News and random musings from the Sculptdude.

Thursday, August 19, 2010

Sculpting Tools and Putty

SCULPTING MATERIALS


POLYMER CLAYS


Polymer clay is not a sculpting putty, per se, but is a clay-like plastic polymer that hardens when heat is applied. There are many different brands and formulations of polymer clay, each with their own specific properties. These include Beesputty, Cernit, Fimo, Kato Clay, and Sculpey.



Beesputty Plastic Summer Firm
Beesputty.com
Beesputty on YouTube

My primary sculpting material these days is Beesputty. It is a super awesome polyclay formulated specifically for sculpting miniature figures which has a wax-like feel that allows it to stick to itself and directly to armature wire.

Fimo and Sculpey are very "dry" clays and will not stick readily to wire armatures unless you coat them with a layer of epoxy (like greenstuff) first. With Beesputty you can sculpt directly on the wire which cuts out a step and makes sculpting more efficient. I can block out an armature and then bake that understructure, then after it cools, add more Beesputty over the top to sculpt the anatomy or details.

Unlike epoxy which cures by a chemical reaction when the two parts are mixed, polyclays harden when you bake them in the oven. The benefit with polyclay is the unlimited working time until it is baked. With epoxy putty, I'm always competing against the clock. Also, polyclays have zero "memory", or elasticity and stay put when you form them.

Baking Polyclays

The Beesputty package says to bake at less than 130ºC (266ºF) but I usually bake at 135ºC (275ºF) for 30-40 minutes. You want to make sure that your sculpt or armature/support wire does not come into contact with the oven rack or baking tray. It can cause the sculpt to heat up too much and crack. My oven is small and has a timer. I allow the oven to shut off and cool down before removing the baked pieces, also to prevent cracks.

I use a dedicated electric counter-top toaster oven to do all of my polyclay baking. Any sort of oven-proof dish or tray is fine but I highly recommend putting a ceramic tile on the baking rack to set your corks on. Once the sculpt is in the oven, the polymer clay will get softer in the heat before it cures hard. So you need to keep in mind if your sculpt is sitting right on a tray, the sculpt will develop flat spots wherever the contact is and may crack when cooling.

The baking temperature and time is usually low enough not to scorch any corks or wood blocks you may be using to sculpt your figures on. However - be cautions of using synthetic wine corks as they may not be resilient enough to the heat and may cause problems.

EPOXY


Epoxy putty is a two-part substance that hardens by chemical reaction once the two parts are combined. Commonly, miniature gaming figures are sculpted from a plumbing putty that will withstand the heat and pressure required for the mold making process. This putty comes in a blue part and yellow part that combines to a bright green color. Original sculptures, regardless of the color of the putty used to create them, are still commonly referred to in the industry as "greens".


What kept me from sculpting miniatures for many years was the inability to control the material of the actual "green stuff". I had compared it to sculpting with bubblegum. When I first tried my hand at it in the mid 90s there was no internet resource or community accessible for an isolated noob. After jumping back into the hobby again in late 2005, I discovered there was a wealth of info online and promptly completed my first few sculpts. I still didn't like green stuff very much because it was so different from the plastilene and polymer clays I was already so familiar with.

The very first thing I ever sculpted with Green Stuff - circa 1996

So, taking lots of tips from pros and others in the hobby I began to experiment with different putty mixing trying to get a better workability to what I was used to. The most frequently asked question I get is about the difference between green stuff and brown stuff. I have summarized it to this:

Green Stuff is a two part epoxy putty that has an elastic property making it suitable for organic sculpting. It stays quite flexible after curing. This also makes carving, drilling, sanding or scraping extremely difficult. Green stuff is a pipe sealant manufactured by Polymeric Systems as Kneadatite®. It was later repackaged and marketed to sculptors after it became widely used for sculpting miniatures.

Brown Stuff is an epoxy putty the has a more traditional clay-like feel to it making it suitable for non-organic sculpting, like weapons and armor. This makes it very suitable for carving, drilling, sanding or scraping. This also makes it brittle and very susceptible to breaking. Brown stuff is also a pipe sealant manufactured by Polymeric Systems but, as of this writing, has been discontinued.

Initially, I mixed the brown and green putties to get the best properties of both and greatly reduced the frustration of their downsides.



