Ruby's Picks: Flexible Slip

Every week, our trusted shop dog, Ruby, shares one of her favorite products! This week, she's focused on Flexible Slip!

Flexible slip, also known as mannequin rubber, consists of a mixture of latex rubber and clay and is slip cast into plaster molds to create hollow, light weight , tough parts. This material air dries to the consistency of hard leather. Once dried, flexible slip can be painted with acrylic paints and is fantastic for making items like doll and puppet heads, Christmas ornaments and display props.

Some common uses for flexible slip include:

Casting: Flexible slip is poured into dry plaster molds to create semi-flexible castings that can capture intricate details.
Artistic Applications: Artists often use flexible slip to create sculptures and artworks.
Restoration: It can be used in restoration projects to replicate missing or damaged parts of historical artifacts or architectural elements. Especially useful for simulating lincrusta.
Additionally, because flexible slip is made of materials like latex and clay, it is virtually non-toxic!

Using Flexible Slip: Using flexible slip effectively involves several key techniques to ensure a successful casting.

Here’s a step-by-step guide:

1. Prepare Your Workspace: Ensure your work area is clean and well-ventilated.
Gather all necessary tools and materials: flexible slip, mixing containers, stirring tools, molds, release agents (if needed), and safety equipment (gloves, eye protection).

2. Prepare Your Mold: Ensure your mold is clean, dry and free of any dust or debris. If this is the first outing for this mold it may be desirable to apply a suitable release agent to the mold to aid in the demolding process. Powdered mica is commonly used.

3. Mixing the Flexible Slip: Stir the Flexible Slip thoroughly until it is smooth and free of lumps.

4. Pouring the Slip: 

• Slowly pour the mixed flexible slip into the mold until it is full.
• Tilt the mold as needed to ensure the slip reaches all areas and corners without trapping air bubbles.
• Tap the mold gently on a flat surface to release any trapped air bubbles and help the slip settle evenly.
• Allow the flexible slip to sit in the mold for 20-40 minutes to create a good film of material for your casting.
• Pour excess material out of your mold (can be poured right back into your Flexible Slip container for re-use) and allow remaining material to cure for 12-24 hours.

5. Curing and De-molding: Once cured, carefully de-mold the casting. Take care not to damage any delicate details as it will be soft when first de-molded.

6. Finishing: Trim any excess material and clean up any seams or imperfections on the cast piece as needed. Once the Flexible Slip cast has fully hardened it may be sanded to further refine the surface prior to painting. Acrylic paints are your best option for painting Flexible Slip.

And there you have it! Flexible Slip is a great low-tech material. Sometimes it's the simpler things in life...like a good game of fetch!