Skip the "UV-treated" or "UV resistant" thread and go with PTFE thread that is impervious to UV deterioration. As some have mentioned
Gore's Tenara is one option, my favorite thread to use is
SolarFix PTFE from Quality Thread and Notions Co.
As someone already mentioned
Rochford Supply,
Sailrite,
Sailmaker's Supply, and
South Star Supply are good sources of the things that you will need. A few things to keep in mind when
tracking down what you are looking for:
- There are only a few sites which offer this stuff to the public so take the time to check prices on each one if you are looking for a good
price, sometimes one place will have the best
price on one thing but be the most expensive on everything else. Of course you'll have to be careful to make sure that added
shipping costs aren't eliminating your "best price" margin of ordering from the other shop.
- Don't go crazy ordering super-expensive scissors from a "marine sewing supply" shop if you aren't going to make this a career (and maybe even if you are). I have great-quality (and expensive) KAI scissors in my shop but I also have several
$5 pairs of teflon coated scissors from Home Depot that I use for 90% of the cutting that I do. The KAI's get reserved for specific material cutting needs and if I wasn't doing this as a business I would not have them.
- The Marine Sunbrella is your best bet for most of the projects that you mentioned unless you want to try some of the other products out there such as
Weathermax. The trade-off for fabrics such as Sunbrella Plus (with a
polyurethane coating on the underside) is that the fabric loses the breathability that is a huge plus of Sunbrella. Sunbrella Plus would be a good choice for a bimini (although I would go even further and use
Seamark by Haartz) because it doesn't need to be as breathable. For a
dodger or a cover such as a sailcover the build-up of
condensation, when combined with a small amount of dirt, will create the ideal growing conditions for
mold and mildew (we've all seen those gross green-stained
sails that were kept under the sail-cover that didn't breathe).
- Don't skimp on the closures/fasteners: Sometimes when you're doing your own canvas
work it seems like such a waste to buy the tool to close or attach whatever fitting you would normally have chosen, so it is tempting to choose a less-suitable fastener that is cheaper to attach. Don't do it. By skimping on the fasteners you are going to place the entire canvas
project at risk of becoming a waste of effort much sooner than you might imagine. If you don't want to buy the tool then buy the fasteners and see if your local canvas shop will put them on for you.
- Grommets - Spur grommets only, period. If the grommet might at any point be under a bit of tension spur grommets are the only thing you should use. Unfortunately spur grommets cannot be set by the same die as a rolled-rim (or regular) grommet.
The list could go on and on but that's good enough for now...