The "NANCY G" a surfboat /lifeboat to motorsailer conversion build in progress

As you possibly guessed i have been experimenting with the keel shape and method of attachment. Basically I am installing a hybrid keel set up. A full length 12" deep keel (6in. existing plus a 6in. cross sectional tapered full length addition to act as a base and support for an additional 12in. deep 63-010 series modified long foil and a slightly modified 63-010 series skeg. The idea being the foil part of the keel plus the foil shaped skeg will enhanse the lower performance associated with the long keel alone. The cutout between the foil keel and the skeg will also enhanse the tacking . In effect I have robbed some of the dept of a full keel and installed a foil keel/skeg combo in it's place. Will it work? in theory yes but the proof will be in the pudding. For what it's worth in my opinion a simple full slab sided keel would be all that is needed in a motorsailer build but as I have said before this will possibly be my last build and I'm having fun experimenting. If it proves to be a success, we all learn and gain.
Since my last post i have removed the male mold from the hull and did a few modifications to gain better accuracy and easier building. I removed the plaster nose and will be replacing it with a wrap around material (alum. or plastic) for more accuracy and ease of build. The ply. skin was removed to allow installation of full width bulkheads matching the width of the top and botton foils at each location along their length.( top photos) I have also tapered the edges of the foils allow better fitting of the ply skin on each foil edge which is necessary because of the cross sectional taper of the whole assembly.(bottom photos,) Note, the dark coloured straight edge bottom right photo shows how the top foil tapered edge-the bulkhead edge and bottom foil tapered edge should all aligh to result in an accurate foil shape. When tapering the foil edges it's better to overtaperthan under taper, but be very careful not to cut into the bottom edges of the top and bottom foils as these edges will maintain the proper shape of the foil. I used a table saw freehand to cut the bulkheads and a beltsander to fine tune the cuts.I used a beltsander to taper the foil edges following a free hand thum/pencil mark guide. The new mold is now ready to be mounted on the hull once it's proper longitudional location is determined.(photo)(CE & CLR calculations and locations in a future post), Prior to this I have to build the male mold for the skeg which will be my next post. One last item--when building these foil molds I use a 3/4 birch and or maple ply to obtain better and more accurate cutting and sanding.--Tnx Geo.

 

To keep things flowing in sequence I have decided to continue on the main keel foil and will post the skeg development and build in a future post. I previously indicated that I had removed the plaster of paris foil nose and would attempt to replace it with thin alum. sheet. sheet for ease of construction and accuracy of build. My concern, alot of thick plastering was involved and plaster of paris is difficult to work with due to very fast curing time. It would be challenging for the average home boat builder. I visualized wrapping the nose with thin. alum. sheet would be much easier. Tried it, not a good idea,even thin home construction flashing alum. sheet was just too difficult to form. However I did come up with a system that the average home builder should not find difficult. (Step. #1) Using regular house construction canned spray in foam i over sprayed the nose section. After allowing 24hrs. set up time I rough shaped with a hand saw about 1/8 in.plus proud of the foils edges. I then fabricated a sanding board whose length was long enough to bridge the width between the foils and sanded the foam even with the foil edges being very careful not to cut into the edges themselves. Notice the fan shaped sanding pattern, initally perpindicular to the keel then as moving toward the nose, finally ending up palallel with the leading edges of the foils.(middle and bottom photos) In this case for every 1 in. of forward movement of the keel bottom foil I worked 1.5 in. forward on the keel root foil. This takes a little patience but by using very course sandpaper on the sanding board it is a fast job. Next post Step #2. --Geo.

 

Once the 1/4 ply sides are fastened, we are ready for step 2 in forming the nose section. Using a heat gun I attach 1/4 x 3/4 in. plastic strips along and around the nose sections of the upper and lower foils. This builds the foil edges out even with the ply and acts as guides for the plaster of paris skin used to cover the nose shaped foam. Simply pour the plaster on the foam then using a long straight edge with the plastic strips as guides spread it over the foam nose. Once this plaster skin is cured the plastic strips also guide the sanding board where once again we use the fan pattern sanding technique. I rough sanded the plaster of paris nose section then applied and fine sanded Durabond 90 gyprock (sheetrock) crack filler to create a fairley smooth surface. I then skim coated with regular drywall (sheetrock) plaster and again fine sanded it for a very smooth finish. Once primed with several coats of red oxide metal primer,hand sanded with #400 paper, it will be ready for re install on the hull, waxed and glassed.

P.S. I realize I have gone back to using plaster of paris on the nose section but in this case it is only a 1/4 in. skin, as such it is much easier to work with. The foam essentially forms the nose section. Also the top center photo was taken prior to completion of the plastic strip on the lower cord. A piece was added to fill in to the ply. edge.

