1/4 Inch Spline
Solid vinyl spline cord feeds into the rail channel of your patio frame to lock the sling in place. Sold by the foot, cut to the length you order. Match your existing spline by measuring the diameter, or pull a few inches of the old spline out and bring it to a hardware store with a caliper if you're not sure.
Vinyl spline (also called sling rod, sling cord, or sling spline) is the solid PVC cord that locks the edges of a replacement patio sling into the rail channels of an aluminum or wrought-iron chair, chaise, or ottoman frame. Without spline, even the toughest Sunbrella, Phifertex, or Textilene sling fabric will stretch loose and pull free of the frame within a season. Every patio sling replacement job needs new vinyl spline; the old material gets brittle, cracks, and shrinks in the channel after a few summers in the sun.
Spline diameter has to match the rail channel on your frame. Two common sizes cover the patio chairs, chaise lounges, and ottomans we make replacement slings for:
Both sling spline sizes are sold here for $1.25 per linear foot, cut to the length you order.
If you aren't sure which spline size your patio furniture takes, pull a short section of the existing spline out of the rail channel and measure its diameter with a caliper. Drill bits also make an excellent reference: line the old vinyl spline up against a 1/4" and 5/16" bit and pick the closest match. When in doubt, send us a photo through our contact page and we'll identify the size for you before you order.
Measure the total length of the rail channels on your frame that hold the sling, then add a few extra inches for trimming. As a starting point, most replacement patio chair slings use about 5 to 7 feet of vinyl spline per seat. Replacement chaise lounge slings typically need 10 to 14 feet per chaise. Ordering a foot or two extra is cheap insurance and gives you room to cut cleanly without splicing the spline mid-channel.
Sling spline is much easier to install when it is warm and flexible. Set the coil in the sun for 20 to 30 minutes, or run warm tap water over it just before installing. With your new sling fabric pushed into the channel, work the spline in behind it a few inches at a time, pressing it down with a flat-blade screwdriver wrapped in a rag, or with a rounded wooden dowel. Trim flush at each end of the rail channel with a sharp utility knife.
We recommend installing new vinyl spline every time you replace a patio sling. Reusing old, brittle spline almost always causes the fabric to pull loose within a few weeks, and old spline often cracks during installation. New spline paired with a custom replacement chair sling, chaise lounge sling, or ottoman sling sewn from our marine-grade outdoor sling fabric selection gives you the longest-lasting result.
Both vinyl spline sizes (1/4" and 5/16") are $1.25 per linear foot, cut to the exact length you order. Sling spline ships separately from custom replacement patio slings and typically arrives within a few business days.