Frequently Asked Canvas Care Questions

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Boat Covers
If the cover is a coated fabric, regular rinsing with fresh wash is normally all you need to do. To remove dirt and bird stains, use a mild detergent and soft bristle brush. Do not use harsh cleaners or brushes, since these will shorten the life of the fabric coatings. If the coating is a woven acrylic material such as Sunbrella, see above for the latest cleaning recommendations.

Vinyl Windows ("Isinglass")
Vinyl windows are very expensive. Cared for properly, you should get years of service from them if they were good quality to begin with.  The most common signs of degradation are crazing or cracking, discoloration or cloudiness, brittleness, or surface chalkiness. When they start to go, they go fast! 

Why is this? From the moment it is made, vinyl constantly "evaporates" plasticizers from the surface.  Over time the vinyl exhausts it's internal plasticizers, dries out, discolors, and finally becomes brittle. Damage is hastened by contact with liquids such as harsh cleaners and polishes. Polishing at this point has limited value in restoring the window- it has literally dried out from the inside. 

Proper care is essential to long life. This includes regular rinsing of salt spray and debris, periodic cleaning with a soft cloth (no paper towels), mild detergent, and warm water. Heat and harsh UV (sunlight) exposure hasten deterioration significantly. Never use any kind of product with silicone in it on your windows, and don't handle the glass with sunscreen on your hands. 

Today's best marine vinyls have top coatings to reduce plasticizer migration, but the top coatings need to be preserved to do their job. The best prevention is to avoid scratching, rubbing, or folding the windows as much as possible, to avoid harsh chemicals and brushes that destroy the top coatings, and to periodically restore the protective film with a recommended product.  

Keeping the windows under cover, whether a whole boat cover or individual snap-on covers, can extend their life considerably. If your boat's vinyl windows will have full exposure for long periods, an investment in canvas window covers will pay back many times over. 

For non-Strataglass vinyls, regularly applying a specialty vinyl protectant like one of the 303 Aerospace products, Plexus, or McGuiars will help.

Strataglass/Crystal Clear 20/20 vinyls are different! As of 9/30/04, the Strataglass company requires use of specific IMAR cleaning and polishing products to maintain the warranty. Aquatech and Collinite products are no longer recommended. 
See new Strataglass instructions here.

Zippers, Snaps, and other fasteners
Zippers, snaps, and other fasteners carry strong loads. The less stress placed on them during normal operation, the less frequently you’ll have to replace or repair them.

Fasteners should be unsnapped by pulling as close to the fastener itself as possible. Don't remove canvas by jerking one edge of the material. This can damage the canvas as well as the fasteners. 

If fasteners become difficult to work, lubricate them with a commercial product such as Star Brite, IOSSO, etc. These products contain special ingredients like Teflon. Or, you can get by short term with Vaseline, WD-40, silicone spray, even ChapStik...!!  

Whichever  product you use, be sure not to contact the canvas or any other surface besides the fastener. Silicone will damage the water-repellent coating on Sunbrella, for instance, and it is terrible for your vinyl windows. Broken or missing fasteners can usually be fixed with the proper tools and parts. These can be obtained at West Marine, BoatUS, Sailrite Enterprises, a good marine chandlery or hardware store, even Home Depot in a pinch. For larger/tougher jobs, a canvas shop has the industrial-grade materials and tools of the trade to take care of you.

What's the best way to store my canvas items?
If your canvas is not going to remain on the boat all season, it's important to spend a minute to store it properly. Three main rules: Clean, dry, and no creases! Clean the canvas and vinyl windows as outlined elsewhere in these pages. Even though synthetic fabrics themselves don't support mildew, humidity combined with chemicals in the air and organic growths on the surfaces can lead to mildew, mold, stains, marks, and worse... even ruining canvas in a single season. And vinyl windows can stick together, or take a pattern from another surface. So clean first, dry thoroughly, store in a well ventilated area. Try to store large panels flat, with sheets of paper or fabric between the panels so they don't stick together. It is OK to roll a top or dodger, but watch those creases & folds! 

Can I do some canvas repairs myself?
Yes you can. First,  you can help avoid repairs in the first place by following a regular maintenance program. Doing so can nearly double the useful life of your expensive canvas items. Second, stay on top of small repairs before they become big. For instance, stitching that is beginning to deteriorate or pull apart can sometimes be fixed short-term by careful use of a home sewing machine and proper materials. 

Fastener replacement and small sewing projects can also be very satisfying if you have the time and patience. An excellent source of materials and advice for the interested or adventurous is Sailrite Enterprises. Major repairs to your canvas or covers are usually best left to a professional canvas repair shop. A good repair shop has the industrial-strength machines, materials, and experience needed to make these repairs cost-effectively for you. If you aren't sure, call us and we can discuss it with you.

How long will my new Sunbrella® canvas last?
With proper care, six to eight years seems to be the reasonable limit in the Bay Area with our cycles of heat, cold, wind, and rain. If you replace worn/broken fasteners regularly, have the top restitched if/when needed, and keep it clean, you will get maximum life. Less than good care and hard use will reduce the lifespan of your canvas significantly. 

