Hot Wire Foam Factory

216 East Laurel Ave, Lompoc, California, 93436, United States     1-866-735-9255     1-805-735-9255     1-805-735-9285

Styroplast #024


Weight 3.50 lbs
SKU 024-QT
Fortifier/additive: Not an additive
Feel: Smooth Plastic
Application time: 10-20 Minutes
Work time: 30-45 minutes
Cure time: 12 hours
Weatherproof: Weather Resistant
Sandable: Sandable only before completely set
Paint/Stain: Second coat or paint MUST be applied within 2-12 hours or will not stick
Compatible with: Can be applied over any other coating; Grit can be used on top as texture
Our Price: $29.95


Whether you are producing signage or protecting delicate forms for themed scenery, Styroplast will outperform all other coatings. Our one-of-a-kind brush-on encapsulant has a fast set time and clings well to vertical surfaces. It is designed to provide an impact and fire resistant shell for numerous substrates including EPS/Styrofoam, insulative foams, and wood. Our formula is extra thick, as it especially formulated to be the best brush on foam encapsulent. Spray application is not recommended. Very little weight is added to the foam structure reducing the need for structural support. Water resistant and chemically inert once cured, it is human- and animal-safe. Superior hardness, fast cycle time, easy to apply, lightweight and short cure time. Environmentally safe once cured. Superior hardness and greater moisture resistance than epoxies.

Coverage: This coating is very strong, even when applied very thin:

1/64 inch thick
1/32 inch thick
1/16 inch thick
1/8 inch thick
1/4 inch thick
Quart Coverage:
26 sq ft
13 sq ft
6 sq ft
3 sq ft
1.5 sq ft
Gallon Coverage:
103 sq ft
51 sq ft
26 sq ft
13 sq ft
6.5 sq ft


Simple Brush-On Application Tips: Mix With Part B Warm. Mix EXACT proportions. (See Mixing, below.) Apply in Cool Dry Area. Dry in Warm Humid Area.
Apply multiple coats when needed. Best to apply 2-12 hours after each coat is applied.  Easily sanded between coats. Use our Medium Mesh for extra strength, especially in seams and corners. 

Material PreparationApplication in humid conditions may create gas bubbles that rise to the surface during drying. Thoroughly power mix Poly component before beginning to apply. In large quantities, usually this takes a minimum of 5 minutes per 1 gallon pail with proper mixing equipment. Mix with a slow speed drill and paddle mixer. Hand mixing is fine for small quantities.We highly recommend using our accessory Syringe for small batches (see the Related Products link at the bottom of the page). An air conditioned room will deliver an ideal low humidity and slow drying environment. Move coated object to a warm area to promote faster drying. Warming Part B to 70-75 degrees before use will make mixing much easier.

EquipmentOrdinary paintbrush, notched trowel (preferred), or squeegee. Clean up (before mixture dries) with acetone or MEK.

ReactivityPotlife (brush): 15 minutes @ 76°F (Up to 30 minutes in cool dry environment); Potlife (trowel):12 minutes @ 76°F (Up to 20 minutes in cool dry environment.)

Cure TimeApplied coating will set in about 2 to 5 hours at 70°F, depending on film thickness, liquid material temperature and the substrate temperature. Generally complete cure takes from four to five days at room temperature. Product can be placed into service after one complete day of cure at 70°F minimum. After four days cure the hardness is around 65 shore D . Higher hardness may be attained by post heating the part to 90 – 110 F after 6 hours cure time. Prime or paint the plastic coated part the next day, or better, later the same day. If you paint after 12 hours you will need to lightly sand the surface, or better to apply an epoxy primer for paint to stick.

Mixing: 1 unit ISO: 3 units POLY by volume or 1 unit ISO: 3.55 units POLY by weight. Must be very exact proportions. Highly recommend using our reusable accessory measuring Syringe or an accurate scale for small quantities. Neutral (tan). Paint within 12 hours or use epoxy primer for best bond. Or just lightly sand after 12 hours for good adhesion.

Fire Resistance: Styropalst is self-certified as UL-94 V0 at 60 mils thickness. Flash PointASTM D-56 (TCC): Greater than 200°F

Chemical Resistance: Hydrolytic Stability: Recovers after 10 days 150°F immersion. Generally resistant to most dilute aqueous agents when cleaned off within 10 hours of contact. Very difficult to stain by virtue of its high hardness and low porosity. Constant or frequent immersion service not recommended.

Tensile Properties: ASTM D-412; Tensile Strength: 2742 psi; Elongation: 9.7 %; Yield Strength: 2653 psi; Elastic Modulus: 17,127 psi.

Tear Resistance: ASTM D-624: 156 lb/in.

Hardness: ASTM D-2240; Shore D: 65 - 70 depending upon post cure Conditions.

Liquid Component Properties: Solids: % Nonvolatile (wt): 100% Viscosity: Poly Component: Moderate - High @ 77°F; ISO Component: 200 cps @ 77°

Density: Poly Component: 12.11 lbs/gal. ISO Component: 10.3 lbs/gal

Toxicity: ISO Component contains isocyanate (the ISO side has similar health hazards as Gorilla glue). Due to toxicity, spraying is not recommended. When brushing, ventilation, gloves and protective clothing required during application.

Shelf Life: The shelf is twelve months for Part B and six months for Part A. They will last longer than that when stored properly. The ISO, when left open, will draw moisture out of the humid air and create bubbles, so keep container closed at all times.

WARRANTY: HWFF Inc./dba Hot Wire Foam Factory warrants this product to be of merchantable quality when used or applied in accordance with the instructions herein. The product is not warranted as suitable for any purpose or use other than the general purpose for which it is intended. Liability under this warranty is limited to the replacement of its product (as purchased) found to be defective, or at the shipping companies’ option, to refund the purchase price. In the event of a claim under this warranty, notice must be given to The Hot Wire Foam Factory in writing. This limited warranty is issued and accepted in lieu of all other express warranties and expressly excludes liability for consequential damages. MSDS available.