy putties where you first need to mix two different components together after which the result will harden over time. There are non-epoxy ones too like ultraviolet light -cured putty.

As a more clarifying example, if you place air-dry clay like DAS into a semi-airtight plastic bag, it won't harden. If you place mixed Green Stuff into similar bag, it will still harden.

Air-dry:           DAS, most premixed modeling compounds
Oven-baked:        Super Sculpey, FIMO
Chemically Curing: Milliput, Green Stuff, Apoxie Sculpt

to dry: a solvent evaporates; usually water or alcohol
to bake: a change in temperature triggers the hardening
to cure: a chemical reaction triggers the hardening

Air-dry putties lose volume when they dry. Remember to take that into account. The clay might also crack if it dries unevenly, so it's best to dry large air-dry installments in a cool environment.

But you can also add water to dried air-dry clay to manipulate it.
You can also cover your clay with a damp (not wet) cloth, so it dries more evenly which reduces warping and cracking.
Use texture rollers when it either wet or dry. Wait for 15 min or add more water. Otherwise it will stick to the texture roller.

You can dilute putties. Depending on the putty, you use either water, alcohol or white spirit. You might want to dilute your putty if filling small gaps.

Green Stuff:   Alcohol
Milliput:      Water or Alcohol
Super Sculpey: White Spirit
FIMO:          White Spirit

Some putties are pre-diluted to a paste for gap filling. You can further dilute them, usually with water. It makes it easy to fill gaps using a brush.

Paste Putties: Vallejo Plastic Putty (the tube), Tamiya Putty, Revell Plasto

Tip: Instead of moistening your tool or knife with water, use a 50/50 PVA-water mix; the PVA will help to harden air-dry clay quicker.

Sometimes it's worth waiting for some hardening before sculpting. Most putties take detail better after they are half way cured.

You can mix putties.

If Green Stuff feels too stiff, mix in 50% Milliput. It makes it softer to work with, making adding detail easier.
Mixing 50/50 Green Stuff and Apoxie Sculpt works great too. Less sticky but stronger; but less elastic.
You can mix Green Stuff with a bit of FIMO with great results too. The result is less hard but easier to work with as the FIMO is not baked.

Don't buy epoxy putties in ribbons. Buy your green stuff so that the components are separate and not in a ribbon. It's annoying to cut away the middle part.

Oil-based clay contains oil and wax. Oil-based clay stays malleable for long periods because the oil evaporates slowly. This also makes the clay highly re-usable.

"Plasticine" is one brand name for "oil-based clay". Other brand names are e.g. "Plastilin" and "Monster Clay".

In miniature crafts, oil-based clay can be used for:

create temporary walls for making other moulds
create temporary moulds

Oil-based clay is most prominently used in clay animation. It's important that the models stay malleable for long periods.

Practice texture sampling. If you notice a neat texture in something, make a mould out of it using a thermoplastic. Then you can replicate that texture elsewhere later.

With thermoplastic, I mean the kind of reusable plastic that can be shaped after it has been heated e.g. in warm water. I've used Polydoh but there are many brands.

The main properties of Green Stuff:

easier to do tiny details
it's sticky, so it attaches to models easily but requires lubricating your tools
it's rubbery and stretchy, so you can easily cover corners, round shapes and wires
will retain some elasticity when hard so works for things that might break like tails

Dentists and surgeons have a lot of good tools for sculpting. It might be hard to find them but Amazon might be your best bet.

Tools:

a Beale wax carver is awesome, the most of sculpting can be done with just it
a LeCron wax carver will cover sculpting straight lines
silicon shaper tools are good for organic shapes
anything works, really e.g. a tiny flattened straw is good for creating stitches

Strange names like Beale and LeCron come from the dental industry.
Some other tools in the lineup are Vehe, Zahle and Roach, but I use those less.

Sculpting benefits from tool lubrication, especially when working with Green Stuff. Otherwise, the material sticks to your fingers and tools, even silicone tools.

Water works if you have nothing else but the main problem is that you need to reapply the water frequently.
Thick hand creams like Nivea Crème works nicely. Place a small blob on the back of your hand and scrape a thin film on your tools when needed.
Vaseline works too, but you need to wash off the vaseline after sculpting or your primer won't stick as good.