Based on my M17 (a 1976) the ballast is thousands of surprisingly tiny steel discs (punchings) roughly 1/8" diameter and 1/32" thick. These appear to have been mixed into a slurry with polyester resin and poured into the cavity between the stub keel (which appears to be part of the hull mold) and the centerboard trunk (which appears to have been bonded on after the hull was popped from the mold). As a result, it appears the punchings are more or less evenly distributed throughout the stub keel, including the area around the centerboard stop pin. The dark material you saw probably is oxidized punchings. Y our photos clearly show a breach in the seam where the centerboard trunk is bonded to the hull, so some of that is to be expected. The concern is that the steel will expand as it oxidizes causing the stub keel or the centerboard trunk to bulge. In extreme cases, bulging of the centerboard trunk can interfere with raising and lowering the centerboard. If I was in your shoes, I would go with a version of option 1. Remove the centerboard and inspect very carefully for any bulging inside the centerboard trunk. If there is none, get things as dry as possible, seal everything back up (paying special attention to the seam where the centerboard trunk is bonded to the bottom of the stub keel) and sail on. I don't think option 2 will work very well because there isn't really any void; the cavity is filled with the punchings/resin slurry. If eventually you decide to replace the punchings I don't think waiting will make the job any harder. ----- Original Message ----- From: "John Schinnerer" <john@eco-living.net> To: "For and about Montgomery Sailboats" <montgomery_boats@mailman.xmission.com> Sent: Tuesday, October 11, 2016 3:27:28 PM Subject: Re: M_Boats: Help with M17 centerboard stop pin and leak OK, bad news and good news (or at least I'm taking some as good news)... End of yesterday, per Bob's suggestion, I drilled a 5/16" hole at 45 deg. upward angle on each side of the keel, 3" forward of the stop pin and 2" up from bottom of keel. Bad news - water came out. A brief splurt (a couple tablespoons maybe) as the drill breached the ballast void. Then small stream tapering off to steady drips. Good news - or so I'll call it - the water was mostly very clear, not a load of rust and scunge. And it was entirely fresh (non-salty). I cranked up the front of the trailer some more after drilling, so the bottom of the keel is tilted slightly to the rear. The dripping tapered off to almost nothing some time in the evening or overnight. Total water in the bucket so far (all the dripping I've caught, from pin hole and these holes) is maybe 2/3 of a quart. Looking at it this AM, there may have been a slight amount of rusty water in the last bit of dripping, as there are faint traces of rusty color on the drip streaks. The water in the bucket is relatively clear, but there is some trace of both rustiness and a darker metallic coloring and some darker metallic grit (but I don't see any rusty grit so far). The water has the same metallic oil smell as the shavings from drilling out the pin hole. I've worked in shops doing machining - it is the smell of machined metal & machine oils, makes sense it comes from the steel punchings. So, now what? Obviously I need to re-do the pin hole to seal up that leak. And, I've had water in my steel-ballast keel. Not a lot it seems. Fresh. Probably only recently, at least since I've had her. Before that she sat for at least four years I think, or three anyhow. No apparent external swelling of the keel, and no binding of the CB in the trunk. How long might it take for damage to start happening in this situation? Months? Years? Decades? So I'm looking for strategies to deal with this. Any ideas welcome. Some that come to mind: 1) Drain as best possible, seal up, sail on, don't fix what isn't broken (yet). Watch carefully for signs of keel and/or CB trunk swelling and then deal with that if/when it happens. 2) Same as above, but also fill keel void with some liquid that displaces any remaining water and keeps oxygen from the steel, blocks or significantly inhibits rusting. 3) bite the (steel) bullet ASAP, open up the keel, replace steel with lead before eventual hidden damage makes repair more difficult and/or complicated and/or impossible. 4) ....??? thanks, John S. On 10/10/2016 02:37 PM, Bob Eeg wrote:
John
Take a 5/16 drill and drill 4 holes each side, front to back, at a 45 degree UP angle about 1.5 inches up from the bottom of the keel. That's 8 holes. If you have issues, water will dribble out.