ProCreate was marketed in 2006 and I found a superior all-in-one putty that works for everything. Depending on the mix of white to black the cure and hardness will be affected. I personally prefer mixing it at a 1:1 ratio. It can be carved, drilled, sanded or scraped with good results. In all respects ProCreate works and behaves pretty much like the green/brown putties. The biggest advantages to me are the lack of "memory" (elasticity which makes fine details extremely difficult to get sharp), low tack (works well with an assortment of tools) and the overall neutral color (no green screaming into my eyes). There are a couple of things to watch for, though. When mixing it, there is a noticeable residue left on your fingers. This will create a "slip" if water is used as a lubricant during mixing. Be sure to wash your hands after your sculpting sessions.

I cannot stress how unsanitary it is to lick your sculpting tools, that is defintely NOT recommended when working with this particular putty.

ProCreate and other putty is available through these online suppliers:
Kraftmark - manufacturer's site
Bombshell Web Store

THE SECRET FORMULA

I observed Werner mixing a tiny bit, maybe 10% or 15%, of Fimo into his Green Stuff one year when he attended ReaperCon. When I asked what that did he said it it accomplished two things, one, it lengthened the working time, and two, it reduced the elasticity of the putty. I asked if the Fimo caused a problem with the curing of the putty and he said that the poly clay is in such a small amount that any heat (like form a lamp) set up the putty as normal.

I tried it for several years before moving to ProCreate. For the most part I felt I didn't need to add anything to Gray Stuff because I was very happy with how that material performed. After struggling with a couple of specific pieces several years later I had a conversation with Reaper sculptor Kevin Williams who offhandedly suggested I add a little Fimo to ProCreate.

When I did that - something magical happened! It made the material supple and easy to feather seams, plus it extended the working time for another 30 - 45 minutes. This gave me total control over the material. Plus I have also observed that cured ProCreate that has Fimo added will also cure harder and a little more rigid, than putty alone. Now most things I sculpt like anatomy, costuming and drapery are all blocked out with with putty that has Fimo added. Smaller detailed areas like faces, hands and equipment are still made with just straight putty.


OTHER EPOXY

It is also worth mentioning another couple of putties that are extremely useful which are Aves Apoxie sculpt and Magic Sculp. Both of these are formulated differently from the green or brown Kneadatite and even the ProCreate.


According to the Aves web site, Apoxie® Sculpt offers economy as well as performance. This 2-part product has a putty-like, smooth consistency, and is easy to mix & use. It is safe and waterproof with 0% shrinkage/cracking! Working time is 2-3 hrs. Cures hard in 24 hrs., and has a semi-gloss finish. Adheres to plastic, resin kits, wood, metal, ceramic, glass, polymers, foam, fiberglass, & more! Can be seamlessly feathered before set-up, or sanded, tapped, drilled, carved, lathed, or otherwise tooled after set-up, without chipping, cracking or flaking.

Magic Sculp's web site says it is the two-part epoxy putty specifically designed to meet the needs of modelers, crafters and sculptors alike. One of the only epoxies that will smooth out with water. Its grain structure is finer than any other product available and will not shrink or crack even when formed in large structures. It can be shaped by hand or with modeling tools, sanded, carved, painted; you can attack it with a grinding tool and the cured material will not break apart or lose its shape. Magic Sculp will cure at room temperature.

Both of these putties have similar properties to Milliput Superfine White, but are less expensive than importing Milliput from England.

Curing is something the putty does on its own through a chemical reaction. Since the material is not polymer clay (like Sculpey, Fimo or Cernit) it does not need to be baked at higher temperatures for it to harden. You may hear sculptors refer to a "putty oven" and "cooking" their sculpts. This is similar to an Easy Bake Oven for your putty. Higher temperatures cause the putty to cure at a faster rate. Most putties have a working time from 1 to 4 hours and up to 24 hours for a solid cure. Sculpting in stages allows greater control over details and permits working on specific areas of a sculpt at a time. Rather than waiting four hours for a weapon to cure before it can be attached to hand, you can "cook" the putty under a hot lamp and then after it cools for a few minutes, proceed with completing that portion of the sculpt.


Putty Oven

My cooker is a custom built job from a one gallon sized paint can, aluminum work light, a 60W bulb, and some bit of cork. I trimmed the lamp shade with old scissors and epoxied the light to the top of the can with Aves putty. A similar rig can be made with a large coffee can.

