sexta-feira, 16 de janeiro de 2015

Bolger Gypsy Sail Boat

As I have promissed when I decided to build a wooden sail boat, here are the details, photos and comments about this fascinating process and my evaluation of the results.
Once upon a time... well, you can read the beginning process in my first blog BlackFly Boat. At that time, I was looking for an ideal boat to build, considering my lack of experience. As a resume, I decided to construct a model, using all the steps of a real boat, aiming some experience before expend a lot of money. This step is told at the link above.
The model BlackFly and Gypsy
This stage was very importante, as I realized the type of construction I was choosing (clinker)  would be too tricky. After some researches, I decided by "stitch and glue" technique. At first glance, must confess, this technique seemed too basic for a guy who wanted to experience an ancient master boat building skills... But something whispers: "chill out, simplify".
Ok, I obeyed, taking my pockets in account. Looking for more info, I subscribed at Woodenboat forum and posted some questions about the ideal sailboat for the conditions where I live (Paraty, Brazil) and suggestions of plans using stitch and glue process.
Some folks presented me with some options, but at the end, I decided for a project very similar of a Snipe, the Bolger Gypsy.
Philip Bolger was a boat designer who made several DYS models, easy and not expensive to construct, having Harold Dynamite Payson as a builder and test-sailor partner.
The Gypsy model is one of its most successful Project, having considerable owners worldwide. The shape caught my eye as it had some vintage look. So I started searching among the owners the good and bad aspects relating this Project.
The plans are very cheap, easy to build and sold as a magazine that includes others Bolger projects. You can buy it at InstantBoats (direct from "Dynamite" Payson, which helps to carry his legacy) and  Woodenboat Store, among other places.
But it has few bad aspects listed bellow, but
  • When heeling, wavelets fills the boat with frequency.
  • Gypsy doesn´t have flotation chamber.
  • The daggerboard is out of center and some say it influences  the performance. 
  • The sail area is small (or adequate, depending on what you want).
  • The oars take up much space where they are planned to be.
Some owners customized their Gypsys, changing "waek" aspects of the Project. This made it a perfect option, as I could make my own changes, if necessary.
Part I: Transferring mesures
As you can see in the detail above, the plans are very easy to understand and I started transferring the measures to CorelDraw. In fact many builders do this process direct to the wood, but I thought it would be more accurate using a CAD program, or a vector one, as CorelDraw. Then, I plotted it in real size.
Using a sharp object, I transfered the points to the plywood (the base material for the structure). The Stitch and glue processes uses a plywood for the structure, covered with fiberglass and epoxy. In fact there´s a lot of core material today, as Divinicel, more light and easy to work, but too expensive for ordinary builders.
Making the cuts and taking the shapes alive. For better use of the surface, some parts were designed over a cardboard, allowing to combine the position of the cuts.
In Brazil, the size of plywood are different from other countries. So I had to adjust a bit this difference. But for those who live in USA, for example, where the plywood measures 6' x 8' , the magazine offers a plan mapping the position of each piece. Gypsy uses just 5 sheets.
Part II: joining parts
Before you start to join the pieces, first you have to make the plywood less spongy, otherwise, the fiberglass wont get glued over it and can delaminate under sun and water. The marine environment is extremely aggressive.
First you prepare some epoxy appropriated for soak the ply surface. This process is better explained in some sites with the subject  as "laminating wood, using epoxy over wood etc". But I think every human being on Earth will agree that the bible of laminating and constructing wooden boats is the Gougeon Brothers on Boat Construction Book, pioneers of West System, that covers any aspect of this type of process. This book was free for download at West System site, but unfortunatly, not anymore. Maybe you can contact the company or seach it on internet.
After covering the ply surface with the appropriate epoxy (some builders use just one type of epoxy for all the process), the spongy  wood surface will suck the resin, making a thin plastic coat, closing the wood cells.
Next step consists on assembling the parts. Gypsy uses supporting structures made of wood (like table legs) and connected to frame molds, this latter, part of the boat. Easy to do, not requiring complex structures to support the hull.

