2025 Winter Acrylic Painting Challenge, Lesson 3: Sealing in Your Sketch

/ Uncategorized
/ By Matt Philleo

Preserving your sketch: A step-by-step guide to starting your acrylic painting with confidence

When embarking on an acrylic painting journey, especially for a portrait or complex composition, a strong foundation is critical. That’s where sealing in your sketch comes into play. In this lesson from the 2025 Winter Acrylic Portrait Painting Challenge, we’ll cover a detailed, beginner-friendly guide on how to preserve your sketch while setting the stage for vibrant and confident painting.

The keyword? Confidence. When your sketch is securely sealed, you’ll paint with ease and precision. Let’s dive into the four-step process that ensures your hard work is protected and ready for layers of color and depth.

Why Sealing in Your Sketch Matters

Your sketch serves as the blueprint of your painting. Without proper sealing, colored pencil marks can smudge or bleed into subsequent layers, disrupting the clarity of your design. Sealing provides a protective barrier, ensuring the sketch remains intact and your painting proceeds without setbacks.

Step-by-Step Guide to Sealing in Your Sketch

Step 1: White Out the Grid

Start by addressing the grid lines. These guide initial proportions but should not remain visible in the final painting.

Why Use Titanium White Instead of Gesso?
Titanium white paint provides opacity without translucence, unlike gesso. It effectively covers grid lines while maintaining a smooth finish.
What You’ll Need:
- Titanium white paint
- Three brushes: a medium-sized flat brush, a small flat brush, and a small round brush
- Disposable mini cups or a small container for the paint

Process:

Dip your larger flat brush into titanium white paint.
Apply it over the grid lines, smoothing the brushstrokes for an even finish.
Switch to smaller brushes for tighter areas, such as the details near edges and inside lighter value zones.
Cover grid lines within illuminated areas and transitions like snow tracks or delicate highlights.

Pro Tip: Use firm pressure to cut around intricate details while avoiding overlap with the sketch.

Step 2: Spray Seal the Canvas

Once the grid lines are covered and the titanium white layer has dried completely (allow a few hours for thorough drying):

Use a clear acrylic spray sealant to lock in the sketch.
Hold the spray can about 12 inches away from the canvas for an even application.

This step prevents smudging while adding a layer of protection.

Step 3: Brush Seal the Canvas

For added durability, brush seal the canvas after the spray sealant has dried.

Use a soft, wide brush and a thin coat of matte medium or glazing medium.
Gently apply in smooth, even strokes, avoiding bubbles or uneven texture.

Allow the canvas to dry fully before proceeding to the next step.

Step 4: Begin Layer One of Painting

With the sketch sealed, it’s time to add your first layer of color. This layer will establish the foundational tones and values, setting the stage for depth and detail in subsequent layers.

Focus on broad, general areas first, keeping the colors light and translucent.
Use glazing techniques to gradually build intensity without losing the clarity of your sketch.

Tips for a Smooth Sealing Sketch

Patience Is Key: Ensure each layer dries thoroughly before moving to the next. This prevents smearing and uneven finishes.
Use Quality Materials: High-quality titanium white and sealants make a significant difference in coverage and durability.
Practice Makes Perfect: If you’re new to sealing techniques, practice on a small test canvas before working on your main piece.

Sealing in your sketch is an indispensable step in acrylic painting. By following this four-step process, you’ll create a robust foundation for your artwork, ensuring your sketch remains intact and ready to support vibrant layers of paint.

For more guidance, including reference materials, supply lists, and exclusive painting challenges, watch the video tutorial below and join the 2025 Winter Acrylic Portrait Painting Challenge at www.realisticacrylic.com. It’s free and packed with resources to elevate your painting skills.

Now it’s your turn! Get your brushes, titanium white, and sealants ready, and seal in your sketch with confidence. Don’t forget to join my Facebook community that a lot of artist support each other. Happy painting!