 

Typically in a modified rebuild or a boat conversion one runs into odd problems that require solving. The most challenging of these is replacing-- modifying -- or installing--items below the waterline-- especially the keel. This has to be strong enough to take tremendous side loads and withstand reasonable impacts plus support the weight of the entire vessel if one becomes grounded. The fastening of the skeg was such a challenge. The existing prop shaft tube prevented installing keel bolts for the aft 2/3 of it's length and I didn't want to remove the excellent factory installed glass tube. So I have come up with a plan making use of those short 1/2 in. existing bolts sticking up out of the origional keel.(first two top photos) That plus a couple more ideas which I will post on the actual install of the keel & skeg.The building of the skeg male mold is essentially the same proceedure as the foil keel. In the last two photos I have temp. placed the keel/skeg on the hull to confirm my calculated locations. I inverted one of the photos to get a better idea on designing the cradle. When viewing these keep in mind they are sitting on a 6 in. deep 9 in. wide existing full keel. An additional 6 in. of full keel will be added to the existing having a cross sectional taper to reduce the bottom of the full keel section from 9 in. down to 4 to 5 in. wide. This cross sectional taper addition will be blended into the foil/skeg sections shown on the photos. I will post info and photos on this future work.

P.S. If you look closely at the last two photos you will notice I have seperated about 12in. of the tail end of the foil shaped keel. It is shown as framed only without the skin. I am toying around with possibly designing this as a sort of trim tab,( I have to do more research) if not i'll simply glass it to the keel's after section .

 

All Right we're moving along dispite outside jobs to raise boat money, getting my firewood in for winter and organizing the old house and shop for the coming white stuff. The photo show the foil keel and skeg assemblies with 5 coats of red oxide metal primer applied ready for #400 sanding and 4 to 5 coats of release wax prior to glassing.

 

Posting will be very slow over the next 6 months (lifes interruptions) after which I will proceed with the the next part of the keel build. This involves building another mold, that will taper the wide existing keel (91/2 in.) down to 7in. and then incorporate the foil molds into it. Once the hull has been moved into the shops car port shelter I will proceed on this part of the build.The goal is to have the keel shell completed and attached ready for ballast installation in late spring,(2012). I will then build the wheeled cradle and move it all into the main shop for completion over the summer, fall, winter, spring, and launching summer 2013. (The year of my 70th. birthday)

 

Those "lifes interuptions" are a *****-keep the faith and good luck! She's looking real good. That will be one hell of a great birthday present!

 

Thanks Doug-- lifes a beach--(and fishing piers) St Augustine-Daytona- New Smyna--those in between --Cocoa--

 

To date -- completed building the shop big car port and moved the hull under it's roof for the winter. The 2500/3000 lb. hull was easy to move once a set of mobile home wheels and axils were temp. attached. A small excavator simply picked up the bow and moved it in place as if it were a two wheeled cart. I then installed a simple set of fence gate style doors in which I will install sheet foam insulation between the boards and tarp the carport sides to seal all against the weather. Normally I would have moved the hull into the heated main shop but I need the space for another 6 month project.Next step continue working on the keel .

 

Thankyou for steering me to your project. I'm impressed.And envious. My boat is in Florida and I am in Mexico. I wish I could walk out to my shop and work on it. Instead, I plan and save, then drive 1500 miles to Florida, pull the boat, on its trailer, out of the storage yard, set up in the DIY boatyard, perform the work, launch and test the boat,rework, retest,ect, then put everything away untill next time. The only advantages of doing it this way are a much much lower cost of living in Mexico, and I have to think and rethink before cutting any material. I certainly hope my project is finished before my 70th birthday. I'm only 63. Dave

 

Dave this is I think if my old memory serves me in addition to regular builds, maintenance and repair work for customers, conversion # 4 or 5. This is my last I hope, I've had this hull for 4 or 5 yrs.(which puts me at around 63 at purchase time) but life keeps getting in the way. This past year progress is slow but happening and should speed up and be completed in the next 20 to 24 months. Yup on your schedule you'll be on the downhill to 70 before completion -- Much thanks for the compliments-looking forward to some photos along with the work description ---cheers Geo.

P.S. another site you might find interesting is my forum batism of fire, "Reverse Engineering (conversions and modifications)------

 

Well got her in under cover. Installed a set of car port doors and pulled a tarp up to cover the open side. Started work on the male mold which will add to and taper the width of the existing full keel. Once this is stripped planked I will add the foil shaped keel and skeg sections. I should get this completed over the next couple of weeks.

 

I envy you being able to work on your boat but I don't even the weather coming your way.
Starting to get cool in mexico. Switched the AC to Heat 1st time today. Wife felt chilly. Pulled on a sweatshirt to walk to corner market to buy fresh tortillas, cigarettes (mine), 2 lt coca-cola, milk, donuts, avocados, bananas, and corazones (heart shaped cookies) for my wife. Spent $5. Winter is coming

 

Man don'tknow whats happening but we're basically working outside with little more than a light jacket on here. Temp. was 14 above two days ago . Other than a scattered day of rain i could laying up glass on the mold. Hope it hnags on for a few more weeks thats exactly what i'll be doing. The boys are still riding their motorcycles .

 

I'm happy for you. Hope it continues. I sailed on the Great Lakes for 10 years. I know how bitter cold it can get in northern climes