Parts after being soaked in epoxy and the molds attached to the side part and over wood structures.
The Gypsy process is so easy to build that the stitch process is replaced by tapes. To be more precise, I used wires and holes, as it should be, but Harold Payson surprise us, using simple pieces of tape, making the work very easy.
Here a detail of how to use the stitch (image from Matt´s Space)
Any book concerning boatbuilding considers the alignment an IMPORTANT aspect of the process. So, pay attention to this. The balance and performance of your boat will depend on it.
Checking the alignments

Left, the hull with parts connected. The long parts that compose
 the hull are made of small parts joined togheter by scarf process,
explained on Goungeon Book (see link above).

The scarf process consists on making bigger and long parts by connecting two small pieces. Since this long piece must have a strong connection, as they are structural parts, the connection has to have some special aspects. As you can see below, the cut on the edge of each piece must be done in angle, using a 1 x 8 ratio (some books say 1 x 10 or more). This means if you have a ply with 1/4" thick, you must cut the edge with a diagonal ending on 2" . Thus, you will have a bigger área to glue the pieces, making sure they have a strong joining.


At left, the scarf cut. At right, testing the strength on a scrap.
I use a trick to check if all parts are aligned and with the same distance at each side of the hull. First I make some marks on the edge of the seam, as you see below, then I find the middle where the parts are joined using a cardboard and measure the distance from this point to the middle of the hull. So I transfer this measure to the other side and it has to stop exactly at the seam of the other side.

As you see, the measure from the mark to the middle
has to be equal when rebated. If you take care when
cutting and joining the parts, you wont have problems
 and the boat will be in perfect balance according the plans.

After all parts together, I reversed the boat upside. Then, checked again the distances point to point, just to ensure the molds are perpendicular with the line crossing the hull center and parallel each other.

I used a thread from the stern till the edge of a mold. Moving this
distance to the opposite side, the measure must stop over the opposite edge
of the same mold.

The daggerboard case, before being connected to the hull.
This is a tricky part to do, specially laminating the inside.

Part III - Laminating

The first thing to do at this point is to reinforce the seams using a strip of fiberglass. The Instant Boat Book covers this aspects in detail. After that, the hull will be laminated in all extension.

Laminating process has its secrets, but as you start doing, you quickly get the hang of it.
There´s a lot of vídeos on Youtube teaching the techniques. The Gougeon book also covers it in detail.

The hull covered outside with fiberglass and ready for changes inside. At this point,
the inside wasn´t been laminated yet.

Part VI: Customising

As told before, many owners made some changes in the original project considering some aspects faced when sailing. My biggest concern was the possibility of water coming in when sailing. Taking advice from some guys, I started a research looking for a solution that didn´t change the basic plan, since I didn´t want any structural problem.

First, the boat had to have a deck. So, over the hull ready in its structure, I made some experiences using some battens till I find the perfect shape.

Here you can see the scrap wood used to find the ideal shape
and some molds (internal divisions) cut at its final shape.

I had to complement the original molds with a ply cut into a curved shape.
I made many reinforcements on the edge, where the deck would be fixed.

I created this simple gadget (homemade suta) to check the angle from deck to hull and transfer the measures to the opposite side.

When the shape was defined, I started fixing the final battens on place. As you see bellow, I made some holes in front molds to have access to the front room. The inside hull was laminated taking the care of seams reinforcements. After that, you must sand all the hull to brake the plastic surface aspect, making it more coarse (but not much, avoiding hurt the fibers).

Other aspect I think could be improved was the oar location. In the image bellow there is an example of a Gypsy built exactly as the original plans.

Image from Sailing Texas

The design of oars position take considered space and keeps rolling from side to side. I redesigned this detail and think I can say this is my contribution to the Project.
The next image shows how the oars are accomodated, held in place. Of course, if you get stick to the project, there´s no point of using it.

The slot created, makes easy to store the oars, keeping them pressed against the hull sides,
making better use of the room.

The boom was something that particularly bothered me. It was planned to be very easy to make and install, but it seemed like na indian bow to me. No problem about that, since it works very well and that is all that matter. But I was desiring something more classic, like a traditional wooden boom,with gaff jaws and parrel. So, I made this change, but  afraid it could cause problems for the sail performance. I took the risk. The worse that could happened would be making another boom according the plans. But worked perfectly.

