Spine is a thin cord made of vinyl or foam that hold the solar screen material to the screen frame. The solar screen material is laid across the screen frame's spline track. The spline is then laid over the screen material and 'rolled' into the spline track, trapping the solar screen material between the spline and the spline track. When the proper sized spline is use, the solar screen material is held firmly in place and will not come out.
Vinyl and Foam spline are both durable products that work equally well. Ultimately personal preference determines which type of spline to use. One screen professional will tell you they only use vinyl. Another will tell you they only use foam. There is a little more flexibility with foam spline when it comes to the size of spline to use. Foam spline can be compressed more than vinyl spline, so a larger diameter foam spline can be used in several situations where a the same sized vinyl diameter spline would not fit.
Spline measurements are for the diameter of the spline and the measurement is typically in inches (i.e. .125' is a common spline size, and represents 1/8' diameter spline). Some typical spine sizes are:
We have a helpful spline size guide for quick reference when checking what size spline is needed for a project.
Window Screen Resource Center
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