Rebalancing the keel of a CD31

[jparmen]

This weekend I spoke to Gordon Reed (of Robinhood-Derektor) at the Maine Boatbuilders Show. He asked me if I had re-balanced my keel yet. Apparently this involves putting 600 lbs of lead shot down in the (cleaned out) bilge and pouring in enough epoxy to cover it all and make a new "bottom". In addition to improving the balance and handling of the boat this also provides a shallower, easier to clean bilge while still leaving ample room for the bilge pump and oil absorber. It shouldn't interfere with the drain into the keel. But wouldn't this make it even more difficult (if not impossible) to get to the holding tank compartment ...if one ever had to?

Has anyone done this? I''ve had this boat for 18 years and this is the first time I've heard about it. Maybe I don't read this board often enough!

Best,

Jim

[Jim Walsh]

Sounds pretty wacky to me. If it was intended to correct a problem it might make sense. If your boat isn't exhibiting a "bow down" attitude what could be the reason for adding weight aft. If your boat is "tender" it might make sense. Seems like an expensive solution to a non-existent problem.
I find it incomprehensible that hull 27 is the only CD31 which sits on her lines and stands up to a full press of sail.

[Sea Hunt Video]

Jim P.:

I'm a rooky and know very little about keels (except that when they point down it's good; when they point up it's very bad) but I would want to get a second and third opinion before agreeing to something that sounds pretty drastic.

For example, you may want to speak with Dave Perry ("Mr. Cape Dory") to get his thoughts on this issue. I tbink Dave is retired from the old Robinhood Marina but someone should have contact information for him. My limited dealings with Dave were always VERY pleasant. He's a decent, honest man.

I remember years ago I took an old truck to a dealer for some simple work but required a lift. A couple hours later I got a call from the mechanic telling me that the transmission was almost shot and I needed to replace/rebuild. After learning the mechanics worked on commissions I declined the invitation to hand over $2,000 plus and drove that truck for 5 more years with not a single tranny issue.

Like Jim W., I am suspicious. But then, I am a suspicious person by nature and training. "Just because I'm paranoid doesn't mean someone isn't out to get me" is one of my favorite mottos. I think someone may be trying to pad their commission book with your wallet.

I asked my friend "Mr. Google". Not surprisingly he had not heard of any procedure similar to what you described Mr. Reed wanted to do. Of course, this may all be legitimate and we will all learn something new and exciting.

Please keep us posted on developments.

[Frenchy]

I second all those thoughts. The ballast/displacement ratio of the 31 (.378) compares well to other CDs
(.375 for the 36,.353 for the 30 and .388 for the 28) and there's no trim problems reported.
Roberto, your truck repair story is similar to when my wife brought her car in one time and was told "Lady, please don't
drive this car home : The ball joints are completely shot and your wheels could fall off any minute" She called
me sobbing on the phone and I told her to drive home anyway and that I would look at it. The ball joints were fine.
Another leech looking for a host. -Jean

[John Stone]

I’ll get on rebalancing the keel right after I pick up some batteries for the sound powered phones.

[Steve Laume]

I once bought a Typhoon that had a couple of hundred pounds of lead ingots in the bow to counter balance the 6HP engine the guy had hanging off of the transom. It did a very nice job of raising the waterline to the top of the boot stripe. A big engine and extra ballast makes for a slow Ty. More weight is not usually a good thing, if you can avoid it.

Please do not put off replacing all the winter air in your car tires with fresh summer air, Steve.

[sachemgfp]

We had a Cape Dory 31 Hull # 29 from 85 thru 98. In 89 we took the boat to Robinhood Marine, for the Cape Dory Rendezvous, a had 300 lbs of lead installed in the bilge area. As stated the bilge was smaller and SHE pointed much better. This was the reason explained to us by the factory back in the old days for adding the extra ballast.

Regards,
George
S/V SACHEM Crealock 37

[John Stone]

I added 230 lbs of lead pigs to the bilge of the Far Reach under where the engine had been located. But I was compensating for removing a 500 lb 4-107. I also store 140 lbs of spare achors there plus another 100 lbs of additional chain. So I “rebalanced” my boats center of gravity for a specific reason.

It’s one thing to add some weight to port or starboard to compensate for listing due to an imbalance in galley icebox layout. It’s a whole other thing to add so much weight to correct fore and aft trim that was not owner induced.

According to my calculations, adding 600 lbs of lead on CD 31 amounts to a 15 percent increase in ballast and moves the B/D ratio from 37.8 percent to more than 41.25 percent. That’s not a small thing. My sense is there is not much unknown about the entire Cape Dory line. So it’s surprising to me that a Robinhood employee would make such a comment that would come as a surprise to the forum. Jim Walsh seems to know an awful lot about the 31. If he is surprised then I would be very suspect about such a statement that the boat needs 600 pounds of ballast added.

I agree with Roberto. Dave Perry would know if there is rational for such a statement.

