Parts of a Spline Roller

A standard spline roller consists of a wooden handle with a metal wheel on each end. The wheels appear identical at a glance, but close inspection reveals that one has a thin edge grooved outward (this is the convex wheel) and the other has an inward-grooved edge (this is the concave wheel). The convex wheel is only used when installing metal screens. This pushes the new screen into the channel of the screen frame before you install the spline, pre-shaping the screen inside the channel so the spline will go inside willingly. The concave wheel is used to press the spline—with the screen beneath it—into the channel. With a fiberglass screen, you can do this in one motion; no pre-shaping is necessary.

What Spline to Use

Spline comes in several different diameters, from 9/64 (0.14) inch to 7/32 (0.21) inch. If the replacement screen is the same type as the old material, use the same spline size as the original. If the new screen is thicker than the old screen, choose one size smaller for the spline. It’s helpful to bring a piece of your old spline to the hardware store with you to compare different sizes until you find the right option.

How to Use a Spline Roller

If you’re repairing the screen on a sliding door, you’ll need to remove the screen door before replacing the screen and spline. Always cut the new screen to size first, leaving it a few inches larger than the frame. If you’re using a metal screen, it’s important to pre-fit the screen into the frame channels before adding spline (this step is not necessary for a fiberglass screen). Lay your metal screen over the door or window frame and use the convex wheel of your spline roller to press the metal screen inside. Once your screen is prepared, it’s time to install the spline as you would with fiberglass screen in the steps below.

Keeping Spline Rollers Clean

Since spline rollers are rarely used in most households, their wheels can develop buildup from being stored in toolboxes or drawers that collect dust. If your spline roller’s wheels begin to stick, simply rinse it off and wipe it down with water or a degreaser like WD-40. When using water, dry metal wheels afterward to prevent rust.

When to Replace Your Spline Roller

Some spline rollers have plastic wheels that can become cracked or damaged over time. Once one of the wheels is cracked, the tool will not function properly. Thankfully, spline rollers are typically affordable, and a new tool can be purchased at most hardware stores.