3mm vs 6mm Artefex Panels: Which One Should You Choose?

When artists talk about painting surfaces, the conversation usually revolves around canvas or wood. But more and more painters are discovering the advantages of Artefex art panels, especially those made with aluminum composite material (ACM). They’re durable, archival, and resistant to the environmental changes that warp canvas and wood.

One common question artists face when shopping for Artefex panels is: should I choose the 3mm or the 6mm thickness? On the surface, it might look like a small difference, but in practice it can affect how you paint, transport, frame, and display your artwork.

This article breaks down the differences between 3mm vs 6mm panels, explores their uses for oil and acrylic painting, plein air work, and large-scale studio projects, and helps you decide which thickness makes sense for your art.

What Makes Artefex Panels Different?

Artefex panels are built with an aluminum composite core. Think of them as a sandwich: two thin aluminum sheets bonded to a polyethylene (plastic) or honeycomb core. Unlike wood or canvas, aluminum doesn’t absorb moisture or expand with changes in humidity. That means these panels stay perfectly flat and stable, even in less-than-ideal conditions.

• 3mm Artefex panels use a solid polyethylene core and are about 1/8” thick.
• 6mm Artefex panels use a honeycomb aluminum core, making them about 1/4” thick while staying surprisingly light for their size.

In both cases, Artefex adheres professional-grade grounds or fabrics (oil-primed linen, acrylic-primed cotton, etc.), so you’re painting on a surface that’s ready to use and built to last.

Why Art Panels Thickness Matters

At first glance, thickness might not seem like a big deal. Both versions are archival, rigid, and long-lasting. But in practice, the difference between 3mm and 6mm comes down to weight, rigidity, cost, and handling.

• 3mm panels are slim, portable, and easy to frame. They’re stiff enough for most sizes, yet light enough to carry around or store in bulk.
• 6mm panels are heavier, more expensive, and extremely rigid. They’re ideal for large-scale paintings or situations where you want absolutely no flex in the support.

Most artists end up using 3mm panels for everyday work and 6mm panels for special projects. Let’s dive deeper into the scenarios where each one shines.

3mm Panels: Lightweight Versatility

If you’re looking for the best panel thickness for oil painting or acrylic painting at everyday sizes, 3mm panels are the sweet spot.

• Portability: At only 1/8” thick, these panels are lightweight and easy to transport. They slide into pochade boxes and panel carriers, which is why plein air painters love them.
• Archival stability: Despite being thin, 3mm ACM panels are stiffer and more warp-resistant than traditional 1/8” Masonite or canvas boards. They won’t bow or ripple with changes in humidity.
• Framing flexibility: The slim profile fits easily into most standard frames. If you’ve ever tried framing a thicker support and had trouble with the rabbet depth, you’ll appreciate how smoothly 3mm panels fit.
• Everyday painting: For small to medium works (up to about 18×24 inches), 3mm is more than rigid enough. You can apply heavy brushstrokes or thick impasto without worrying about movement.

For many artists, the 3mm Artefex panel is the go-to choice because it balances strength, weight, and cost.

6mm Panels: Rock-Solid Strength

When it comes to large paintings or demanding projects, 6mm panels are worth considering.

• Rigidity for large sizes: Once you move past 20×24 inches, the extra thickness really matters. A 6mm panel feels solid and doesn’t flex even when handled. That’s a big deal if you’re painting large with oil, since oil paint becomes brittle over time and cracks when the support moves.
• No need for bracing: Wood panels or even thin ACM boards often require a cradle or frame at larger sizes to keep them flat. A 6mm honeycomb panel eliminates that need. It’s built to stay flat on its own.
• Durability for handling and shipping: If you know a piece will be moved frequently (like for gallery shows or collectors), a sturdier panel can handle the wear and tear better.
• Presence: Although still much thinner than a gallery-wrapped canvas, the 6mm panels feel more substantial. Some artists like the extra depth, especially if they plan to display work without a frame.

Yes, the 6mm panels are heavier and pricier, but they’re also peace of mind in physical form. For big projects, they’re the safest choice.

Plein Air Painting: Lightweight vs. Rigid Panels

For artists who paint outdoors, weight is everything. Hiking with gear is hard enough without lugging around heavy panels.

• 3mm is ideal for plein air. It’s slim enough to fit in most pochade boxes, light enough to carry several at once, and still rigid enough to handle vigorous brushwork outside.
• 6mm is overkill for field work unless you’re painting unusually large outdoors. The added weight can make travel and setup a hassle.

If plein air painting is part of your process, stick with 3mm panels. They give you the best balance of portability and reliability.

Oil Painting: Which Thickness Works Best?

Oil paint benefits greatly from being applied to a rigid surface. That’s why so many artists are moving from canvas to panels.

• Small to medium oils: A 3mm Artefex panel is perfect. It stays flat, provides the firmness oils need, and is easy to frame or transport.
• Large oils: A 6mm panel is the safer choice. Once you start working at 24×30 or bigger, the rigidity of 6mm ensures the surface won’t flex under heavy layers. It’s also less risky for long-term durability, since oil paint can crack if the panel moves.

If you mainly work small, 3mm is best. If you dream of murals on panels, 6mm is your friend.

Acrylic Painting: Flexible Medium, Rigid Support

Acrylic paint is more forgiving than oil because it stays flexible after drying. But that doesn’t mean support rigidity doesn’t matter.

• Everyday acrylics: 3mm panels are usually perfect. They stay flat under watery washes, won’t warp, and are easy to carry.
• Large acrylic works: Consider 6mm if you’re adding heavy texture, collage, or working on very large pieces. The extra strength helps keep the surface stable.

For most acrylic painters, 3mm is plenty. But if you’re experimenting with mixed media or oversized work, the 6mm offers security.

Framing and Display

Thickness also affects how your work will be displayed.

• 3mm panels fit easily into standard frames. You can treat them like canvas boards, slipping them into ready-made frames with no problem.
• 6mm panels may require a deeper frame rabbet or special mounting hardware. They also look a bit more substantial if displayed unframed.

Cost Considerations

It’s no surprise that 6mm panels cost more than 3mm. They use more material and a more complex honeycomb core. For artists on a budget, it often makes sense to use 3mm panels for studies, smaller works, or travel, and reserve 6mm panels for major projects or commissions.

Think of 3mm panels as your everyday workhorses, and 6mm panels as your heavy-duty option for when the stakes are higher.

Comparing Artefex panels to Other Brands

How do Artefex panels stack up against alternatives?

• Wood panels (like Ampersand Gessobord): These are often 1/8” thick like the 3mm Artefex, but wood is prone to warping over time. Artefex’s aluminum composite is far more stable.
• Raw aluminum sheets: Some artists prepare their own aluminum, but Artefex saves you the hassle by bonding fabric and applying archival grounds with professional precision.
• Cradled wood panels: A 6mm Artefex panel can replace the need for a cradle. It’s one solid piece with no wood joinery to shift or warp.

Artefex essentially offers the reliability of aluminum with the feel and surface preparation artists expect.

Final Thoughts: Which Should You Choose?

Both 3mm and 6mm Artefex panels are excellent, archival, and designed to last. The right choice depends on how and where you paint:

• Choose 3mm if you work small to medium, paint plein air, want lightweight surfaces, or need panels that fit easily in frames.
• Choose 6mm if you work large, apply heavy layers, need absolute rigidity, or want panels that can stand alone without bracing.

Many artists end up using both: 3mm for studies, travel, and regular studio work, and 6mm for their largest or most important projects.

At the end of the day, either option gives you something priceless: peace of mind that your painting will stay flat, stable, and protected for generations.