[Sea Hunt Video]

Jim P.:

I would be interested to know what precipitated the statement from Mr. Reed to "rebalance the keel". Did you say something to him about the performance or pointing characteristics of your CD 31 and he responded with "rebalance the keel"

Or did Mr. Reed bring up the issue "out of nowhere"

Inquiring minds want to know.

[jparmen]

Wow...you guys are right on top of this!

First...Gordon brought up the point...not me.

Next...I've spoken with him before about other topics...and I think he's honest and sincere. I wouldn't at all compare him to a rip-off artist in a car repair shop.

And...I will call Dave again. He's retired now, living in Portland, but available for discussions. I spoke to him two months ago about the history of my Cape Dory 24 trawler....(which really is another story altogether, but a fun one for this forum if anyone is interested. Bothe he and Gordon refer to it as the "Tippy Trawler" because it, too, has (had) some ballast issues).

IOLANTHE is hull 24....out of (I think 63...is that right, Jim?). This means she was one of the earlier ones. I believe Gordon said that the problem was recognized during the construction period and corrected in some of the later boats. George had hull 29, so he was probably in the same category I'm in. If I'm correct, then some of the boats numbered (let's guess) from 50 onward might have small bilges. If so, we could ask someone who has one of those late-numbered boats.

George...can you remember if someone suggested the modification to you, or did you find pointing to be a problem when you took it in to Robinhood?

Thanks for the comments. I can take all of these ideas to Dave and see what he says.

jp

[John Stone]

So some interesting questions might be were the boats not ballasted to Carl Alberg’s specification or was there a design issue or some other factor at play? Or is this just an opinion based on the fact the CDs tend to have less initial form stability than more modern designs? I for one would be interested to have some insights.

[moctrams]

I wonder if anyone notices any difference when a heavy engine line the Volvo MD-7A is replace with a lighter Beta engine. I replaced my old Volvo MD7A weighing 385 lbs. with a Beta MD722 weighing 233 lbs. That is a difference of 152 lbs. I did not notice any difference in the way the boat performed. I did notice she did not sit so low in the stern.

[Jim Walsh]

Hull form (and a good set of sails) dictates pointing ability. A deep bilge is a godsend, just ask the guys with the shallow bilges who find water in all the wrong places. I'll not be "rebalancing" in the foreseeable future.

[sachemgfp]

In regards to who offered the comments about adding more lead in the bilge. At the time Cape Dory was still building boats in Taunton Mass. The factory had a very active quarterly newsletter and I frequently chatted with Howie Meams (remember this is 1989). I met Howie in January 89 at the New York Boat show and he mentioned that the 31 had a problem that could be corrected by adding additional lead in the bilge. To me, this was not something to be done at the local marina or body shop, so when the August gathering was being held in Maine at Robinhood I made arrangements to sail to Maine participate n festivities and leave the boat with them. Here I met Gordon Reed and developed a very good relationship with him while we owned the 31. We sailed back to CT. that late August.

My comment on better pointing is my sailing ability with the boat, same sails the next season.

All I can say is my experience with the additional weight had no negative effects, we sold the boat in 98.

George
S/V SACHEM

[jen1722terry]

Interesting thread.

Jenn and I spent quite a bit of time at Robbinhood the last two years arranging for and getting a new engine and a few other mods. I recall a conversation with Dave Perry, who was still working at Robbinhood, where he mentioned that some 31 owners added lead to the bilge. 700 lbs. is a figure I recall. He said he wasn't sure it was necessary.

We have hull #33 and we know it was raced for about 15 years on the Chesapeake. She came with a full suit of custom racing sails, including spinnaker and a big genoa. If she was not performing well with those expensive sails, you would think the prior owner would have added some ballast.

Like Jim Walsh, we have not noticed any issues with stability or pointing. We don't race our 31, however, so our opinion may not be all that well informed. I have sailed a wide variety of chartered boats in my days as a skipper for a sailing club in Philadelphia, and I think our 31 points as well as any cutter-rigged sloop with her weight and hull type. If we put on the big racing genny that came with the boat, she would point a bit better.

As for the weight change with switching to the Beta Marine engine, we did the switch last year but sailed with it only a few weeks, so we can't yet comment on any changes in handling. We probably made up for the weight loss by adding refrigeration which allowed us to really load up the ice box.

And I agree with Jim that a shallow keel bilge can be a problem in rough seas when the boat rolls. We also think the deep keel bilge is a safety feature. We have our high bilge water alarm sensor about a 10 inches above the bottom of the bilge, which allows for about two more feet of flooding before the bilge overflows. This gives one more time to figure out where the water is coming in and to stop it.

So there was a quarterly news letter for Cape Dory back in the 1980s? Wow! I wonder if anyone still has them, as I would love to read them. Dave Perry or Andy Valvolitis would probably know. I did not notice any old newsletters in the library at Robbinhood last summer.

Nice thread. Cheers to all of you. Spring outfitting soon. I have always enjoyed boat yards in the spring with all the happy busy people exchanging advice and yarns, and anticipating a great new sailing season.

Jenn and Terry