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KEEL


BJ

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I was out in the bay the other day with my vacationer. the wind build up to about 30 knots. needless to say with all the sail up and by myself it was a little dangerous. I would like to put weight on my keel and was wondering if anyone experimented with that.

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BJ a number of us have ballasted our boats to improve their performance. In this case you would have been better served by a double set of reefing points in your main sail. My ballast is lead plate mounted around the lower mast box in the foc'sl. I forget just now how much is there. Others have used bulbs cast to sandwich the keel. Seems one builder made a portion of his center keel section of lead. There are various ways to do this. You don't get enough lever arm to change the righting moment much: however, the trim changes are the real benefit. My boat sailed nose high and was hard to tack. Adding the weight tamed the tacking and eased some of the rudder pressure by changing trim. The best practice is to get a few hours under your belt to truly get the feel of what your boat wants to do; then, use sand bags to determine the placement and amount of ballest you need for your situatiuon. 30 kts is way too much for a full press of canvas on the VACs. The lead wouldn't have helped too much. It would keep the nose from being blown around though.

By the way, have you heard of the BYYB SE Fleet?

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Hey all, Craig, how did you mount your lead plates, I have been Saving a ton of lead tire weights and will melt them down and cast them into bricks for ballast, I am going to mount my battery in the forward compartment for weight but I dont think it will be enough.

BJ, I cannot answer your question, But when I get done with my vacationer I will definetly be sailing it off of Casperson Beach and Charlotte Harbour, I live in S.C. but used to live in Port Charlotte, and have family all over down there so maybe we could get together and sail, Its a little way off right now but who knows,

Speakin' of S.E. Fleet are you going to the messabout in april Craig? I think I might depends on my doctor bills but I am leaning twards it.

Brian.

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Seems like it was ~370lb cast into 1" plates that overlapped the mast box from each side. I cut a 2x4 to wedge in front of the lead to keep it in palce. Don'rt turn the boat over!! :lol: Just make a plywood box the size and shape you need. Remember you need to carry this piece so keep the number up and the weight per piece down. Ray cast bulbs for his keel and through bolted them. His seemed to work real well too. Search over at BYYB for that or maybe his web site. I don't know about the spring messabout Brian. If they don't cancel this program I will be flying every weekend for the next 3 months. Too soon to tell you know?

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Well hopefully you can, If not, I will catch up with you at some point this year.

Yeah, I like the idea, keep the number up and the weight down, ya know, I still have the template I made for the mast box supports, I could cast them in the same shape or even divide them into two pieces each layer, then do like you said sail it to see how much weight I need and where.

Thank You for Your Advice Craig

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  • 1 month later...

Hello,

I have been playing around with some planned modifications, including keel ballast.

I built a Payson/Bolger "Tiny Cat" which is a center-board catboat. I cut out a box shape in the center-board, drove nails to the inside and poured 11 lbs. of lead to get zero buoyancy.

I am not sure how I am going to get the ballast that I want but like I said, " I am playing around", with the kit design in AutoCAD and thought of cutting out a section of the Vacationer keel and pouring in some lead.

I have uploaded an image to show what I mean.

There are so many ways to achieve some ballast but I like the idea of the ballast not changing the shape of the keel.

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Rock on Ray! I agree and I am the type to go exploring the islands of Muscongus Sound and Bay, which is where I am from. I have taken a 16' center-board dory with a sail [no reef lines] and rocks for ballast from West Palm Beach and Ft. Lauderdale to Freeport, Bahamas and Bimini numerous times. That is a 40 mile stretch and never came close to capsizing.

The beauty of building your own vessel is the modifications that you can make to please yourself.

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Hey Ray,

Thanx for the link to your images. I have similar ideas for my ballast. I believe that I will probably use the keel's form and leave 2 or 3 inchs top and bottom there by distributing the ballast over a larger area. I will have more under the mast and cabin. It will be wider in the forward end and taper as it goes aft. Thanx again for your input.

Norm

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I am thinking 400 lbs+/- and tapering more towards the aft section. I have a degree in mechanical drafting and computer technology besides working with wood for 50 yeaars so I also ave a machinist's bible for figuring out the volume or space needed for the desired weight. I am attaching an ever changing image. I've heard that there're worth a thousand words. :wink:

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I am planning on making the ballast in place using the full width of the keel and covering with glass mat, cloth and resin. All surfaces on the vessel will be coated with resin, inside and out before painting to keep moisture at bay. Once the hull bottom is attached the keel will be rigid along the lead line.

