Tag Archive: riveting

Watertight riveting in kayaks and boats

Updated October 6, 2017

Pop rivets are widely used in the construction of boats, canoes, and kayaks.
Sealing rivets can be useful as a measure of extra precaution in case they come in contact with the water through which your kayak or boat goes.

How to better seal the rivets

Here are some tips for watertight riveting of kayaks and small boats made from Polyethylene –

  1. Polyethylene is the most widely used polymer resin (namely “plastic”) in kayaks, and it’s softer than aluminum and fiberglass used to produce other small boats. For this reason, it is recommended to use special aluminum rivets designed for riveting jobs in kayaks. These special rivets split in three, which increases their grip on the surface around the rivet. You can get these rivets in outfitters stores, and online.
  2. Drill holes of exactly the same diameter of the rivet that you use (3/16″), and preferably slightly smaller holes (5/32″).
  3. Apply a dub of Goop adhesive on the hole, and push the Goop into the hole. Goop is a powerful watertight adhesive used for plumbing and marine projects. The Goop you squeeze into the hole will coat its sides, and come out on the other side.
  4. Before you insert the rivet into the hole, coat its end with Goop. As you push the rivet into the hole, its tip will come out on the other side, and it will be coated with a thick layer of Goop. The sides of the rivet will be coated with Goop as well.

    A rivet dipped in Goop watertight adhesive

    As you pull the rivet’s mandrel, the rivet will split in three and it will attach the two plastic walls while being coated with Goop. Excess Goop that will not come out on the other side or coat the sides of the hole, will remain on the outer surface and get squeezed by the rivet’s head. This way, the rivet’s parts that come in contact with the plastic will be coated with Goop, which will make them watertight.

  5. After you’re done riveting, coat the rivet’s head and the surface area around it with a generous amount of Goop. This will prevent water from touching the rivet, and in case of saltwater, it will prevent corrosion.

Aluminum rivets in fishing kayaks and boats

You may have an outfitting project in mind, such as attaching a rod holder to your kayak, or you may just wonder how strong are Wavewalk kayaks and boats built.
More generally, how well do aluminum rivets work when used in kayaks?

Before going further, we need to explain that nearly all modern kayaks are made from Polyethylene, a polymer (plastic resin) softer than steel and aluminum, and even softer than fiberglass, which is why it requires the use of special rivets that split in three and provide a better grip over a broader surface.
These rivets go under commercial names such as Tri-Fold, Tribex, etc.

Alumium rivets are used for attaching kayak parts together, such as the 14 rivets that attach the W700 Saddle part to the Twinhull part.
They are also used for attaching accessories such as handles, pad-eyes (eyelets), etc.

Here is a little experiment we did –

We riveted together two pieces of Polyethylene that we cut from a part of a Wavewalk kayak. We used just one rivet for this.
We hung one end of the joint pieces of plastic from a basketball pole, and on the other end we hung a fish scale.
We hung a travel bag from the fish scale, and filled the bag with bricks.
We stopped after ten bricks, because the dial on the fish scale had ran full circle, and stopped at 50 lbs.
At this point, neither the plastic pieces nor the rivet showed any sign of stress.




Needless to say that the effectiveness of a rivet depends on more than just the force applied on it in lbs, and additional factors are very important, such as the angle of the force (vector), leverage (a critical factor), the temperature of the plastic (hot plastic is softer), etc.
If we had attached the parts in this experiment differently, we would have seen different results.