Starboard
I would suggest using Starboard or similar HDPE product as the backing plate. You can buy the stuff at most marine or home supply houses. You get the advantages of strength and invulnerability to water but it works like wood. Drilling aluminum is doable but can be a pain and is unnecessary for your purpose. Use a cleat that's oversized and cut the backing plate do that each dimension is at least half again the footprint of the screws holding the cleat to the boat. If you can do twice the footprint, even better. For installation, drill the holes twice as large as necessary. Then tape the bottom and fill the holes with thickened epoxy. Redrill in the correct sizes and you'll have a nice plug protecting the deck around each screw. Countersink the holes at the deck. If you're unfamiliar, this means bevel the tops out to make a slightly conical shape for the first 1/4 inch of depth. Don't make the cone all the way through. Use 3m 4200 or similar to prevent leaks. On my boat, I'd use 5200 but some are afraid it makes things too difficult to remove. I my theory, you can't make a mooring cleat too difficult to remove. As to the mooring itself - it'd go for dual pennants. The shorter one would be a minimum of three times the freeboard at the mooring chocks. A bit longer is even better. Make the longer one a few feet longer. This way they don't wear at the same rate and if one saws through the next is still fresh. Line diameter is a question of comfort. Lines have become so strong the minimum safe working load line will be narrow. I use 5/8" line on my 25 because its easier to handle. That way when its blowing I can hold the line well enought to pull the boat forward for securing. I like to splice my own pennants. The first splices I ever did were for my first set of pennants. I use three strand - its cheaper and nice and strechy, a good characteristing in a mooring line. Justin - O'day Owners' Web
