Panel Layout

Click on a picture for a larger view.

OK, after we have constructed the table to our satisfaction, we have to lay out all the material to make a panel.

We first have to make a template out of non stretchy material, something like Mylar or anything that will not tear easily or absorb moisture and change shape or size. This template is made from a set of offsets provided by Derek Kelsall.

A set of offsets contain all the measurements for the hull shape. There will be a center line and a design water line and a shear line and all measurements will apply to these lines.

This is what a table of offsets looks like. This is not the table for this project, but you get the idea.

Here is the template laid out on the table. You can see the center line, some station lines and the upper and lower tangent lines. The left edge of the template is the sheer line. On the right side of the template you can see the dart lines in red.

On this next picture you can see the center line, bow profile, first station line, marked O, and the upper and lower tangent lines.  

Before we go too much further, we should talk about this interesting device.

This is how we make the deck edge radius form which allows very easy mating and attachment of the deck to the hull sides. This template is made up by covering a 3 X 3 inch angle of aluminum with packing tape as a release agent. Then we cover the inside of the angle with a couple of layers of 10 oz glass and resin. After it cures, we remove the template from the angle. We now have a 3 X 3 angle made out of glass. We fill the inner section of the angle with a mixture of micro balloons or talk and resin and press it up against a 6 inch diameter piece of PVC pipe that is also covered with wax or a release agent. Removing the pipe after it all cures, leaves you with a template for the deck edge radius. You will need varying lengths of this template so you can make a few at 8 feet long and join them along the sheer edge as you need them.

This is the way the deck and the hull sides go together. You will have to trim one radius to fit the other and then you can glue the two edges together with a modern adhesive. No bolts-no leaks.

Here we are rolling up the template after placing the deck edge radius former in the foreground, The form for the stern rebate on the left of the picture and you can see a dotted outline at the top of the picture that is the bottom edge of the panel.

Now we can see the layout a little more clearly. Deck edge radius former in the foreground, stern rebate template on the left. The blue tape pieces show the outline of the panel.

Here we are preparing for the gel coat to be put down. We have the deck edge radius former on the left, the bow rebate template at the bottom of the picture and the solid blue lines are the edge of the gel coat area. Again, the dotted blue line is the extent of the bottom of the panel.

The bow and stern rebates are to facilitate forming the bow and stern once the two halves are put together. These rebates must be cut into the foam as well.

The gel coat is being rolled on the waxed surface of the table. Since this is the first layer of our panel, it will be on the outside of the hull. This one operation saves many hundreds of hours of tedious sanding and fairing the hull to obtain a smooth finish on the hulls of a 42 foot catamaran.

We want to remove the tape before the gel coat gets too hard as this will give us a nice crisp edge. If you wait too long, you will get a ragged edge which sort of ruins the whole idea anyway.

You can see by the dotted outline of the panel, there is a considerable area that does not have gel coat on it. This area will be under water and gel coat is not used under water.

Look at that nice clean edge. Tape removed at just the right time.

OK, time for the first layer of glass.

Getting started with KSS

Building a boat hull using the KSS principle is very simple once you understand the procedure. It is a little hard to realize how a flat panel, built on a table, can make a hull formation with a rounded bottom and fair curves, but it does work.

I attended the KSS workshop in Tennessee this year and participated in producing half a 42 foot catamaran hull in a ridiculous short amount of time. I know that building a hull is only part of the time required to produce a boat, but after building a 37 foot Searunner, I know that it takes a long time to build a hull using the bulkhead and stringer method that can then be turned over and the work inside the hull gets underway.

I think one aspect of this method that will appeal to an experienced builder is the fact that everything is done dry on a flat surface that is easy to work on. You can reach any position on the table to position material, adjust lines or what ever you have to do by just walking around to the other side. This is a lot easier then walking all over your work and messing up the alignment of foam, glass, etc.

Another advantage is that everything you do is dry. That means that you can make changes any time up to the application of resin to the panel. Made a mistake on the glass orientation, disassemble the panel to the point of error, fix it and then reassemble the panel. You are not rushed at any stage of the panel assembly as nothing is final until you apply the resin and then it is all done at once, top, bottom, ends, everything.

we will get into more detail as we go along, but first, let's talk about the table. Here is a picture of a table half constructed so you can see the structure. Click on the picture for a larger view.

