Mastering Hybrid Resin Casting: Techniques, Materials and Tips

Hybrid resin casting opens a world of creative possibilities for woodturners, artisans, and hobbyists. Combining resin with natural materials like wood scraps, pinecones and burl -- or scraps of soft metal and shredded paper -- creates unique blanks that reveal stunning patterns and colors when turned on a lathe. Layering resin with other materials -- such as wood slabs, dried flowers or seashells -- creates amazing tabletops, cutting boards and wall art. If you've ever admired a beautiful river table, with blue "water" swirling between two exotic shorelines, that's hybrid casting on a large scale.

This post explores the essential techniques, common hybrid materials, casting methods, and tips to bring out the hidden beauty inside hybrid resin blanks. Whether you are new to resin casting or looking to refine your skills, understanding these elements will help you create pieces that truly stand out.

Hybrid resin blank showing wood, burl and resin layers

Close-up of a hybrid resin blank combining wood, burl and vibrant resin, ready for turning on a lathe. This particular blank is destined to become a moonscape sphere.

Understanding Hybrid Resin Materials

Hybrid resin casting involves mixing resin with other materials to create blanks that combine the best qualities of each component. Common materials used in hybrid blanks include:

• Materials from nature: Natural materials add texture and warmth, while resin fills voids and creates colorful accents. Natural materials might include wood, bark, burl, dried ferns or flowers, loofahs, coffee beans, empty wasp nests, twigs, dried cactus spine, sea sponge, and just about anything you can find in nature.

• Metals: Soft metals like brass or copper embedded in resin provide contrast, weight and unique patterns. Empty shell casings, soft metal shavings and wads of copper wire are examples.

• Objects: Stones, seashells, crystals, figurines, plastic mesh, photos, shredded obsolete currency, colored pencils, found objects...the possibilities are endless. Objects suspended in resin add visual interest and depth. Some objects might be too hard for turning but could be used to create beautiful scenes in river tables, lamp bases or wall art.

• Pigments and Dyes: These are mixed into resin to produce vibrant colors or effects like glow-in-the-dark, swirls, or metallic finishes.

  
  

Each material brings unique challenges and benefits. Natural materials, for example, sometimes require stabilization before casting to prevent air bubbles or chipping. Other objects, such as metals, need careful placement to avoid air bubbles and ensure proper adhesion. Pigments must be compatible with the resin type to avoid curing issues.

Methods of Hybrid Resin Casting

Casting hybrid blanks involves several key steps that affect the final result:

1. Preparing the Materials

• Stabilizing Wood and Other Porous Materials: Wood with cracks or punky soft spots, and any other porous material, can usually be stabilized first by soaking in a special stabilizing resin. Cactus Juice is one example. The item is submerged in the resin, placed under vacuum for a period of time, and then baked to cure. This draws air out and fills the voids with resin, which strengthens the material and prevents chipping and shattering during turning. It also prevents air bubbles from forming during the curing process. Stabilization is a process we won't cover in depth here, but we'll talk about it in a future article. There are lots of resources available on the internet, as well.

• Cleaning and Drying: All materials must be clean and dry to avoid bubbles or poor bonding.

• Cutting and Arranging: Pieces of wood, metal or stone are cut and arranged in molds to create interesting and aesthetically pleasing patterns. Be certain not to arrange objects in such a way as to trap air underneath.

  
  

2. Mixing and Pouring Resin

• Choosing Resin Type: Epoxy resins are common, and polyester resins are sometimes used. Epoxy offers longer working time and less shrinkage, while polyester cures faster but can be more brittle. Epoxy is easier to work with and is more typically used. Be careful to choose a two-part epoxy resin that is designed for casting.

• Adding Pigments: Mix pigments or dyes thoroughly for even color distribution. Create swirls by first pouring one color and then swirling another into it, using a stick or other utensil.

• Pouring in Layers: Pour resin in layers to build depth and avoid overheating. Layering allows embedding objects at different depths.  It also allows the use of  resins that might be limited by pour depth. 

• Choosing Colors: Choose colors that compliment -- but do not hide -- the hybrid material you are using. If an embedded object is meant to be visible within the blank, be sure to consider transparency of the resin.

  
  

3. Curing and Demolding

• Curing Time: Follow manufacturer instructions for curing times. If using a pressure pot, leave the mold under pressure until fully cured; otherwise the collapsed bubbles might reform once the pressure is released.

• Demolding: Once fully cured, carefully remove the blank from the mold.

Burl &Resin Sphere, created by @ToddGunter 

Finished Turning Project: This is a moonscape sphere created from a hybrid blank similar to the one shown above.

Revealing Hidden Treasures on the Lathe

Turning a blank on the lathe reveals some of the best magic of hybrid casting. As layers are shaped away, hidden patterns, colors, and textures emerge. Here are tips to maximize the visual impact:

• Use Sharp Tools: Resin can be abrasive. The embedded material might be of a different hardness than the resin. Sharp tools reduce chipping and produce cleaner cuts.

