Boat canvas sewn with polyester thread needs to be checked out a couple times a year. Recognizing when to get your boat curtains, boat tops, and covers to the canvas shop can save you a lot of money. If left to long without re-stitching, your curtains and other canvas can break down, fall apart, and cause even more damage to your boat. A few examples would be scratching your clear vinyl, breaking your zipper teeth, and worse. A curtain flapping in the wind can cause damage to your gelcoat or even unprotected electronics.
Depending on your location and UV exposure, you can start looking for thread failure from 2 to 4 year old curtains. So here is what you look for; – – – – – – – – – Just one (1) missing stitch! That one stitch that’s missing is the very beginning of what’s to come. Usually on the sunny side of the boat or the top that’s facing straight up. When you see that one missing stitch it’s time to get it to the canvas shop and re-stitched.
The best alternative to regular polyester thread is a PTFE type thread like Tenara, Gortex, or SolarFix. This thread is usually guaranteed to last as long as the canvas it’s sewn into against UV degradation. PTFE thread is not initially as strong as polyester when first sewn, but as polyester slowly breaks down from UV exposure, the PTFE thread remains the same strength. This threads cost is about four (4) times the cost of polyester but the labor cost should be the same. Just ask your canvas shop the difference in price. Some shops only use the PTFE thread. The great thing about using this thread is that you won’t have to worry about it again.
If you have a laced top, you will have to remove all electronics to have it re-stitched, so plan ahead! Anytime you have your antennas, lights, GPS, or radar worked on, check out that canvas top. If your top is 5 years old with polyester thread, just get it re-stitched.
Once again, just look for that missing stitch and take care of your canvas then.