A model using a similar Gypsy´s boom rig system.

Gaff jaws.

Part V: Painting

I´m not a professional on any boatbuilding subject, but I think the painting is a main subject on protecting the boat and fiberglass from being exposed to sun, salt water, humidity and other. The Instant Boat book shows the simple way, using simple painting, inexpensive way to have some protection. But since I decided to make some investment in time and money, I took this subject as crucial.

Searching at youtube I found videos from International Painting Company. In Brazil, we dont have much boat painting products. International is a bit easy to find and has some quality that worth the price. I called the technicians team that explained me each step and products used. Since I dont have much experience, I decided to follow the exact orientation.

First I covered the fiberglass with a thin coat of Galverette, a kind of primer used before the main primer (Intergard EPS). They claim the Galverette helps EPS to adhere with more efficience over the fiberglass. Some professionals in Brazil told me this is a loos of money. But, I´m not a professional... so I followed the manufacturer recomendations. This products have diferente names in other countries. I suggest you to check the company´s toll free .
I started the process inside the hull, considering I would cover the top side with deck, making the painting process difficult after that, specially in front room.
After EPS, sanding again.
After applying the Intergard EPS, I covered all the inside hull with na thin epoxy putty coat, made to even the surface. I dont know the product name in english, but it is used to make the surface smooth after sanding, ready to final paint. I think you can make this using epoxy mixed with some powder (again, I dont know the powder name, but here we call it industrial talc). Then, sanding and sanding....
Paying for the sins, sanding, and sanding.
There is something important concerning health that has to be said. Epoxy is very hazardous and I developed allergy to the product. I never had any allergy of chemical products, but epoxy caught me. Some inflammations, red eyes and strong itching, in legs and arms. It took me 3 months to get well. Sleeping was difficult and the aspect of my skin was terrible. Be careful, using gloves and masks.
The inside hull finished. The arrow shows the step mast
and mast partner. This details cant be changed as these are part of
the structural Project. The deck will cover it, not affecting
the original plans.
Hey International! Would you like to give me
a free supply of paint by this ad? At right, being careful.

1. The deck in place, cockpit, and hatch, used for inspection. 2. The way I bent the front of deck, impossible using a whole plywood. Here you see small holes, used for steel screws, strengthening the joinings. 3. hatch used for supplies, as anchor or cold drinks. 4. space for outboard motor. The Instant Boat Book says it accepts a 2 hp (up to 5hp) outboard motor. 5. bigger hatch, later covered with a lid.
Hull painted and ready to receive details.
Part VI: Details
The lid covering the hatch.
This floor could be considered a meaningless luxury but, what a style.