• Sand and Polish: Progress through fine grits to bring out the resin’s clarity and shine. Sanding and polishing is a bit different with resin:

  • With wood only, you might typically sand up through a 220 grit to prevent closing the wood grain and causing resistance to polishing.

  • With resin, you're polishing plastic. To achieve the finish you want, you might work up to 600 grit or even higher.

• Apply Finishes: Use finishes compatible with resin and wood, such as CA glue or wax, to enhance depth and protect the surface.

  
  

Creating Depth by Layering Materials

Layering is a powerful technique to add dimension to hybrid resin blanks that won't be turned on a lathe. Consider these approaches:

• Alternating Materials: Pour resin over and around wood pieces, allow to cure, then add additional resin layers with different pigments or embedded objects. For added interest, allow the resin to "set" but not cure before placing another object onto the resin surface and pressing it in, slightly at an angle. (Be certain not to create a cave where an air bubble might get trapped during the next pour.)

• Embedding Objects: Place small items like metal flakes, dried flowers, or stones between resin layers. This is especially fun for adding swimming fish and water plants at different depths in a water scene.

• Using Transparent Resin: Clear or translucent resin layers allow light to pass through, creating a sense of depth.

• Varying Colors and Textures: Combine opaque and transparent resins within a piece, or mix different pigments to create contrast. Use varying shades of blue to represent water. Pour clear resin over items you want to make fully visible.

  
  

Layering requires patience and planning but results in blanks that look like miniature landscapes or abstract art.

Considerations for Different Materials

Each material in a hybrid blank behaves differently during casting and turning:

• Natural Materials: Might need stabilization if porous or cracked. Avoid excessive moisture to prevent bubbles. Use weights or clamps with non-stick clamping cauls clamping cauls to prevent lightweight materials from floating. In a landscape, hot glue could possibly be used at the bottom of the item to anchor it.

• Hard Materials: Don't use hard materials such as rocks or solid chunks of metal to create a turning blank as these will likely damage your turning tools. These can be wonderful in river tables or artistic pieces, though.

• Paper & Photographs: These should be sealed to prevent air bubbles forming around the paper edges during curing. There are quite a few resources online about sealing paper for resin casting.

• Dried Flowers and Other Plant Material: Flowers are full of air, but they can be treated with various materials to seal the cell structure. We'll address some of these sealing options in a future article. For now, a quick internet search will reveal countless solutions.

• Metal: Lightweight metals might be appropriate for turning projects or shaped pieces such as knife scales. Harder metals may work well for other applications.

• Resin: Choose resin with low shrinkage and good clarity. Follow the resin manufacturer's instructions regarding depth of pour and curing time. Some resins can only be poured to a 1/8" depth, while others allow deeper pours, typically only up to about an inch. It's critical to follow manufacturers' guidelines to avoid adverse reactions, such as crazing, cracking or failure to cure.

• Stabilization Resin vs. Casting Resin: Don't confuse the two.

  • Stabilization resins that solidify the porous material are not used to create a finished resin blank. The treated material is hardened by heat after being removed from the liquid.

  • Two-park epoxy casting resins are mixed to create a chemical reaction in order to harden. This is the resin that you use to create a blank.

• Pigments: Use pigments designed for resin to prevent curing problems or discoloration. There are many options on the market.

  
  

Testing small batches before large projects helps avoid costly mistakes.

Practical Tips for Successful Hybrid Resin Casting

• Use a pressure pot to reduce bubbles in resin. Note: the pressure crushes the bubbles to such a tiny size that they are not visible. This is why removing the casting from the pot too early can cause the bubbles to reinflate.

• If the project is too large for a pressure pot, use a heat gun or torch to eliminate bubbles as they rise to the surface during open casting. Resins with a longer open time work best for this method, allowing hidden bubbles more time to rise before the resin hardens.

• Work in a dust-free environment to keep resin surfaces clean, especially with layered pours.

• Wear protective gear like gloves and masks when handling resin.

• Experiment with different mold shapes and hybrid materials to create unique blank forms.

• When preparing your resin, keep in mind that the hybrid material will displace some of the resin needed to fill the mold.

• Choose a large mold to create a resin plate using larger or longer hybrid materials, then cut the cured plate into several smaller blanks. This often creates more interesting patterns than trying to fit a small amount of material into a single mold. For example: let's say you want a 3x3x3 blank with the unique effect created by pinecone scales, but your pinecones won't easily fit a mold that size. Try using a pepper mill mold (3x3x12). Pack several pinecones into the mold, and then cut the finished blank into four 3x3x3 blanks.

• Research and choose your resin carefully. Not all epoxy resins are meat for casting. Among those that are, different brands and types of resin are suited to different uses. Follow the manufacturer's instruction and tips carefully to avoid surprises.

If you have questions about hybrid resin casting, reach out. Visit LizardBlanks.com or send an email to Phil.Hahn@LizardBlanks.com.