TRI-MAR HAS BEEN MAKING STRETCHERS FOR ARTISTS IN THE NEW YORK TRI-STATE AREA FOR 35 YEARS.
In 2015, we designed and engineered an aluminum stretcher bar system with the same tongue and groove assembly as a standard wood stretcher. Our patented, aluminum bars cannot warp or twist and are 100% keyable in the corners and cross–braces. Follow our simple stretching instructions and your bars will always lay flat against the wall.
Aluminum Stretchers
Custom Sizes
Custom Shapes
Custom Wood Panels
Stretching Services
We have a list of sizes of Series #1 aluminum bar (1” deep) and our #3 aluminum bar (1.25” deep).
We can make any size you need. Pricing for custom sizes is the same as our stock sizes. We do sell individual bars as well. They are not listed to ensure each set has the proper cross–bar arrangement for your order.
If you do not want cross–bracing just indicate in the Custom Order section of our website.
HOW TO STRETCH CANVAS ON OUR BARS
Our bars cannot twist or warp, but you can still over–stretch. The number one cause of warping is over–stretching raw or pre–primed cotton.
The number two cause is weather, specifically humidity.
How to avoid overstretching raw cotton
Stretch tight, but not tight enough that the bars begin bowing or inflecting. Your first coat of gesso will tighten up a lot! As the gesso dries the tension of the canvas will lessen. Loosen the top screw of steel plate that joins the crossbar to the perimeter.
Insert one crossbar key into the designated slot where each crossbar attaches to the perimeter bars. Tap keys in gently. Continue priming. When finished you may remove and reuse keys, or leave them in.
Stretching gesso primed cotton
Stretch taut, but not tight. Loosen top screw on each steel plate that joins crossbars to perimeter bars. This allows the bars to expand.
Use crossbar keys to tighten canvas for painting. Additional layers of gesso will cause the surface to continue to shrink. Remove keys when done and remember to retighten screws.
Stretching pre–primed linen or poly–cotton
We consider this the best surface to paint on. Primed poly–cotton and linen are less elastic and most stable to paint on. They do not have the shrinking factor of cotton and will not be as affected by humidity. We highly recommend primed poly–cotton
over gessoed cotton canvas. Poly–cotton is also very economical. Stretch as tight as possible and key out as needed.