If you're good, then it's easy to plug the holes with some thickened epoxy.
Bob
Sent from my iPad
On Oct 10, 2016, at 1:27 PM, John Schinnerer <john@eco-living.net> wrote:
Thanks, good idea...I think I pretty much have to make at least one or two "inspection" holes on that side of the keel to see what is going on in there and whether other intervention is needed.
Luckily this is a dry climate, low humidity place (except when it's actually raining) so drying anything out is easier than humid climates.
cheers, John S.
On 10/10/2016 01:13 PM, Wilson Frye wrote: Some heat to accelerate the drying, applied intermittently by hot air gun over a few days might dry the "hole" out. I'd try to get everything dry before sealing things up to prevent a recurrence due to expansion and contraction of captured water.
Good luck, Will
Sent from my iPhone
On Oct 10, 2016, at 3:03 PM, John Schinnerer <john@eco-living.net> wrote:
Thanks Tom,
No issues with my pivot pin or anywhere else but the one side of the stop pin. Everything else clean & dry...the CB trunk/hull joint is not visible anywhere in my photos, they are all macro closeups of the CB stop pin area...not sure what you are seeing re your comment on redoing that joint.
Anyhow... I have got the pin out, the slight bump/crack in bottom paint in the one pic was where the head of it was faired into the keel. It's a a 3/8" SS hex head bolt, head on stbd side, threaded end cut to length on port side.
There was small amounts of some non-fiberglass putty-like material of some kind around part of the bolt head, and, part of the other end (threaded end).
There was small bits of some white fibrous material as I cleaned up the leaking port side pin hole. I think it is some of the glass fiber from the keel layup, saturated with water.
The drips accelerated after getting pin out and cleaning up the hole on that side with a 3/8" drill. Overnight at 20-25 sec/drip, got a cup or so of water in the bucket. Just cleaned it out some more, drips now 5-10 sec.. Catching it to see how much comes out.
Took a surform tool to the ridge that looks like a "U" around back end of CB slot, it's just some unevenness in the keel material there. And looks like some kind of other resin/putty material might have been applied around the inside edge of the rear of the slot.
The leak appears to originate in the bore (wall) of the port side pin hole. Dry it all out with a rag and the moisture emerges first from somewhere in the bore, collects at bottom of bore, then runs to inside of bore and down trunk slot and out. I'm guessing a tiny delamination (or several) in the keel layers there, that leads to some void(s) where some water can infiltrate. Given all this, just forcing some epoxy in the existing 3/8" hole doesn't seem a certain enough fix.
I am thinking to enlarge the hole, then fill completely, and then redrill the 3/8" pin hole. As much of a fresh start as possible where the leak seems to be and the pin actually bears on the keel. Fill would be silica-thickened epoxy. Not sure if I would need to add milled fiber also; seems like overkill for such a small fill.
The pin is not badly beat up, but does have a tiny bit of a bend to it. I plan to replace it with one long enough that the cut end is smooth (unthreaded).
I will definitely add the damper of reinforced rubber hose when I put this all back together.
Any other thoughts/comments from anyone appreciated...
cheers, John S.