I made some wood Keys to fasten this frames in place, working under pressure.
To keep the water out, I install coamings.
Sheer guard, for shock protection.
A bit of varnish with UV protection.
To glue the Coaming to the deck I used Sikaflex 221, extremly sticky and
 a bit annoying to use (it grimes everything touched and
is difficult to clean), reinforced with some rivets.
Daggerboard case: detail  in wood.
Oar locks had to be lifted a bit using a piece of thick wood,
avoiding the oars banging the coaming.
Stailess cleats.
Part VII: Rudder
First of all, I have to say Gypsy plans were created to be simple, enabling ordinary people having fun, becoming boat owners in short time at low budget.
But, as we say in Brazil, "why simplify if we can complicate". So, with this theory in mind, I decided to make small changes at the rudder stock.
The original design, as said, is very, very simple and don´t require much to do.
The pics above show the original design. The rudder stock is a simple piece of plywood
attaching the rudder itself with a wing nut (images from Instant Boat Book).
The beauty of this project is based on the freedom you have to change small details without compromising the structural design or performance.
The way pieces are fixed and put together in original project seemed a bit fragile to me. I decided to reinforce some parts, as hinges, sandwiching the rudder between two boards. At first glance, stainless steel seemed to be a natural choice, but the price was impraticabile, as I dont have the equipment to cut and weld this material. I decided by carbon fiber, easy to work and I could mold it as desired. You can read some opinions about this subject at Woodenboat Forum, where I posted a topic, asking the pros and cons of this material.
Using a plastic film for better finish.
To get better results on carbon laminating process I should have a vacuum bag system. But I didnt... So, what to do? I developed a simple way to get close of vacuum result. After laminating and having the piece soaked in epoxy, I covered the work with a thin plastic film. The wet epoxy sticked to the plastic creating a surface free of air. Using a spreader I forced the excess of epoxy to the edges until the plastic get sticked to the table. The air can´t get in,  creating a similar vacuum system (not perfect, but with a nice result). After dried, I removed the film, as you can see above.
The diagram shows how this method works.
After cured, the piece can be turned upside and the method applied to the other side. Be awere to protect the table or surface (sticky plastic or contact paper is nice) otherwise you can get the piece glued permanently.
The final result is a strong and beautiful rudder. A camclet is used above to sustain the rudder lifted.
Part VIII: The Mast
Have I told you about the simplicity of Gypsy plans? Well, the mast couldn´t be more simple to build. The original plan uses two solid pieces of wood glued together and, thats all. But, why simplify... I made researches on how wooden masts are done and get to the octogonal strip system. Yes. It is very hard-working to do, but perfect. I have tried the mast proposed in the plans, then decided for a solid mast using a log and finally a square mast made of planks... I was a completely failure. They warped after some days. Maybe the weather in my region (extremely wet and hot) had something to do with. So, frustrated, I got up my sleeves and started a traditional way of doing good masts: the octogonal system.
This method consists on using 8 strips of wood (the measure depends on the size of final mast) with a groove cut in 45 grades at one edge. The strips are pressured together and  naturally arranged in octogonal shape (thanks geometry!). The incredible of it is how all the system is suddenly arranged in perfect simetry and straight alignment when locked together. It took a lot of work to make this 45 angle perfect cut, but after that, piece of cake... You can read at Woodenboat Forum the subject I posted about measures and changing Gypsy mast shape.
I put a solid piece of wood inside step mast as reinforcement, considering
the  strong power that will be acting on this point.

Mast shaped and ready for varnish. Besides being very strong
this technique makes light masts. 
 Part IX: Sail plans
 When I decided to change the boom, all the rig system had to be rethought. Talking to some sail makers in Brazil (not much professionals available), I told about the conditions I live (light Wind, protected bay) and the changes I have done. The Velas Cognac sail draftsman suggest me some sail models that could work.
Final design,increasing the sail area and adding a jib.

Some people wondered if the change in sail area could affect the boat balance and suggested changinge the mast position, but other experienced sailors from my region said the change would be too small to cause considerable problem. Indeed, they were right. I dont have much experience sailing, but I didnt noticed anything that could descredit the performance. I could sail perfectly inside the "close hauled" region.
Part X: Rigging
 I used the Snipe rigging as reference, because I feel they look very similar, although Gypsy is a bit narrow.
The Snipe: 1- traveler, 2. Mains Sheet, 3. Boom Vang
If you decide to follow the plans as it was designed, you dont have to care about all this pulleys, cables and rigging details. But, where is the fun?
Gypsy: 1- traveler, 2. Mains Sheet, 3. Boom Vang
Part XI: Last considerations
First of all, I would like to apologize for my misspellings. Unfortunately, I don´t have perfect english and feel myself open to criticism and orthography corrections. My goal is to share this experience and improve this informations, helping people as myself, who once toured several places on the web looking for boatbuilding details.
This experience was amazing, for I always had the desire of having a sailing boat. Be able of building it myself, with these fantastic results, make me speechless.
Gypsy plans are incredible easy to use, and the boat behave very well, fast, with consistente manouvers, balanced, responding quickly to wind changes. The customization didnt cause any noticeable changes in performance. The costs were a bit more than expected due to my investments in details as dacron sail, steel cleats, pulleys, best painting and so on. But for those who just want a fast boat simple to build, the original design will offer the same results. Everyone who saw Gypsy ready was amazed about it.
Once more I would like to thank Woodenboat Forum, without which my tasks would be much more hard and imperfect. Thanks Chip, for the gift and advices.
I think wooden boat building caught me up. Hope one day I can be able to build a bigger boat and travel the world.
Marcus Figueiredo
Paraty - RJ - Brazil