It is very important that the table is constructed strong so that it is stable and has no air leaks through the table where the panels meet. Using a biscuit joiner or some such will help with the alignment of the panels and using a good quality glue between the panels will help with the air leaks. A doubler of about 6 inches wide is placed below each joint and it is glued and screwed to the bottom of each side of the joint. The panels used here are 3/4 inch Melamine surfaced. The Melamine takes the wax and makes a very nice smooth surface for the gel coat on the panel and helps eliminate a lot of fairing later. Another all too unpleasant a job that is done away with or at least reduced to a minimum by using KSS.

The table needs to be a few feet longer than the panel you are building. Steve and Larisa are building a 42 foot boat so their table is 44 feet long. A couple of sheets extra for butt blocks so maybe 13 - 15 sheets for this setup.

Here is the finished table with a template to get started. The tape on the joints between the panels is to help with the air leaks.

I found a company who supplies farms with heavy duty white plastic sheets 10 feet wide by 50 feet long and 1/8 of an inch thick. This large piece of plastic is rolled up as a drum, with no creases or bends and would roll out on top of the table to eliminate any problems with air leaks. I have yet to find out the price of said sheet, but have asked for a quotation.

It gets better and better

I was most impressed by the last half hull Steve and Larisa built but the next one was even better. In Steve's own words again.....

Infused with 9.6 gallons resin in 35 minutes.
6-7 hrs of prep time today
3-4 hrs yesterday
4 hours before that

I am no expert, but you will have to agree, this is one fast and relative easy way to produce a hull for a boat. To help you understand the process, I will lay out the steps to produce one hull for a catamaran in my next blog entry.

Was I ever wrong

My calculations were way out to lunch. Steve and Larisa have completed a second half hull and here are the times in Steve's own words.

Let's see. Two people 

   Two easy days to cut and prepare

      Cut and prepare foam

      Rough cut glass

       Prepare tubing

       Gel coat the night before infusion

       14 hrs

   One day to infuse

       7 hrs

   Remove bag, peel ply, etc

       2 hrs

   One day to groove and put on frames -3 hrs

   One day to bend and glass -5 hrs

   Remove from forms and take outside about 3 hrs

    Extra help 5 hrs ;-)))

    Computer planning 2 hrs - used the Turbo-cad program to calculate the fiberglass cuts and resin line lengths.

14+7+2+3+3+5+5+2= 41 = 40-50 hrs

When working we do not waste much time. 

The bending is real fast and easy. 

Larisa and I raised the panel onto the forms by ourselves. A couple 2x4s and concrete blocks helped.

Larisa and I removed all but the last 4 forms but had help for 30 minutes to lower to table and haul to back yard. 6 people can easily carry a half hull. With a good two wheeled wheel barrel I think two people could move it, definitely 4.

2nd panel easier than first.

So.....we are looking at 40 - 50 hours for two dedicated people to build half a hull or 100 hours for two people or 200 hours for one person to build two half hulls. Of course even two people need a bit of extra help once in a while and the two have to be joined together. But really........the small amount of time spent to this stage is ridiculous to anyone who has built a hull the conventional way.

I guess the best thing to do now is start at the beginning and go through all the steps to get to this point.

Changing Horses

There has not been a lot of work done on the boat for a while, mainly because I've had a change of heart as to the construction method and material to build the boat. I built Rattle and Hum out of plywood and epoxy and am very familiar and confident with this building method. I felt plywood would be acceptable material for this boat.

Since building Rattle and Hum, I considered other methods of boat building but they all looked too expensive and I did not have experience with the material. One material that caught my interest was foam for a core and polyester resin and fiberglass cloth for the skins. Most production boats are built with this material so there must be something going for it.

The commercial boat building industry uses female or male molds to shape their hulls and I could not see myself spending all that time and effort to build molds for one boat.

I had heard of Kellsal's KSS method of hull building but did not understand it so basically dismissed it as a possible technique for my project. One of my boat building friends mentioned KSS again and suggested I check into it more closely. I bought a DVD from Derek Kellsal and was fascinated with what they were doing. The DVD was of one of his workshops where they built half a catamaran hull in one day! ONE DAY! That had to be a misprint or something. You can not build half a catamaran hull in one day.