Molds for the sculpts during the vulcanization process can run between 300°F and 330°F. I have clocked the temp of my putty oven at just over 200°F which is plenty enough to make sure it is thoroughly cured before going to mold. I like to leave my sculpts in there from 20 to 45 minutes depending on thickness.

The opposite is also true, the cure time of putty can be slowed by placing it in the freezer. If you have mixed putty you'd like to use at a later time (like after lunch or an episode of Game of Thrones) you can place it in the freezer to slow the curing rate. I don't have any data on how long it actually extends the working time but I've left it for a couple of hours and it was still workable. I also store my packages of extra putty in the freezer until I get ready to use it.

____________________________________________________________________________

SCULPTING TOOLS 

These are some of the contents of the Bombshell Sculpting Kit that I use for all my sculpting.



Here is how I have now pared down my essential tool collection. The tools I use the most are the absolutely necessary #62NW5 Double Ended Dental Pick which is similar to the Wax #5 tool. It is my "go-to" tool for about 80% of all my sculpting tasks. You can grind a sharper edge on it and then keep it smooth with nail polishing pads. My other favorite tools are the Spoon Shaped Putty Knife, a flat chisel and round tapered clay shaper, a disposable #11 scalpel which has been dulled a bit with sandpaper or a file, and a "pokey" tool which has a tapered needles point on the end.


Other useful items are a container for water. You can use a spent plastic blister pack with a bit of foam in it to make a sponge. This is handy to keep your tools wet without saturating them. I stick some blobs of putty onto a plastic divider from those plastic case divider inserts. This makes it easier to cut off bits of putty to mix without having to dig it out of the packages each time. You can also use a plastic swatch cut from a clean plastic milk jug instead of the dividers. I cover this with a bit of plastic wrap when not being used to keep it free of particles. A quick rip peels the plastic right off.



I also have a little spritz bottle of rubbing alcohol handy to keep my tools clean. Uncured putty cleans right up with a bit of rubbing alcohol. Alcohol can also clean metal to remove the talc powder that is used in molds and the putty will stick better. Purell handy wipes work wonders at getting your hands and tools clean too.

Vaseline petroleum jelly is very handy for lubricating tools and various smoothing techniques. If you experience trouble getting fresh putty to stick on areas that are cured after using Vaseline to smooth them, clean the area with a bit of rubbing alcohol first before applying the fresh putty.


THE PROCESS

Although in these examples I am using Pro-Create putty, it was a process I developed using regular green and brown stuff. So it is suitable for those putties as well.



Normally I will wet my cutting tool and slice off a chunk of the white part. Then I clean the blade so as not to contaminate the black part, wet the tool again and then cut a chunk of that the same size of the first. Cutting the putty this way allows me to get an exact amount to mix and produces less waste.

I knead the two parts folding them over and over until the color is uniform. I tend to over-mix my putty a bit after the color is smooth. This firms it up a little and assures both parts are blended.


Swatches of plastic are very handy for creating all manner of items. Here I use the divider from a plastic case divider insert again. I find these little dividers very durable and will not curl up under the heat of a putty oven like milk carton plastic tends to do.

Here I begin by sticking the putty to the plastic card and begin to shape a pile of stones for a figure's base.





Once the putty has cured, I use my cutting tool to carefully pry the part, in this case a pile of stones, off the plastic divider. This technique is very useful for creating swords, shields, guns, bases and other objects. Two-sided items like guns can be made easily by sculpting one side first and then after completing all the details and curing, the item is popped off and the opposite side is detailed.

Plastic wrap is also very useful! It is extremely handy in smoothing large areas, especially with a bit of Vaseline applied. Once the area has cured, the Vaseline can be cleaned off with a little alcohol and fresh putty applied for the next stage. The best trick I learned from a classes at ReaperCon was belts and straps. A blob of putty can be stuck to plastic wrap and then cut to shape. By popping the shape off of the plastic wrap with the side of your scalpel, it can be applied to the sculpture and then smoothed into place. The best plastic to use for this technique is heavy freezer storage bags cut into 2" squares.

This rambling collection of tips hopefully has encouraged you to give sculpting a go. It wasn't intended to give any instruction in actual sculpting, that is a whole 'nother topic! But, this should give you a good starting point to using and handling various sculpting materials. If you are already doing figure conversions, you are half way there to making full figures. Give it a shot!

---Patrick