The lead will be bolted or screwed into through the deck and joiners at the ballast's thickest, forward end and will have steel rods [vertical and horizontal] inserted into the lead and wooden keel for strength. I will use large lag bolts to attach. The center layer will be 3/4" plywood except where the lead will go to except the stem and stern post lamination. [lead being a full 2 1/4" thick by 8" high at forward end, 8 0r 10' long tapering to 0" and weighing 437.5 lbs @ 10' long]

Lead weighs 710 pounds/cubic foot and by using this shape and thickness I could calculate the volume and weight as a wedge [(2t+t)bh/6; where t=thickness, b=bottom length anf h=height at highest end in inches and 1 cubic foot=1728". So ((2)2.25+2.25)X8"X120"/6=864. 864/1728=.625. .625X1728=437.5lbs.].

If I used the center laminate space only, I would only get ((2).75+.75)X8"X120"/6=360cubic inches and 360/1728=.21 and .21 of 710=148 lbs. Not much help there.

I am trying to keep the lead as low as possible and to have the most weight at the focsl or under and aft of the mastbox.

The casting is the same process used on the tiny cat where I poured the lead directly into the center-board a little at a time. This small [1"X10"X10"]lead zero buoyancy mechanism was held in place with 20d commom nails driven into the inside edges of the opening prior to pouring. I poured too much lead and then used a belt sander to get a smooth surface followed by glass cloth and resin. and used 1/4" luan plywood underlayment for the boat's skin.

I used this boat for 2 seasons before selling with no ill effects or water penetration, often leaving the boat in the ocean for a month or more at a time.

All of this can change at a moments notice but this system will give me more reaction time to wind gusts and keep the nose pointed where I want it.

I can hear the readers now, "That is too much weight for the keel structure to support.", but if some common sense is used and the ballast is reinforced and fastened to the keel and hull bottom securely, I should be in good shape.

I also will use Bondo putty for fairing the keel into the hull bottom and covering screw heads as it will also be sealed and protected with mat and cloth. I also need to use screws and drill holes in keel for the Bondo to adhere to when fairing the keel, besides the clean plywood and 1 by stock, blown clean and tack ragged.

Here's a quick image. I am open to advice and appreciate different views/ideas as always.

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Ray,

Do you have any special backers holding the keel to the hull bottom where you have placed your 370 lbs?

I believe that by spreading out the load and having a 3/4" plywood center in the keel [which is for strength around the lead and connecting the stem and stern post] and having large bolts at the thickest point forward going deep into the lead, I should be OK.

There will be a ga-zillion screws holding the original design keel onto the boat [over-kill] and I will be using larger screws and bolts only where needed over the larger lead area. Common sense and experience will get me through this as I am not concerned with loosing or distorting the keel because I added 440 lbs to it. I will have plenty of lumber around the perimeter of the lead along with fasters inside of the lead itself.

In the forward compartment I can have a 1X4 backer running along the center-line but I will have to wait and see. As you can see by what I have been drawing, I am taking in all of the suggestions available on this great site. The drawings are ever changing.

I have never used a forum for boat-building tips before but rather relied on memory, experience and common sense. The questions raised are valuable and make me think twice so I appreciate the input. Don't stop. OK?

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You have me re-thinking my idea and a 3/16" or 1/4"X3"X?" steel plate for the forward part of the ballast with through bolts is probably a good idea as I am rough on my boats.

These devices will be under 1 1/2" construction foam that can be morticed to accept any shape [steel backer, wood backer, bolt heads and nuts and washers] that is underneath.

This along with keel filets, mat, cloth and resin should hold the ballast in place while pounding through rough water and weather.

I thought that you had 370 lbs. I will re-think my weight needs and the ballast will take up less space.

Thanx again my friend. :roll:

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How does this look Ray?

Added stainless through bolts with a 1X4 backer running down center between panel joiners, downsized to 355 lbs. and shortened ballast by 2'.

Also moved the mass aft a little. After sealing and painting the interior I plan to insulate and add buoyancy to all exposed interior decks, ceiling and panels so I can easily mortice out for bolt heads, nuts and washers, joiners and backers.

I am far away from starting the build but the more I prepare for my model, the more I want to change.

Thanx for your input.

Norm :D

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I'm with Mike on this one, I reduced my Weekender mainsail sail by a foot and a half along the bottom. It made all the diference in the world over 20 knots. In highers winds I just let it flap and use it as asteading sail for the jib. However my keel is cypress and has soaked up a lot of moisture over the years (it lives in the water) so its pretty heavy, which makes it slow in light winds and very steady and smooth in big seas.

Basically I think the standard sailplans are way too much to singlehand in over 18knots, at 30knots you are also getting a lot of windage on the boat, I can never tack my boat in over 18. Wayne also has the same problem. But jibing in these conditions is much safer and just as quick.

However when I build my Vacationer I will definitely but some ballast on the keel, no a lot and not for stabitly or self-righting ability, but to give the hull a bit displacement which will give make it more seaworthy in a sea and more comfortable too. Of couirse with more corresponding foam bouyancy too - last thing you want if something does happen is the boat sinking on you!

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