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Splines for Reinforced Aluminum Handrail



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Clean, Concealed Joints for your Aluminum Handrail

Join your aluminum handrail sections using a combination of fixed and adjustable splines. Once installed, all splines are concealed giving your handrail and clean, continuous look free of brackets or cover plates. Furthermore, each aluminum spline creates a structural joint that does not need to be supported by a post, allowing you to span further with fewer posts.

The following splines are designed exclusively for Cable Bullet aluminum handrail.

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Structural, Fixed or Flexible Options for Any Handrail Configuration

Fixed Splines

Fixed splines are available for level, 90-degree corner transitions, as well as straight runs. For irregular or custom bends in your railing, spline stock can be used to create any transition.

Fixed Straight Spline (Structural Aluminum)

Use these 4-inch long structural aluminum splines to quickly piece together two or more lengths of a handrail along a straight run to create a structural joint. Joints using the structural aluminum spline do not need to be supported over a post! This allows you to join pieces of handrail to form one continuous run without needing to worry about the placement of your structural support posts, reducing waste and time spent cutting custom lengths.

In combination with our reinforced aluminum handrail, these splines allow you to extend your structural post spacing 7-9 feet apart with minimal deflection under load.

Fixed Corner Spline

The fixed corner spline is made from Delrin, weather and UV-resistant exterior-grade plastic, and is designed for use at any level, supported corner transition. All Delrin splines are slightly oversized by design and may require a rubber mallet or dead-blow hammer to set in place.

18-Inch Spline Stock

Delrin plastic spline stock is available in 18-inch sticks and is intended to be cut down on-site and modified to create any non-standard, horizontal transition, e.g. a 45-degree turn in your railing. Use a miter saw and deck screws as needed. One 18-inch stick is sufficient material to make up to 3 splines. Any custom Delrin spline should be supported by a structural post. Use 2-1/2-inch #9 decking screws to connect spline pieces.

Adjustable Splines

Adjustable splines are designed to simplify handrail construction around stairs, and complex angles or transition points. Use adjustable splines anywhere your handrail breaks from a level to an angled run. Each spline will pivot up or down to match the rise of your stairs.

Adjustable Spline Options:

  1. Adjustable straight splines include two interlocking end pieces that pivot on a hinge pin. This spline can be used anywhere a level straight run continues into an angled run, or where a stair handrail levels out.
  2. 90-degree splines have two additional lap joints that form a corner piece. Use this spline on inside corners around stairs and landings.
  3. 180-degree splines include two end pieces and four lap-joints to create a u-shaped spline. This spline is designed for handrail connection points that require two pivot points, e.g. on the inside railing between two flights of stairs connected by a landing.

All aluminum splines are machined from heavy-duty type 6061 aluminum. If necessary, use a structural epoxy to permanently fix your aluminum or Delrin splines inside the handrail. You may also use a #9 - 3/4" stainless steel sheet metal screws to secure any spline through the underside of your handrail.