What do you do with empty Warhammer sprues? Do you trash the plastic, or do you recycle the old sprues? After building your model kits, you can recycle old plastic sprues with a bit of creativity and innovation.
In this article, I share with you 9 recycling ideas for empty plastic sprues from Warhammer and other model kits. If the pile of plastic waste bothers you, this list may give you useful ideas for a more sustainable hobby.
What’s the Deal with Recycling Plastic Sprues?
It doesn’t matter what country you’re in, plastic waste is mostly handled the same. Most of the empty sprues you throw away will end up in a landfill or incinerated. In both instances, the plastic contributes to land and atmospheric pollution.
It is quite unfortunate that plastic model kits come with a huge amount of sprue. Plastic sprues are a necessary by-product of injection molding. In injection molding, molten plastic is forced through a mold. The sprues are the “channels” that the liquefied plastic travels through to create the actual model parts. This injection molding process allows manufacturers to mass produce model kits quickly, reliably, and inexpensively.
Why couldn’t you just melt down the leftover sprues to make new model kits? Well, in theory you could, but I expect the original manufacturer likely doesn’t want or have the capacity to recycle any of their plastics either. Maybe there’s a polystyrene recycling facility in your locale?
Whatever the case may be, at some point your sprue collection will need culling. Instead of throwing plastic sprue in the trash , this article may inspire you with new ways you can recycle your plastic model sprues.
9 Ways to Recycle Plastic Sprues from Warhammer and Other Model Kits
- Make a custom putty
- Flock and decorate miniature bases
- Convert miniatures
- Repair household objects
- Kitbash or scratch build a new model
- Create terrain, model buildings, and urban scenery
- Recast into plastic card
- Melt into string or rope
- Invent a new product
Continue reading below for details about how you can recycle your plastic sprues.
1. Make a Custom Putty
Polystyrene plastic, the polymer in modeling kits, is an inexpensive and malleable plastic with a relatively low glass transition temperature. Importantly, polystyrene dissolves readily in volatile solvents, such toluene aka methyl benzene, which are the active ingredients in plastic cements and modeling glues, e.g., Tamiya thin cement.
You can use solvents to your advantage with your old plastic sprues to make a custom putty or “sprue goo”. To make the custom plastic putty, cut up your empty plastic Warhammer sprues into very small pieces. I recommend making the plastic bits as small as possible to help dissolve them in the modeling cement. Put the plastic sprue bits into a glass jar. Then, add the plastic cement drop by drop until the plastic is completely dissolved.
You will have to adjust the ratio mixture to thin or thicken the putty the way you like it. Adding more cement will make your putty “thinner”, but you’ll lose some of the plastic binder for doing cool things. But, a thinner sprue goo will be easier to work with. You’ll want to do this in a well-ventilated room, as modeling cement gives off strong harmful fumes.
Quick tip: A very thin modeling glue, i.e., a low viscosity cement, works best for making custom sprue putty, because as the modeling glue dissolves the plastic sprue bits, the putty will become sticky and thick. Thin modeling cement will help keep the putty workable. I prefer a mixture that creates a sprue putty with a viscosity like maple syrup for pancakes.
What do you use this custom putty for?
Sprue goo one of the best gap fillers you can use on plastic models. Custom sprue putty goo is a good alternative for more expensive gap fillers, such as liquid green stuff. Just be you’re careful with how you apply it. Remember, that the model cement is a polystyrene-plastic solvent, so your sprue goo can still melt your actual miniature or scale model kit surfaces. To apply the sprue goo, use a brush, toothpick, or sculpting tool, and add a bit of putty to the gap or seam you’re trying to fill.
As the solvent, e.g., modeling cement, evaporates from your sprue putty, the melted plastic will remain behind. If you’ve done your job well, the plastic fusion between your model’s parts will be neigh perfect. You can sand, scrape, and work with the dried sprue goo the same way you would as any other plastic part.
With your imagination or a Google search, you’ll find a lot of other great uses for this custom sprue putty, including sculpting and texturing special effects.
