I know that glassing a keel promotes rot, however, I was thinking of about 4-5 layers of 2 1/4" wide, strips of 6 oz cloth running the length of the bottom of the keel (Vacationer) to protect it from rocks, beaching etc.
The rest of the keel would have no glass, just paint.
Any thoughts on this?
Just screw a length of hardwood to the bottom of the keel (bedded) and call it a day. The hardwood shoe will get beat up and in a few years you just yank it off and put on another one. Metal (aluminum, bronze, steel) are also common shoes for keels, as is plastic, like HDPE.
Thanks Paul, IÂ have a surplus of glass cloth and epoxy but no hardwood so if I use glass strips as a protector would that be a bad thing?
'Glass strips, if bonded conventionally, will tend to trap moisture attempting to drain out of the keel, which isn't good. If the 'glass strips where made on a table (several layers of fabric rolled out on flat bench) it could be allowed to fully cure, then cut to shape as required. This would be similar to using a separate keel shoe and would be mounted the same way, with screws over bedding. 'Glass fabric, by itself isn't very strong, unless it's quite thick. It also isn't as abrasion resistant as other materials. You'd need a minimum of 1/8" thick to be anywhere close to effective against a rock. This is approximately 6 or 7 layers of 10 ounce cloth (assuming .017" per 10 ounce layer), depending on resin/fiber ratios. Of course heavier fabrics will bulk up with fewer layers.
Simply put, a layer or two of a light weight fabric (10 ounce or less) just isn't going to offer much protection.
Thanks again Paul. I will follow your advice and use a strip of oak. What would you recommend that I use for bedding?
3M-101 if the boat will be in for long periods, 3M-4000 if you don't plan on dunking her for more then a couple of days. Red oak is useable if that's all you can get, but it doesn't like getting wet and rots pretty quickly. I'm more of an inert materials guy on keel shoes. Metals are good and a length of plate aluminum, cut to the keel's width will work fine. Stainless works, but will cost more and is hard to machine. Most big box stores sell 8' lengths of flat bar stock in various widths, but a trip to the local welder's shop will get a better price and you can get better material, such as 6061 T-6 aluminum, which will last a lot longer then the 5000 series junk they sell at Lowe's/Depot. Lastly wet out the screw holes with epoxy, so water can't find a way into your keel through these holes. This is the most common point of ingress for moisture in a keel.
I'm going shopping for metal this Friday. Tomorrow is a good epoxy day here in Ontario and I'm on my third coat for the hull. Thanks for all the help Paul.
Herschel:Â How about some photos?
Dave
I'll try to send some photos when I go into town next week. We retired to the country, 100 acres next to Algonquin Park, a wilderness area in Ontario. The dialup internet will not do photos and no high speed internet is available, no cell phone service, just lots of trees.
Tim Hortons, a Canadian coffee shop has wireless internet so I'll bring my laptop and try there. By the way, my Weekender is on the Stevenson site, page 13 or 14.
We spend our winters in N.C. and we've got a place with all the luxuries like high speed.
I have a funny story about my aluminum keel protector. I used to fly a DeHavilland "Otter" seaplane for a living, around the time I was building my boat. She was upside-down for bottom paint and I still hadn't decided what to use for a "shoe" on the bottom of the keel. One day my boss was flying the plane, and tried to beach it on a shore that was a little rockier than he was expecting, and when he came back to the airport I saw that he had knocked about half the starboard float's keel "wear strip" off, and the other half was dangling from the bottom of the hull. Half an Otter "wear strip" is about the right length to be a whole weekender "wear strip", so I pulled it off the plane and screwed it to the bottom of my boat. It's still doing its job, at five knots instead of sixty-five knots, ten years later. I have the most expensive keel protector on any Weekender ever.