Ahmet;
As I said before, I replaced the original steel backing plates (if I recall, they were more like steel fender washers) on my 25 when she was a bit over 20 years old. I had some square backing plates made out of 3/16” or ¼” stainless. About 3 or 4 inches square and with the proper sized holes drilled in the middle. A local machine shop could probably knock out the 5 or 6 plates you will need in not much more than an hour – or you might get a friend with a suitable shop in his garage to do it for the price of a 12 pack. I think I put a bead of 4200 under each plate when I torqued them down, but I suspect that was actually overkill. Were I to do the same job today, I would go to Fastenall, or another industrial hardware supplier, and buy a stack of stainless fender washers of the appropriate sizes and just put two washers under each nut and retorque the nuts. Proper torque on the nut is very important. I think I borrowed or rented a torque wrench and a torque multiplier from a local NAPA store when I did my project. The photo album has a listing of the proper torque values. If you had no leakage when you removed the nut, the sealant between the top of the keel and the keel stub is still doing its job after 40-some years. Proper torque on the keel boats will keep it so. Sealant on the inside of the joint is probably not going to keep any leakage out. But sealant between the washers and the bolt in the presence of water in the bilge is a potential recipe for crevice corrosion that will weaken the bolt. If your boat is like mine, that may not be a concern. Belle is a very dry boat. Every 6 months or so I clean out the bilge – usually with a sponge. I don’t recall having accumulated more than an inch of water in the bilge since I refinished and rebidded the handrails and added some butyl around the chain plates a decade or more ago. I would personally be a bit leery of using the G10 as a backing material. You have a lot of compression under the nuts, but you also might have shock loading if you ever run aground, and a fair bit of torsional loading as the boat heels and moves in the waves while sailing. I think stainless would be a stronger and more conservative choice. Rick Brass Imzadi C&C 38 mk 2 la Belle Aurore C&C 25 mk1 Washington, NC From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Ahmet via CnC-List Sent: Tuesday, November 24, 2015 2:10 AM To: cnc-list@cnc-list.com Cc: Ahmet <ah...@sailnomad.com> Subject: Stus-List Update: Re: Keel attachment issues on a C&C 25 A few weeks ago I started a thread about the rust on my keel bolt washers <http://www.boatjuggler.com/images/pic2.jpg> . Today, I bit the bullet and removed one keelbolt with the boat in the water with a 3 ft breaker bar extended with a pipe. The nut seemed to still have the right torque, and came out once I applied the force in the right direction :) I was able to peel off the corroded washer/backing plate with a screwdriver and a hammer. The bolt threads were clean (pic 5) <http://www.boatjuggler.com/images/pic5.jpg> . So was the nut l (pic 9) <http://www.boatjuggler.com/images/pic9.jpg> . It was all stainless steel. I did not get a chance to test the magnetism. I will do tomorrow. At no point was a hint of water seepage. Whatever was left as the rusted plate under the washer is in this picture <http://www.boatjuggler.com/images/pic13.jpg> . It looks like an iron backing plate <http://www.boatjuggler.com/images/pic14.jpg> . It is very magnetic. All I had was galvanized washers. So I put the good stainless steel washer to the bottom added 2 galvanized washers and a galvanized lock washer and tightened the nut back to approx, 200 lbs-ft <http://www.boatjuggler.com/images/pic11.jpg> . Probably useless, but I put some boat-life under the stainless washer which probably got totally squeezed out. In the picture <http://www.boatjuggler.com/images/pic12.jpg> you can not see the stainless washer because it is thinner and hidden behind the silicon. There is a slight bulge at the base of the keel bolt. Repair plan: I am planning to use: * Marine-Tex just to flatten out the bilge area, probably max 1/4 inches in the deepest areas, * use a layer of 3m 4200 * a 4 by 4 by 1 inch G-10 board as a backing plate * followed with triple 316 stainless washers. Does it look like overkill ? Should I just use 1/2 inch thick G-10 boards ? I will keep an eye on the galvanized washers. I am not very comfortable mixing galvanized with stainless. Now that I have sort of an idea what is under the nuts, I will complete the job for the other washers when I pull the rest of the nuts out while on the dry next spring. If someone sees something wrong in all these (besides removing the nut while in the water, which seems to be a very contested subject ) please feel free to scold me :) Thank You Ahmet Winthrop Yacht Club / Constitution Marina, Boston, MA 1990 Irwin 43 CC "Waterdancer" 1973 C&C 25 "Tabasco"
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