2. Flock and Decorate Miniature Bases
Making terrain and customizing your miniature bases is a popular use for empty sprues. There are many ways to reuse the plastic sprues. You can cut the longer pieces into strips to make ruined, building girders, bricks, or stonework.
To assemble these bits, use plastic cement or super glue. I prefer a thicker, more viscous glue for working with terrain and bases. This gives me more control over where the glue goes and it doesn’t run away on me.
A unique way to use sprues for customizing terrain or model bases is to use a coffee grinder to chew up the empty plastic sprues. For this, I’d recommend using a cheap grinder and not one of the expensive ones you actually need for your java habit. Here is a coffee grinder scale railroad modeler’s use for making miniature flocking material from found items. It comes with a brush and a simple push button operation. Ensure you don’t stuff the grinder with too many sprues. Don’t overwork the motor.
When you’re finished grinding the plastic, you can use the small bits to build up terrain to look like sand or mortar. Or, you can use the finer plastic in a solvent mixture to make a putty or sprue goo (shown above). Use the putty or ground up plastic sprue to sculpt and texturize building sidings, facades, or ground lay on bases or around other structures.
3. Convert Miniatures
You can use the pieces from discarded componentry or other found materials for a custom project. Naturally, model conversion (e.g., model customization) are great ways to use old sprues in new ways.
Miniature conversion is similar to making DIY terrain, but now you’re using your imagination with a smaller scale model in mind. You can use empty plastic sprues to help you convert miniatures you already own. If you’re a Warhammer 40k player, then you are familiar with Ork vehicles. On the battlefield, you’ll see Orc players field all sorts of fantastical vehicles and machinations of a warped imagination.
Use sprues to build up armor plates on vehicles, flyers, and other war machines. You can sculpt sprues with a hobby knife to sharpen the tips and add spikes to things, e.g., Mad Max style. A quick way to sharpen a lot of long sprue pieces is to use an inexpensive pencil sharpener. I do recommend using a manual sharpener, as a motorized one may not have the power or durability to handle sharpening all those plastic bits.
Because sprue plastic is relatively soft and malleable, you can shape them with a bit of heat and curve them into shapes. Build up layers of sprues to form entirely new miniatures, or augment ones you have with new subassemblies and parts. Create forms and structures to make your vision come to life.
4. Repair Household Objects
Ever break something that needed a crack filled? Bridge and fix cracks or holes in empty plastic sprues. To fix cracks or gaps, you often have to replace the original lost material. This requires using a “substitute” filler material. Empty plastic sprues are useful in this case, since you can combine the plastic sprue pieces with a two-part epoxy resin or another robust adhesive binder to form a filler material.
There are two ways you can use empty sprues to repair household objects. First, you can mix up a sprue goo or custom putty, as mentioned above, to seal cracks or gaps. Second, you can cut the sprues to size to fit the gap or broken crack in the object. Then use a super glue to hold the sprue pieces in place while you apply a slower drying epoxy to completely fill-in and seal up the gap.
I’ve used old sprues for fixing cracked plastic shells on appliances, outdoor furniture, and my kids’ toys. There are a ton of uses for sprues when it comes use them as material for repairing things around your home. Because model kit sprues are soft, it is easy to cut, shape, and sculpt them to fit whatever part needs repair.
5. Kitbash or Scratch Build a New Model
Kitbashing or model bashing is a practice whereby you can create a new model or miniature from the parts of other kits. Sometimes you simply need a new model or miniature that doesn’t exist. Or, you’ve got a powerful imagination and want to manifest a new sculpt that you’ve carried in your head for a long time. The empty plastic sprues from old kits are a great medium for sculpting things from scratch.
Scratch building or kitbashing with found objects isn’t a new concept. Using empty sprues is an obvious way to recycle the discarded bits from your other model assemblies. Of course, there are many ways you can craft a new model from empty sprues. For example, if you’re planning to make a scale model building, you could cut the sprues down into miniature “bricks” and reconstruct them piece-by-piece into a new structure.
