Wednesday, August 5, 2009

Sculpting 102: Putty

I liked the look of the last post so much that I've decided to start each post tutorial with a finished fig that I've sculpted on. The pic above is of the exact same basic Assault on Black Reach Ork Boy. The one on the left is unmodified and straight off the sprue. The one on the right is what happens when I start feeling "creative". You'll be seeing the guy on the right quite a bit as we progress. He is my demonstration piece for several of the techniques I'll be covering. Someday I may even paint him...

Now if you've spent any time in a hobby store or surfing the net regarding sculpting, you've heard of Green Stuff. This is the bread and butter of the sculpting world, also known as Kneadatite Yellow/Blue Epoxy. Want to see the power of re-branded markup? Take a look around at the price difference using that name instead.

But before you buy, there's some thing worth noting here: the edges of the two colors are joined. This is for a substance that you activate by mixing. Unless you're desperate and in need of a quick putty fix, don't buy tape putty! Why? Because the epoxy will have started mixing along that contact point. The putty for about 1mm on each side of the join will still be trash, even straight from the manufacturer. Older putty will be even worse. You can tell it has been on the shelf too long as the yellow side will develop a definite green tint compared to fresh epoxy. But rather than hunt for the freshest of fresh, there's an easier solution: buy seperately packaged block or tube putty. These will come in a larger quantity, but the price will usually reflect buying bulk. For this you'll get a much better initial quality and raw putty lifespan. My current supplier of choice is Gale Force 9.

As an alternative to Green Stuff, it is worth noting Procreate's Grey Stuff. It is also available from Gale Force 9 in separate tubes. The difference between the two? Grey Stuff's pretty new on the market so there aren't as many tutorials using it. It's a little less sticky and forms sharp edges quite nicely. It's also softer, easier to make mistakes with, and harder to learn how to form. Green Stuff rounds easier and better lends itself to organic or soft forms. The higher contrast of color also makes it easier to see against plastic or metal figs. If you're just starting out, then I'd steer you towards Green Stuff. If you've already done some Green Stuff and are looking to do something more advanced, try Grey Stuff.

Now that you have your epoxy of choice, let's talk "care & feeding". As unmixed epoxy ages, it will start to swell. You can see this in the older tape epoxies on the shelf... anywhere the tape is bent you can observe a slight puffiness to the creases. If it's really old (1 year+), you might even see where it has puffed out past the plastic sheathing at the cut ends. You might say, "So what? I'll be smoothing it out when I sculpt." The thing is, epoxy that's swelling in the wrapper will also swell when applied to the fig. This might not be an issue if you're sculpting something lewd and Slaaneshi, but your Space Marine Commander's face will look like he's allergic to bees. The biggest causes of this aging are heat, dryness and oxidation. So just keep your putty cold, moist and out of the air! Cut your block up into smaller chunks, put these in a plastic baggie and FREEZE THEM! Your putty can keep "like new" freshness for several years like this.

Now typically you'll want a 50/50 mix of putty. More blue will make the final epoxy harder but the sculpt will also cure faster. More yellow will allow a longer working time or softer/smoother pieces, but will also take longer to cure. If you really want to get fancy, you can also mix in some Brown Stuff or other epoxy. Green Stuff and Grey Stuff can be a bit bendy and tear it torqued. The extra rigidity of mixing in Brown Stuff also makes it easier to sculpt and retain sharp edges or points.

Now you've got your putty and idea for something to sculpt... let's mix some putty. First, cut off two pieces of putty of the approximate total volume you think you will need. Invariably, this will always be about half again to twice what you actually need. Excess can be used to fill in bases or create decorations.
Roll the two pieces out into thin tubes and then twist or braid them together.
Put a bit of your lubricant of choice on your forefinger and thumb, as from here on out the putty will be very sticky until dried. Smash your little braid flat, twisting and mixing like taffy. It shouldn't take very long before you can squish it flat and observe a smooth and even color. At this point I'll usually roll it into a small ball to reduce surface area and slow the curing process. (Note that the 3rd picture is just the initial squish. The putty is NOT well mixed at this point and should be worked more until you have an even color.)

For some additional links on putty epoxy, I'd suggest the following resources:
Warpshadow's Putty & Clay page. (Horrid colors/design, but great info.)
James Van Schaik's excellent putty reviews: Brown Stuff, Green Stuff, Grey Stuff. (I almost don't want to link him as he does this stuff professionally...) :-p

Cheers and hope you have enjoyed this installment. Next week: "Sculpting 103: Simple Fills, Forms & Repairs".


  1. Very helpful. There's tutorials that talk about it but I think you've gone into better detail.

  2. Nice. I never thought to roll it out like that to mix it. Thanks.

  3. Ack, I had a nice reply all done up, and my browser updated and restarted before I sent it O.o

    So, synopsis, nice add on for your sculpting tutorial :)

    I have to disagree with some of your points on grey stuff. Its only harder to work with- if you're already used to green stuff ;) From a pure sculpting standpoint it works much more like clay does than Greenstuff. My experience with greenstuff is fairly limited, as I never liked the spring back/rubbery feel and generally got frustrated with that. I've had my grey stuff about a month, and Ive used more of it already than all my previous greenstuff usage over several years of gaming. Its nice having one material that can hold edges and be filed, or mixed softer to do cloth & flesh.

    I'll admit you can get the same results with green and grey, but I think the learning curve with the grey isnt quite so steep- if you dont have to 'un-learn' the green stuff habits ;)

    On the plus side, every one of your methods works with either type ^_^