21x56 3D Pro 3.5" Deep K3 Stretcher Frame Kit

True 8:3 Custom Proportion - 21x56 Size

Explore other sizes in this same 8:3 aspect ratio:

15x40 • 24x64 • 33x88 • 39x104 • 42x112 • 45x120

• Super strong 3D™ Pro K3™ Stretcher Bar is a very popular among contemporary artists whose painting will be displayed without a frame.
• For this 21x56 large size frame, the frame provides the ultimate foundation for your art with increased strength and stability
• Provides a 3.5" deep stretched canvas which makes a bold and commanding display
• 1-1/4" wide Stretcher Bars
• All Bars have an exclusive groove on the inside perimeter of the frame to which cross braces and Diamond Corner Braces attach
• Solid Ponderosa Pine or Fir from the Pacific Northwest

3D™ Pro 3.5 Stretcher Bar • 1/2" Canvas Clearance

1/2" Canvas Clearance is the space between the Bar and the canvas. Generally speaking, more clearance reduces the risk of the canvas touching the wood and creating unsightly lines during painting. Our design provides the optimal clearance so as not to impact your painting, but still leaving enough wood to the maximize strength of the Stretcher Bar.

• Produces a 3.5" deep stretched canvas (Actual depth is slightly thinner)
• 1.25" wide Stretcher Bar
• All Bars have an exclusive groove on the inside perimeter of the frame to which cross braces and Diamond Corner Braces attach
• Solid Ponderosa Pine or Fir from the Pacific Northwest

No Finger Joints!

Solid Wood is far superior to finger jointed wood, which is many small pieces glued together, each with varying grain densities that absorb and shed moisture at varying rates, expanding and contracting non-uniformly as environmental conditions change, and causing the wood to bow and the finger joints to eventually fail.

A single homogeneous kiln-dried solid wood Stretcher Bar outperforms and outlasts a finger jointed Bar whose sole purpose is to save the manufacturer cost, not contribute to the archival value of artwork intended to last a millennium. As a manufacturer, Masterpiece® does its part to conserve as much wood as possible, and still provide a quality product that will out-perform any other in the marketplace.

Sustainably Managed Forests Coexist with Mankind

We use lumber grown in the sustainable forests of the Pacific Northwest, where thereÕs more standing timber today than last century! There will always be a demand for wood pulp and fiber, but striking a harmonious balance with human coexistence is the essential strategy to which we subscribe. Sustainably managed forests increase our health and abundance of our forests which can be in harmony with this precious natural resource.

Specially Dried and Heat Treated Lumber

We source our wood from a select group of top-tier environmentally conscious lumber mills in the Pacific Northwest. These mills specially dry and heat-treat the lumber to our specifications, resulting in about half the moisture content compared to wood from typical home improvement centers or lumber yards. This process makes the wood stronger, reducing the likelihood of cracking, splitting, or warping. While the wood we use comes at a higher cost, it ensures a more dimensionally stable end product. This stability is crucial for crafting fine professional canvases that support your invaluable art over time.

31x66 is the Canvas Size Needed for this 21x56 Frame

Please note that you will need a canvas that is at least 10 Inches larger than the actual frame size to ensure proper stretching. This will provide ample material to stretch the canvas and attach it to the back of the frame. If you prefer to attach the canvas from the edge of the stretcher frame, you can reduce the size of your canvas by approximately 3/4" all the way around the frame. This will allow you to paint on the edge of the canvas and hang your artwork without needing a separate picture frame. And, if you ever need to remove the canvas from the frame and re-attach it, you'll have enough material to do that too.

Tight'n'Up™ Liquid Canvas Retensioner

One of our most appreciated products helps make your canvas tighter! Stretching a canvas tightly can be a challenge. Our Frame Kits include the Corner and Brace Keys that you will need to add tension, but Tight'n'Up™ Liquid Canvas Re-Tensioner is a way that you can use to add tension to the canvas without needed to use the keys. It canvas be sprayed on the back of a canvas to repair most canvas tension issues.

With Tight'n'Up™, you can add tension to just a small area, or a large area. Simply spray it lightly on the back and brush it into the canvas, and within seconds, your canvas becomes tighter and stays tighter. The more you use, the tighter it gets. Recommended for acrylic primed cotton or linen canvas. We do not recommend it for oil primed canvas because there are simply too many different types of oil primed canvas, but used conservatively at your own risk, it will tension any canvas.

Rooted in California and flourishing since 1965, Masterpiece® takes pride in its family-led legacy of crafting North America's premier Stretcher Bars. Our quest for excellence isn't just a goal but a commitment, positioning us as the trailblazers in the domain of fine-art canvas. Our innovative patents have set new benchmarks, ensuring our offerings stand unmatched. Dive into the tactile experience of our products, and you'll instantly recognize the distinct Masterpiece® quality, a signature appreciated by both your clientele and future art connoisseurs.