You could also layer sprues together with hot glue to sculpt the skeleton or base form of another miniature. Because the sprues are malleable, there is quite a bit of room for you to project your vision onto the plastic material. You can make mechanized type forms, or use the plastic sprues in an organic sculpt, e.g., a golem or other fantastic creature. With caution, use heat or solvents to shape and sculpt the plastic into almost any form you want!
6. Create Terrain, Model Buildings, and Urban Scenery
Whether you’re model train enthusiast, constructing your railroad empire, or an avid wargamer reenacting an urban skirmish in a far-away land, you’ll need terrain. Use those empty plastic sprues you’ve accumulated from all the models you’ve assembled for constructing those buildings and miniature scenes. Check out this article for a reference chart to help you convert model train scales, e.g., O, HO, N-scale, to the popular 28-35mm wargaming scale.
I like using my old sprues like Legos. Cut them up and form them back together with glue into whatever building or terrain feature I need. Here’s a trick: You can hold a long piece of plastic sprue over candle or cigarette lighter and melt the tip. Using tweezers or forceps, you can pull the melted end out into a long string.
Once the plastic cools down, you can cut the plastic string into whatever length you need. You can use this melted “string” as miniature wiring for electrical power lines, stringing bows on your elven archers, or as detailing rivets on plate armor or buildings. In the latter case, you may want the diameter of the melted string to be thick or thin depending on your scale.
Another great use for sprues is to use them as the underlying scaffold for other materials you may want to use for constructing buildings. Use the sprues as the girders and cross beams to hold up cardboard or plastic card walls. Hot glue, plastic cement, or super glue work great for this purpose, drying fast and strong enough to hold up fairly large structures.
7. Recast into Plastic Card
Plastic card or plasticard is a plastic sheet that ranges in thickness, usually between 0.5mm and 2mm. For scale modelers, plasticard is purchased for a large number of uses. You can use plasticard to scratch build buildings, vehicles, small objects, e.g., furniture, interior and exterior structural details, and a host of other things.
Did you know it is possible to melt and recast the plastic sprues into plasticard? It won’t be as perfect manufactured as the plasticard you can buy , but it’ll be a great way to recycle your discarded old sprues. More importantly, recasting your sprues into plasticard is a low-cost, easy to make product you can use that is also sustainable.
You’ll need a waffle press with flat girdle plates (not the textured kind) and baking parchment paper. You may already have this around your home. Because the polystyrene plastic in model kit sprues has a fairly low melting temperature, you won’t need to use an expensive waffle press or even apply the heat very long.
Here’s what you do to make plasticard from your old sprues.
Place a sheet of parchment paper on the girdle press. Put a good number of cut-up pieces of sprues on the parchment in a shallow pile, and then cover this with another sheet of parchment. In fact, pretend you’re making a waffle.
With the heat of the waffle press on the lowest setting, close and press the cover and apply some pressure until you feel the plastic sprues give way. When you think you’ve melted the plastic flat, open the cover and carefully peel away the top parchment paper to reveal the flattened sprue plastic.
If you’ve done it correctly, you should also be able to peel away the new plastic card you’ve made from the bottom parchment paper. Be careful as the plastic will retain a lot of the heat. Experiment with the heat settings and timing to form plastic card to the sheet thickness you want. It won’t be pretty, but you can crop and shape the flattened plastic to your needs. You can use this recast plastic card in many ways, e.g., scratch building, DIY terrain, heat sculpt new forms and much more!
8. Make String or Rope
Plastic sprues melt easily. This makes it great for pulling the plastic into long ropes or strings. Although I mention this use above, it is worth mentioning again as a specific use case. Miniature string or rope isn’t something you can easily buy. The kind, thickness, and type of rope or string you need will depend on the scale and environment of your model.
Creating your own string or rope for scale miniatures or models is an old concept, but still relevant. The best way to melt polystyrene plastic is over a low-heat flame, such as a candle, a lighter, or alcohol lamp.
To create your plastic string or rope, simply hold your length of plastic sprue over the open flame, moving it constantly back and forth to avoid concentrating the heat on any single point. As the plastic starts to melt, pull the sprue gently apart to stretch the softened plastic. You can find more details here about how to pull rope and string with melted sprues.