The stitching usually goes first, because it is exposed to abrasion, constant tension, flexing, pollution, sunlight UV rays, water, cleaning agents, and being snagged with sharp items. You should check the stitching periodically by rubbing it with your fingernail in a high-wear area. If the stitching starts to fall apart, have the item restitched promptly. Once seams begin to loosen and part, the fabric will lose it's shape and become difficult and expensive to salvage. One option to extend thread life is to use a Teflon (PTFE) thread like Gore-Tex Tenara (see next answer).

Proper tension and fit is also important- baggy, loose, or torn tops that flap in the wind wear out much faster. Mold, moss, and mildew from poor ventilation can also do much damage in a short time. 

How can I avoid the cost of re-stitching every few years?
Regardless of material quality and craftsmanship, the thread is usually the weakest link in the durability of a canvas product. At some point, perhaps around halfway through the life of the canvas fabric, the stitching will need to be re-done. The goal is to hold this off as long as possible, or even avoid it entirely. There are two basic approaches to this.

The best conventional solution is to use the very best available UV-stabilized, smooth bonded polyester marine threads in a heavy weight, such as 138. Combined with good construction techniques, these can give very good service, sometimes lasting the life of the fabric itself in mild environments. These threads have a high initial strength factor, great variety of colors, are reasonably priced, and work well in the fabrication process.

Alternatively, there are high-tech PTFE threads (PTFE is  commonly known by the DuPont brand name Teflon®) like Tenara® and Profilen. These are guaranteed to last the life of the fabric in which it is used. Compared to the best bonded UVR 138 poly threads, PTFE thread is quite expensive, doesn't come in as many colors, can be tricky to sew with, and is not quite as strong as heavy-duty poly thread when both are new. But after a few years, the poly thread loses much of it's strength, while PTFE thread stays as strong as new. Thus, if you plan to keep your boat for 4+ years, it can be a wise investment. PTFE thread is about 10 times the cost of poly thread, and will add to the cost of the job, but it can pay for itself several times over. We recommend and use Tenara and Profilen for those who would like this alternative. That's part of our discussion about your canvas project.

Can't I just buy a pre-made Bimini or cover?
Yes, pre-made covers and tops of several types are available from marine stores, mail-order, and Internet  vendors. Some of these (like sail covers, dinghy covers, etc.) may be acceptable if your boat is a common make & model, you have made no changes and added no equipment, don't need to match existing canvas, don't have any specific requirements, and are on a strict budget. 

However, these products are generally mass-produced with inferior fabrics, hardware, and construction, and are not really built to last. Knock-off copies of brand names like Sunbrella and YKK are common. They are also generic in fit, even by specific model & year, so they often don't look right despite your best efforts. We see many of them fail within a year, and they aren't worth repairing. They are made to a price; after all, that's what you were looking for, right?!

 Actually, the best pre-made covers & tops can approach the cost of a custom job. If the budget is a concern, discuss it with your local canvas shop; they may well be able to work with you to make that "just for you" job surprisingly affordable!

Can you just copy my old canvas piece to make the new one?
We can do it, but it probably will not fit properly. New materials have different characteristics than old materials. The old material has had years of stretching and weathering, and supporting frames also take a set, become loose, etc.  The surest way to get a proper fit with your new canvas is to make a new pattern using the actual boat. The exception to this might be hatch covers, sail covers, or other items that are non-tensioned.

Can you make me a new top using the old side panels?
The best way to get a proper fit for a custom canvas soft enclosure is to build from the top down, not the sides up. It is better to keep the old top repaired until the top and sides can be done at the same time. 

How do I make the right choice for my new vinyl windows?
Typically, vinyl windows are available in thicknesses from .020 to .040, and in both roll and polished sheet forms. The general principle is that the thicker materials are more optically true and last longer, but cost more and are stiffer and harder to roll up. Polycarbonate windows are nice, but not for roll-up applications.

Basically, if you want good-to-excellent optical clarity, scratch resistance, and roll-up durability for many seasons, you want good quality .030-.040 gauge pressed & polished sheet vinyl. This material is a bit stiff but will still roll up. The best quality vinyl available is a patented brand called Strataglass, available in several grades and prices. It's expensive, but once you've tried this material, you will never go back. Make sure you know what's being quoted on your window job!!

  

Is stainless steel really "stainless"?
Actually, no. There are two main types of stainless steel commonly used in marine applications; 304 and 316. Both resist most oxidizing acids and can withstand all ordinary rusting. However, they both will tarnish! 

Materials experts say that Type 304, or one of its modifications, is the material specified more than 50% of the time whenever a stainless steel is used. It has slightly higher strength and wear resistance than type 316, and is used for components where both strength and corrosion resistance are needed.

Type 316 has molybdenum added to increase corrosion resistance, but it is still not resistant to warm sea water. In many marine environments 316 does exhibit surface corrosion, usually visible as brown staining. This is particularly associated with crevices and rough surface finish.

To care for stainless tubing & fittings, rinse with fresh water when possible, especially in cracks & crevices. Don't use harsh chemicals or abrasives on it, and clean when needed with your favorite marine metal polish.