On 10/09/2016 03:44 PM, Thomas Buzzi wrote: How do you get your pictures to show up on this website right next to your text?????????????? I took the stop pin out and looked down the bore with a flashlight. Did the same with the pivot pin at the forward end of the cast iron keel. Found an imperfection in the glass up front so plugged one end of the hole, mixed a batch of peanut butter epoxy, loaded it into a caulking tube and squeezed it in under pressure from the caulking gun. With the other end plugged the epoxy had no place to go but into the imperfection in the bore. While it was semi- kicking I pushed a wooden dowel through the epoxy to clean out the bore. Once the epoxy was done kicking I bored out the hole to reinstall the pivot bolt. That stopped the rust colored stain from dribbling down the keel. You probably have to redo the joint where the cb trunk attaches to the hull. It looks pretty rough in your photos. Best way to do that is to (gulp!) drop the board so you can get at the seam all the way along both sides and the ends. Short of that you can remove the stop pin, check the hole, jam a wooden plug up into the cb trunk hole where your board lives and force some epoxy into each side as I explained above. Clean out the excess before it kicks and reinstall the pin. While I was reinstalling the pin which was a 3/8 diameter ss bolt I bought a piece of fuel line or reinforced rubber tubing with a 3/8 inch inside diameter. You'll need only about an inch and an eighth of it to slip onto your stop pin so that next time your board lands on the stop pin it will land on the rubber bumper you just put on the pin instead. It makes a HUGH difference on the impact of the board on the pin. If your boat had a board slam a stop pin out the bottom of your keel somebody probably fixed it by glassing a piece of metal down there on both sides to try to reinforce the fiberglass. When my buddy took the side of his keel off there were some steel punchings down there which are probably the source of your rusty water. Sorry about that. Doesn't sound like the condition of your keel is that bad though. Just jump on repairing it now to head the mess off at the pass.... Good luck, Tom B
On Sun, Oct 9, 2016 at 5:16 PM, John Schinnerer <john@eco-living.net> wrote:
Hi all,
After last trip to Waldo lake, boat sitting on trailer in driveway for some days, I noticed a small damp spot under the aft end of the keel (didn't notice it right away because it was raining off and on and there were drips various places from water running down the hull).
A bit of a rust color to the stain, but also some dark metallic color. First I thought it was from a trailer beam drain hole in that vicinity.
On closer inspection, a very very slow slow drip of water was coming from just aft of the back edge of the CB slot. Timed it today and it is about one drip every 3 minutes.
Some pictures attached...
Crawling under & feeling around and looking with flashlight etc. revealed that the moisture is coming from the port side of the slot, around where the CB stop pin is. There is some dirty-metal looking gritty material there that comes off on my finger when I rub it, like corroding metal surface. Also a bit of rusty color.
The water runs down from around where the pin enters port side of CB slot and then back along the edge of the slot and past the aft end of the slot an inch or so before forming a drop.
The starboard side of the inside of the trunk where the pin goes through is dry.
There are some surface cracks/fissures (visible in some pics) but I think they are just that - crazing of paint or gelcoat, minor scrapes from light grounding, etc.. Water does not appear to come from those; when I wipe it all dry, it just runs down from the pin/keel interface area on port side.
It almost looks like there is a metal "U" shape embedded at the rear of the CB slot - face/thin edge of U down towards ground, bottom of U towards stern, as if to reinforce where the pin goes...?
I read what I could find on the MSOG regular and photo sites about CB repair jobs and related. Only a few references to the stop pin. Sounds like the stop pin - what it is (bolt, screw, rod, etc.) and how it's installed - varies from boat to boat somewhat. This is #38, 1974. There are no exposed pin ends. There is a very slight bulge where the pin would go through, on the starboard side. The port side is all smooth, no visible pin end location.
Conclusions so far: Water coming out of there likely had to go in there. Presumably a tiny fissure or hairline crack or corroded piece of something to do with the stop pin (or combo of those) allowing water to seep slowly, slowly in that part of the keel when boat is in water. Then it seeps slowly, slowly out when it's on the hard. Don't recall seeing this after four weeks in Howard Prairie Lake in July. Don't recall if it was happening after 3 1/2 days in Fern Ridge lake (three weeks ago)...maybe, maybe not... So it may have just started.
Any thoughts? Anyone had a similar situation? Had to work on something like this?
I'm thinking at the least I'm going to have to do a little exploratory grinding for the pin end(s), figure out how it went in, how to get it out, and then explore that port side of the hole to find whatever the leak is and fix it.
I am keeping all my digits crossed that whatever cavity is around or adjacent to that pin end does not connect to the part of the keel where the steel punching ballast is. Any info on that (for better or worse) appreciated also.
thanks, John S.
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com
-- John Schinnerer - M.A., Whole Systems Design -------------------------------------------- - Eco-Living - Whole Systems Design Services People - Place - Learning - Integration john@eco-living.net - 510.982.1334 http://eco-living.net http://sociocracyconsulting.com