Background:

We wanted to add LED light caps to our deck posts. We have numerous posts that are the Radiance Rail model. Running electrical wire would be easy, but hiding the wires and accommodating our waterproofing needs wouldn't work well for us.

Enter solar light caps, which can be found at various online retailers. We went with a brand called Aponuo, and they work very well. They have good battery life overnight and provide enough ambient lighting. However, the adapters to fit our posts were not visually appealing to us.

What It Is:

We created a deck post cap that matches our Radiance Rail. This is a two-piece print: one cap and one adapter are needed. The first piece is the cap, and the second piece has multiple adapters. Only print one adapter per cap (or print a few extra, if needed). This deck post cap is a snug, friction fit on our deck posts and provides a secure twist-lock connection for the Aponuo solar post cap lights.

Outdoors:

We printed everything in PETG and have had no issues after 6+ months of exposure to direct sun, rain, snow, hail, 70 mph gusts, etc. These caps are a tight fit to resist blowing off in the wind. They’re tight on purpose! In some cases, if the post has been in the sun, it may be easier to place the cap on at night or after the post has cooled. The heat from the sun will expand the post and may make the cap harder to install, but again, that’s by design so that the caps don’t need to be permanently attached with glue, yet still remain secure.  We attach the cap to the post first, and then twist on the light second.

Print and Assembly:

Print as many caps and adapters as you need in PETG. After printing, both pieces need to be secured to one another. This is also a friction fit. Place the adapter on a hard surface, preferably granite, stone, or a similar hard countertop. The prongs of the adapter should face upward. Next, take the cap and line up the prongs of the adapter with the four holes in the cap. Push down evenly to get each prong started. Then, apply firm pressure or a quick burst of pressure to one area of the cap near one prong. Continue this process one push at a time in a clockwise or counterclockwise direction for each prong. There's no need to fully secure one prong before moving on to the next. Just push once, move to the next prong, push again, and repeat until all prongs are secured. This may sound complicated, but it’s quite simple once you’ve done it. We’ve done it about 36 times now. :)

Once assembly is complete, the Aponuo light should be able to twist on or off.