In a message dated 4/8/02 8:04:04 AM, stevemc35@attbi.com writes: << Has anyone had a good look at their centerbord slot or knows how it's constructed? Maybe this is a question for Bob or Jerry: My question regards the joint just inside the lip of the centerboard slot, where the inside wall of the trunk meets the outer hull: of what does this joint consist? Does it ever require any maintenance? On my 1981 M15, there appears to be a joint consisting of some kind of resilient caulk, rather than fiberglass or epoxy, which is what I suppose I expected? Is this normal? I haven't found anything in the archives that refers specifically to this joint, but if it is not fiberglassed then should it not require maintenance from time to time? I admit I have no evidence of trouble there -- unless the existence of caulk there is itself evidence of a previous repair. But as long as I have the boat up on stands, and the centerboard out, it seems like a good time to make sure everthing down there is hunky-dory. -- Steve McClellan 1981 M15 #152 >> Hi Steve, I spent the last hour on Keith's web page looking at the *old* archives (pre 2001), and finally found my old post from 1999 regarding this condition. I am including it below. If your opening is similar to that of my description below, you might want to undertake the process I describe. Given that the products I mention were purchased in 1998, you might want to check with Interlux to see if anything has changed or been renamed. One thing that may not be clear from this early post (I sent some follow-up posts) is that my primary reason for taking on this work was to prevent water incursion at the exposed laminate edges of the hull opening. I was not having any problem with the centerboard or trunk. Let me know if you have any further questions. Scott Grometer M15 #478, "bebe" Original posting, 1999: From: Wilsometer@aol.com Subject: Re: M_Boats: Center Board Trunk Date: 17 May 1999 03:59:28 EDT In a message dated 5/17/99 4:40:36 AM, you wrote: <<While laying under my M-15 today (note - the boat is in the driveway on the trailer) I noticed there is a gap between the centerboard trunk liner and the outer shell of the fixed part of the keel. Some sections around this perimeter appear to have a filler sealing the joint. I assume the joint should be completely filled in. Has anyone else noticed this condition on thier boat? Is resealing with epoxy a dirveway type of repair or a "haul out'? It looks like I could get to most of it with a putty knife, but wonder how long it would last without being properly prepared. Is this serious problem and should I repair it before Dream Catcher goes in the water this year? Any help will be much appreciated. Don Haas, M15-248>> Don, Virtually all M15's I looked at had this condition to some degree--some a lot worse than others. One M15 I looked at had started to delaminate at the hull opening. In addition to delamination, This same boat also had so many bottom blisters as to make me wonder whether the boat was salvageable. My boat, on the other hand, was essentially brand new (in the water maybe one or two times for demo sails before being shrink-wrapped for storage). In spite of this, the centerboard opening was irregular in shape and had fiberglass "hairs" extending from the rough exposed laminate. The boat did not leak, so I guess it had filler where needed, but I was uneasy about the whole situation. I decided to get a second opinion from a friend who is a marine surveyor. He was not comfortable with the exposed fiberglass laminate, and was especially disturbed by the exposed fiberglass "hairs", which, he suggested, would have the effect of wicking water into the laminate. He suggested that If I merely daysailed the boat occasionally, and trailered it some distance so that the laminate might dry, that I might not have any problem. When I told him of my plans to leave the boat in the water for three or so weeks at a time while cruising, he said I had little choice but to repair the joint and close the bare laminate. I decided to undertake the work myself. I asked the surveyor for his recommendation, and then got specific product information from Interlux before proceeding. What sounded like a simple process ended up being a messy and time consuming affair. Still, I am glad I did it myself. I suspect that no yard would have taken the same care, or if they did, it would have cost a fortune. I decided to go ahead and do a full barrier coat on the keel while I was at it. It was my original intention to do a full barrier coat on the entire bottom (to the waterline), but I decided to see how the keel came out first. In retrospect, I would have liked to have pulled and barrier coated the centerboard as well as the entire inside of the trunk. As it was, however, it took nearly a week to sand, fill, fair, and get seven barrier coats on the keel and opening. The finished product was worth the work. The opening in the hull is now perfectly shaped and flush to that of the centerboard liner, and I have no concern that the hull will ever delaminate at this junction. While not exhaustive, I will outline the general steps taken below: 1) I jacked up the boat while still on the trailer by placing a floor jack under the ballasted section of the keel. By alternating fore and aft, I was able to slip the old bias-ply trailer tires (the only good use for them in my opinion--I switched to radials) between the hull and trailer bunk boards until the boat was fully supported some 6" higher than the normal trailering height. 2) I masked the hull leaving the keel exposed (Use 3m blue "long mask"). 3) I solvent washed (Interlux #202 Fiberglass Solvent Wash) the entire keel surface, the hull/trunk joint, and as far up the centerboard trunk as I could reach. I used a brush to get the solvent into the crack between hull and trunk. 4) I sanded all areas with 80 grit, and where necessary, ground down the opening in hull to better correspond with the more uniform trunk liner. I also was careful to cut all exposed fiberglass hairs. 5) Vacuumed all fiberglass dust from joint, and repeated solvent wash as in #3 above. 6) Applied Interlux 1000/1001 to all exposed laminate at hull opening and bottom of centerboard trunk liner. 7) Filled void between trunk liner and hull opening with Interlux/VC 'Watertite'--a two-part epoxy filler designed for blister and osmosis repair. 8) After Watertite cured, sanded opening smooth and fair so that hull and trunk appear to be continuous. 9) Repeated solvent wash of all sanded/filled areas. 10) Applied seven coats Interlux 2000/2001 Barrier Coat System making sure to apply each coat within the previous coat's open time (limited time window between coats without having to sand). 11) Spent hours cutting four days worth of epoxy drips out of my hair (and I had even worn a hat!) My intent was to wet sand the last 2000/2001 coat and finish with two coats Interlux/VC 'Underwater Epoxy' (a hard, super slick white finish with teflon that is easy to wet sand or burnish smooth). It got down to the wire, and I had to choose between having a race smooth bottom or cruising in BC. The latter won out. I called Interlux, and they indicated that there was no penalty in waiting to apply the Underwater Epoxy at a later date. They did say, however, that I would have to resand the 2000/2001 surface to get a good mechanical bond, and that I might want to add a couple of coats prior to a final wet sanding and application the Underwater Epoxy. I know this sounds like a lot of work, but if you had seen the same blistered and delaminating M15 that I did, you might choose the same course of action. By the way, it is extremely important that the boat be thoroughly dried out before undertaking any of the above work. The last thing you want to do is seal in any moisture that has not been able to work its way out of the laminate. My boat sat indoors in a heated garage for almost a year prior to my starting this process. This was probably a bit longer than necessary, but I was too busy to take it out anyway. Let me know if you have any additional questions. Scott Grometer, M15 #478 "bebe"