The more evenly you distribute the heat, the easier it will be to keep the string the same diameter throughout the melting-pulling process. You’ll need to experiment a bit with this, as the way the plastic behaves will depend on the thickness of the sprue, the temperature applied, and how thick you want to make your string or rope. Finally, remember to clip off any nubs or “branches” from the sprue. For an even melt, you want a single length of “clean” plastic sprue with a consistent thickness along its length.
Once you’ve removed the plastic from the heat source, it will cool down quickly. The thinned-out string may be fragile, so I suggest laying the whole piece on a flat surface immediately during cooling to avoid break it. Use a hobby knife or clippers to chop off the excess plastic you don’t need. Based on my experience playing around with this technique, you should be able to reliably pull a 3-4 cm length of string with equal thickness from a 8-10 cm length of empty plastic model sprue.
9. Invent a New Product
Everything you do with your old sprues requires your imagination and bit of ingenuity. I did a deep dive on Google to find other ideas people have come up with to recycle their plastic model sprues. You’d be amazed with some of the things I’ve discovered. And, rather than list them all. I’ve grouped them here.
Here are a few unique things I’ve found that people have made with their accumulated piles of plastic sprues:
- Pencil holder
- A key/coin tray
- Dice tower
- A shell for RC car
- Abstract sculpture
- Plant pottery
- Paint organizer stands
- And, much more!
With polystyrene plastic, you can make all sorts of things that go beyond tabletop miniatures and scale models. You can invent and craft up totally new objects.
Sprue Terrain Ideas for Wargaming and RPG Tabletop Games
I want to mention that as a tabletop wargamer, sprues are quite abundant in the hobby. They always accumulate as we collect and build model kits. Of course, the possible compulsive hoarder inside us makes it difficult to throw away anything. This is a suffering thought: Maybe, one day I’ll need that!
If you play Warhammer 40k, Age of Sigmar, or use miniatures and terrain in your RPG games, e.g., Dungeons and Dragons, DnD, or Pathfinder, then making terrain features is certainly a good way to reuse your plastic refuse pile.
Check out my Pinterest board for more sprue recycling ideas for all sorts of wargaming and RPGs needs.
Easiest Way to Paint your Plastic Sprue Creations?
Let’s keep it simple.
Say you’ve created a new terrain piece from old sprues. What is the best way to paint it? Well, given that you’ve probably painted other miniatures assembled with the same plastic, you could use the same method. For simplicity, however, the fastest and easiest way to paint most structures, including sprue creations, is to start with a good plastic primer.
Vallejo Surface Primer is my recommended primer for almost any model. For best results, the ideal way to apply a primer is with a spray application, e.g., airbrush or aerosol. If you don’t have an airbrush or rattle can primer available to you, then a brush-on application will work fine. Just make sure you coat your sprues with an even coat of primer without bubbles.
Once your primer is dry, you will have a nice working surface for acrylic model paint. Any hobby brand will do. After you get all your colors painted, a good wash or dip in quickshade will help you pull up contrast and improve definition of finer details. When you’re done painting, make sure you protect your paint job with a durable sealant or varnish.
I hope you enjoyed this article. Our hobbies are a privilege. They provide hours of enjoyment, a host of learning opportunities, and an unmatched sense of discovery at every turn. Although waste is natural in any human endeavor (it is a part of living in a material world), we can mitigate the harm it does through the choices we make, e.g., shut off room lights and appliances when not in use.
As wargamers and modelers, we have proven that we are individuals with powerful imaginations. In regards to the piles of empty plastic sprues that we accumulate from modeling and assembling miniatures, we have many ways to recycle them back into the hobby space. Instead of immediately throwing away sprues, we can store and use them to enhance terrain and models, or make props for our tabletop games.
Of course, I’m sure I missed a few points here and there. Are there other niche ways to recycle the plastic from model kits? Do you have any examples of how you reused parts from old plastic model kits?
Until next time, happy modeling!