For most mariners, the joy of spring launch is short lived once the chore of preparing one's vessel and paying for it all arrives. Removing winter covers, painting, buffing, polishing, pumping, repairing... Didn't I buy this thing to relax?
This is when most of the canvas repairs flow into my shop. In the early season, re-stitching, zipper replacement and window replacements are the most common repairs on the "To Do" shelf. And while every customers always asks, "How much will this cost me?" Their next question should be, "How can I prevent this from happening again?"
The answer is simple- Keep it out of the sun.
Window Covers- Isinglass windows have an average lifespan of five years in direct sunlight. UV rays break down the plasticizers in the PVC vinyl surface leading to yellowing, charing and cracking. Installing snap down canvas window covers over the outside of the isinglass will double, maybe even triple their life span. They also reduce the greenhouse heat effect inside the enclosure and will shade the interior vinyl seating preventing them from fading and cracking as well. Do the math. The cost of window replacements every five years as well as upholstery repairs far exceed the cost of window covers. Additionally, regular cleaning and the use of a UV inhibitor such as 303 Aerospace Protectant is highly recommended.
Cover All Zippers- When having a custom canvas top and enclosure fabricated insist that the zipper teeth are hidden from the sun beneath the canvas flap. Zippers are made of nylon which is very vulnerable to UV damage- cracking and sun bleaching. You may have noticed that after a few years the black nylon zipper teeth and tape is bleached to light grey. Same holds true for velcro which is often nylon. Even the more durable poly velcro will quickly fade. Keep it out of the sun.
UV Protected Thread- Whether having a new top made, a re-stitch or repair, make sure the fabricator uses a UV protected thread such as Sunguard- polyester. Many upholstery shops use nylon thread for interior work, which is very durable for interior applications, but if they use the same thread to re-stitch your bimini top you can count on your stitching sun faded and tattered in a couple seasons. Beware of the part time yahoo's that flood the marinas in spring looking for a quick buck with little knowledge of boating or canvas work. Ask if they'll make a new bimini top enclosure and if they can bend a camper back frame? If they only do quick, little jobs, you'll be far better off finding a professional marine canvas expert who will use the proper materials and be there throughout the season to guarantee their work. If you want your stitching to last as long as the top, Tennara thread, with it's lifetime warrantee, will actually outlast the canvas.
Clean, Re-Seal- Dirt embedded in canvas or vinyl will help break the material down and is food for mildew. It doesn't grow on canvas. It feeds on the dirt and other particles embedded in it. Keep it clean and re-apply a sealer such as 303, every couple years and you may avoid paying for a new one.
Winterize Removal- Do not leave the canvas on underneath the winter cover during winter drydock. Especially if the winter cover touches the canvas, which is very vulnerable to chaffing. It's best to clean it and keep it dry indoors and store the isinglass windows clean and flat with cloth between them . Cold vinyl will crack on a fold and particles may embed in the vinyl. Flat storage impossible? Roll the panels very loose and big, separated with old clean sheets or towels. Tie the rolls to keep them from unraveling and store them standing upright. Never lay rolled up eisenglass flat! When Isinglass touches itself for an extended time a "pooling" effect occurs. But if you do forget to put soft cloth between, don't despair. The pooling distortion will disappear in the hot sun.
Don't Trailer- Unless it's a proper mooring or trailering cover- having webbing loops along the bottom to tie down- don't trailer the boat with the canvas up. Your expensive bimini enclosure wasn't designed to barrel down the interstate at 70 mph.
Unfortunately, even the best fitting professionally made custom boat top will eventually wear out. But there are many things a boater can do to prolong the life of their canvas and isinglass. And while many people regard their canvas as something that protects their boat from the rain, the sun's UV rays are responsible for most of the damage to the upholstery, canvas and isinglass.