I started to explore this KSS thing to see if it was hype or what. The more I studied KSS the more I was convinced I could do this. I still was not sure about everything I read, but the concept looked doable. The only way to be sure was to attend one of Derek's workshops and see for my self. Steve and Larisa Becker are building a 42 foot Kellsal and were having a workshop at their shop in Tennessee near Knoxville in October so I decided to attend and see what this was all about. Go to http://www.ksstennesseeworkshop2010.com/photos to see the photos of the workshop. Click on user galleries to see all the albums.

Well, we did it. We built half a 42 foot catamaran hull in 15 hours. It took another 8 hours the next day to shape the bottom of the hull so all up 25 hours. Of course Steve and Larisa had done a lot of prep work so that when we arrived, it was full steam ahead on the building of the hull. Nevertheless, if the other half took another 25 hours and maybe another 10 hours to join the two halves together, 60 hours to build one hull is unbelievable.

OK, back to reality. The 15 hours to build the half hull is really 15 X 7 people = 105 hours if you are doing this yourself and the 8 hours of shaping is 8 X 7 people = 56 hours. Still, 161 hours of effort to produce one half of a 42 foot hull is amazing. So, let's see 161 hours for one half, plus 161 for the second half and say 80 hours to join the two halves together is 402 hours. Now a lot of the people there were not always busy and there was a lot of gabbing going on, about how this works and how that works so I would estimate one person working along could build one hull in 200 hours.

Of course the hulls are not the whole boat and there is a lot of structure to be built after the hulls are complete but in my boat, the hulls are the major component of the boat as there is no center accommodations to consider. This could save me a couple of years of build time

Building schedule/Before KSS

For this project to succeed, you have to go about it in some sort of order. You have to consider how things go together, what you have to do first and all along the way. There are things that have to be done first or other things will not fit. Also, there is an easy way to do it and a hard way. I much prefer the easy way but have been known to choose the hard way. I decided to build one hull first, all the way to waterproof so I could store it outside while I built the second hull. The shed might be wide enough to build one hull while storing the other inside but I will not know that until I get the first one built. The third large project will be the center deck area and the connecting beams, cockpit, hard dodger, and bimini and that will have to be built after the two hulls are finished. The final assembly will have to be done outside the shed as the shed is only 20 feet wide.

I decided to build the starboard hull first. The detail of the first schedule is build the bulkheads, then cut the bulkheads apart at the spray rail level. This will allow me to install the lower portion of the bulkheads on a strongback and build the hull upside down and be at a comfortable height. If I do not cut the bulkheads, the keel will be 9 feet in the air when I start to build the hull. Of course, once I turn the hull over to complete the upper hull sides, the cabin top will be 9 feet in the air but I will be able to work from inside the boat and that will give me lots of standing space.

While writing this section I thought of an alternative method of construction, cut the bulkheads off at the sheer line and that would give me a 60 inch height to the bottom of the boat when it was upside down. The keel would still be above that by about 1.5 feet. It might be easier to build the hull all the way to the sheer line while it was upside down. Thinking this through, I realize that if I put the stem and stern in while the hull is upside down, I could glass everything before I turn it over. The other way, I will have to put the stem and stern in after it is turned over and then finish the outside of the hull when it it upright. It would be much easier to finish the hull while it is upside down. See what I mean about thinking things through. I will build to the sheer line upside down and finish the outside of the hull before I turn her.

Next Step

After you have decided to build a boat and bought the plans, the next thing to do is find a place to build her. A boat that is 38 feet long and 23 feet wide needs a bit more then a garage or car port to build it in. Unless you live on an acreage and have a few outbuildings, you will most likely have to rent something. I was looking for space for a couple of years before a shed became available at Shelter Island Marina in Richmond British Columbia. Shelter Island is a commercial yard and things are expensive.

Shed cost 4500 dollars, used,  and I still have to pay 650 dollars a month in rent for the space the shed sits on.

One big advantage is all the trades people you might need are there, welders, riggers, fiberglass workers, etc., and there is a store for small purchases. You do not want to buy any production material at the store as it is also expensive. But you know, a few of extra dollars at the store might save you a couple of hours driving when you need just a bit of something.