We help people repair plastic
Sea-Doo Polytec Hull Repair
Bombardier Recreational Products, or BRP, has introduced several Sea-Doo personal watercraft with a new hull material they call “Polytec”. Polytec is a glass fiber reinforced polypropylene material that is much lighter than the typical fiberglass or SMC that is used to make watercraft hulls. The lighter hull material allows for easier trailering and great performance using a smaller engine. Sea-Doo has expanded the use of this material across its line to include SPARK, WAKE, GTR, and GTI models, and likely more in the future. If the Sea-Doo hull is black and the upper and lower parts are bolted together, it’s likely that the hull is made of Polytec.
Sea-Doo’s Polytec material is tough thanks to the glass fibers embedded in the polypropylene material, but it is not indestructible. The hull can be cracked and broken if struck with sufficient force. Needless to say, replacing a cracked hull can be an expensive proposition. But with Polyvance’s products and techniques, you can make quality repairs that will save you thousands of dollars.
The cost of a new Sea-Doo Spark hull (at the time this page was written) is $1,750! Add in the labor that the dealer will charge, and you could easily spend $3,000. Polyvance's products can save you a lot of money. Not only that, but in the event you happen to get another crack in the hull, you will already have the tools you need to repair it again! Surely, you have some friends with polytec hulls, too. (After all, it's pretty boring riding by yourself.) They would probably pay you to fix theirs!
You need to clean the damaged area of any contaimates that could cause problems with the repair. Clean the damaged area with Polyvance's Super Prep plastic cleaner, or Polyvance's EcoPrep plastic cleaner. Spray a heavy, wet coat and allow a few seconds for the cleaner to soak into any the dirt and grime, then wipe with a clean cloth or paper towel.
On this particular crack, the impact distorted the plastic and the crack was misaligned. Use a heat gun to soften and "relax" the plastic. Don't rush this. When the plastic gets hot to the touch on the opposite side, use a rounded tool to push the crack into alignment. We used a screwdriver handle for this.
Apply aluminum tape to the outside of the hull along the crack line. The tape keeps the crack aligned and it will prevent the weld from blowing through the crack when you're welding from the inside.
On this particular crack, there was a little bit of residual stress on the crack that the aluminum tape was not able to hold in alignment, so we inserted a few staples with Polyvance's Hot Spot Plastic Stapler. You may not need to do this if the aluminum tape is sufficient to keep the crack aligned.
With a die grinder and a cutting bit, grind a v-groove about halfway throught the plastic. Make the v-groove fairly wide... about a half inch (1.25 cm). You want to make sure there is plenty of contact area between the welding rod and the hull.
Use a plastic welder to start laying down a bead right down the middle of the crack with the "02" profile rod. We used Polyvance's nitrogen plastic welder for the repair, but for the Do-It-Yourselfer, you may want to consider using our hot air welder (without the nitrogen). Note that the welder nozzle is very close in to the work, and that the hot nitrogen gas is melting both the hull and the welding rod at the same time. Apply a light downward pressure to the welding rod as you make your pass to fuse the two plastics together. When you reach the end of the pass, direct the heat on the rod alone for a few seconds, then twist the rod to break it.
Because the v-groove is so wide and deep, this repair will take several passes of welding rod to fill completely. Here we are welding with the "05" profile wide ribbon.
Now that the rod is laid into the groove, we will use the airless plastic welder to smooth it out and burnish it in. Note that we are using the nitrogen (or hot air) plastic welder to preheat the plastic immediately ahead of the airless welder’s tip. Move the tip slowly over the surface and let the heat do the job. Keep the heat on the plastic and smooth it with the airless welder to your satisfaction.
You may skip this step if you didn't use the staples. After letting the weld cool completely, we will remove the temporary staples by reheating them with the plastic stapler and pulling them out with a pair of needle nose pliers. After the staples are removed, we will v-groove the area as we did before and weld that segment of the hull using the same method.
Peel away the tape from the outside and get it ready for repair. We reused the aluminum tape and applied it to the inside to help support the area while we weld on the outside.
Clean, v-groove, weld, and smooth the cracks on the outside of the hull just like you did on the inside of the hull. Allow the plastic to cool completely and sand it smooth. You may find that you have some low spots that you need to fill in. If so, fill them in, wait for it to cool completely, and continue sanding until everything is smooth.
After sanding, the plastic will look hazy and a little bit fuzzy. Get a propane torch and QUICKLY go over the surface. This will melt down the tiny sand scratches and flow out the plastic to give a slicker finish.
When finished, it should look something like this. Congratulations. You just saved thousands of dollars.
This page was created on September 20, 2022
seadoo polytec hull repair sea-doo spark hull repair