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I've seen boats where the keel does not go all the way to the bottom,
and even the encapsulation of a solid material allows for water to collect on the bottom. About two years ago, a guy next to me in the marina had a Hunter, he drilled a hole on the bottom of his keel to le the water drain out. Only he drilled a hole too small. Ii'd warn against drilling a small hole--if you drill a hole, drill one big enough to let things drain out and some air to go through. A small hole clogs up. Also, if you have a void you'll have to fill, you'll have to work on the hole, and possibly drill more holes to fill it in. So, let's assume that your center/weight is fine. It's possible a bit of the lead broke off and fell down. If you can move it with your finger then: 1) it's probably not enough weight to make a difference, and 2) your hole is probably big enough. Here's my two cents on fixing: 1) find out how big the void is. Tap with a hammer, and drill. Don't be afraid to drill--the repair will be as strong as the original material, or at least close enough to it. 2) once you've identified the void area, you probably have drilled enough holes to let it dry out. I'd say a hole every two inches is not too many holes. 3) let it dry out. A moisture meter would help; yoru local surveyor or fiberglass shop may let you borrow one; it's not worth buying (they'rd about $350 starting). Alternatively, tape small pieces of plastic on several places along the area. If when you get back, there is moisture on the inside of the plastic then the thing's not dry yet. When you're sure its dry (best leave it for the season!), proceed. 4) fill in the void. First, close off all the holes but the bottom most one. Insert some tubing on the bottom hole. Remove the tape from each of the other holes and blow through the tubing. The idea is to make sure this is one continuous void you'll be filling--if air does not flow out of one hole, then that is not part of the same void. Other drill more holes, or identify the next void. Also, buy some empty caulk tubes (I know West Systems sells some) When satisified, thicken up some epoxy with microfibers or whatever your epoxy provider sells for structural repairs. Thicken it enough that you can load up your caulk tube. Remvoe the tape, and starting from the bottom hole, fill in your void. As the epoxy reaches a higher hole, tape it over (use "preservation tape" if possible) and continue filling until you have filled the void to the topmost hole. Do not use the fast hardener for the epoxy, unless you do this in the dead of winter. You will likely leave this a day or so and come back to it, so use a medium hardener. The slow is often too slow, but if it's 100 degrees out the slow will do too. Do not worry about making the outside pretty at this point. Remember the trick here is to fill the void from the bottom up...fill it from teh top down and you'll get air pockets. 5) when all's set, tap it with a resin hammer to make sure you have no voids left. If you do, repeat the process. (the new void would be smaller.) 6) when you're satisfied, the rest is making it pretty. I'll assume there is no gelcoat here. If there is, post back or email me. Sand down the holes with the epoxy which will no doubt be pouring out at this point. If you're satisfied with the smoothness when the epoxy is flush with the rest of the keel, then proceed to step 8. If not, then sand down below the level of the rest of the keel--feel free to sand down a larger area--all this will do is provide a greater surface area for the epoxy to stick to. This is _necessary_ if you use poly/vinyl-ester resins rather than epoxy. Make sure you dewax _before_ you sand. 7) thicken up some epoxy with their "fairing filler". Thicken it pretty well so it will not run down the vertical surface. Then put it on the holes you just sanded, making sure it sticks up above the level of the keel. This stuff sands down easily, so don't hold back. In theory, you should be able to get it pretty fair with just applying it, but I've never been that lucky. Also, remember that epoxy shrinks just a bit when it kicks, so make sure you load up above the level of the keel. When thsi is kicked, sand it down until it's fair. "fair" is in the eye of the beholder, but i fyou have a small area it should be pretty easy. 8) this is icing on the cake. If you look at your faired area, you'll see that there are small holes in the epoxy. This is the way it is. You can fix this, and also provide a better water barrier by painting on unthickened epoxy or, better yet, epoxy with water barrier additive. (The latter has instructions on how much to use.) Wash down the old epoxy to remove amine blush, sand down a little bit, and just paint on with a disposable brush. It will drip, but you'll just sand that down in the end to make it fair. 9) you're done. Put on your bottom paint. As for the impact damage, the procedure is the same as above, except of course that you do not fill in the void; instead you plaster on the thickened epoxy. Make sure you sand/grind and grind again--grind enough to make sure that you have gotten rid of any bad fiberglass. The fiberglass should look smooth and homogeneous. If you see any white spots, grind further. IF the end result is less than about 6 inches, and not more than 1/2 your thickness, then a structurally-filled epoxy willwork. If not, you'll have to lay glass--which you seem to have done already. This is nicely outlined in Don Casey's book, "Sailboat Hull and Deck repair" ISBN 0070133697 amazon link: http://www.amazon.com/exec/obidos/tg...20927?v=glance I'd recommend getting this--you'll have the time to wait for shipping while the keel dries. It has very good illustrations which will do what my message failed to convey. Third to last: this may sound daunting, but it's not. If you're interested in doing your own work, can shoot a caulk gun, you should be able to do this work. The boatyard will probably charge you too much. second to last: Epoxies come in all varieties. West System is the most common, and its' a good epoxy. Due to funky ratios, West Systems is best used with measuring pumps. Some others are equally good, but do not necessarily require measuring pumps. In my experience, if the ratios are easy (e.g. 2:1), then a pump is less necessary, provided you are mixing up a quantity that would fill up at least half your measuring cup. This minimizes errors. If you are beginning with epoxy, get the pumps. And for crying out lout, wear gloves and a mask. You'll be spending enough on mixing cups and epoxies, and I bet you sand down your bottom paint every now and then. The paper masks don't do anything. get something similar to the 3m 6291: http://www.natlallergy.com/allergy_r...ion-masks.html the P95/P100 filters are good for sanding (including your bottom). For applying epoxy in open environments you won't need a vapor cartridge, but if you do any work inside then the vapor cartridges are necessary as well. The only benefit to not wearing these is less work for your embalmer. Lastly: This is, of course, my opinnion. Every job can be done three different ways, and I'm sure others in this group have equally good or better options. I hope they share them. Cheers mickey |
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