Thursday, September 1, 2016

A little color...

My decision to paint the exterior of the hull is purely utilitarian. Many of my friends have told me I'm crazy to not leave the hull bright. As it is I will have plenty of annual maintenance to do with the bright deck and interior. I researched the options and went with Epifanes two-part polyurethane, primarily for two reasons. Tests by Jamestown Distributors concluded it was the toughest of the products they carried and it was available in a huge range of colors. Choosing a color was difficult, in part because there were so many choices.


We will certainly be visible if the boat goes turtle. I followed the manufactures advice and applied two coats of epoxy primer, followed by three coats of polyurethane. Both products were easy to apply. I used an old high pressure spray gun at 32psi with the product thinned about 10%.


While the paint cures I'll put the trailer together and finish the spars.

Wednesday, August 24, 2016

Bottom's up...

There is an art to everything and varnishing is no exception. My experience with varnish and a brush has been, at best, less than gratifying. I kept working at it figuring I'd get better, but it always seemed like one step forward and two steps back. I came to believe it was impossible to get a smooth and relatively dust free surface with a brush. When it was time to varnish the deck I toyed with the idea of using a spray gun, but reverted to the brush which seemed like the path of least resistance at the time. After a number of coats, six to be exact, I finally acknowledged my insanity, doing the same thing and expecting different results.

I have a twenty year old spray gun, high pressure of course, but still serviceable. So I went online looking for advice on spraying Epifanes varnish. I couldn't find much info, even at the product website. Lots of advice on brushing. One article indicated you must use Epifanes spray thinner to get the right results. Taking no chances, I acquired a quart of the spray thinner.

My initial concern was that my spray tip would be too fine for the varnish. My concern was unfounded and it took only a little experimentation to get a good spray pattern with the product thinned 50% at 32psi. As I sprayed on the first coat I kicked myself in the kester for not trying this sooner. What took an hour using the brush I can spray in ten minutes with way better results. All I can say is better late than never. I added three coats to the six applied by hand and called it good enough.



While the deck varnish cures the plan is to paint the bottom. It is time to get rid of the strongback. I cobbled together a cart with 2x6's from the local big box and added a carpet covered cradle matching the deck camber. With the help of a few strong friends and family members we extracted the boat from the garage.

 

We rolled the boat on an air mattress for added safety and lifted it onto the cradle. I was very pleased to find the boat was much lighter than expected.


My friends look at me incredulously when I tell them I'm painting the bottom, but they won't have to maintain all that varnish. As it is, the transom, deck, interior and stem are all bright and will require frequent maintenance. I'll be spraying the hull with Epifanes poly-urethane. Teal green, my wife's choice.

Thursday, July 28, 2016

Almost there...

At last I'm down to the rub rails and coming. Happily, I had just enough 5/4 mahogany to get out the rails. The rub rail is 5/8" x 1" in section with a 1/2" radius top and bottom, basically a 1" bullnose. I tapered the rails slightly fore and aft as suggested in several of the boat building books I've read. The rails required some hand fitting, especially at the bow. I secured them with epoxy and 1 1/2" bronze screws. Lastly, the holes were bunged and flushed. The following photo shows some yet to be flushed bungs.


When it came time to fabricate the coming I had to make a choice regarding material. I was unable to source genuine mahogany in the length I needed (10 feet). I originally thought white oak would work well, but it's heavy and, more importantly, very difficult to cold bend, even when re-sawn to 1/4". I opted for African mahogany instead as it is much lighter in weight and bends easily. Fortunately, I was able to obtain a couple well matched boards locally. The coming consists of an inner and outer piece, each 1/4" thick. I applied the inner pieces first, then laminated the outer pieces in place.


With the coming in place it was time to finish sand and apply varnish. I sanded everything to 180 grit before applying the first coat of varnish, thinned 50%. The next coats are thinned about 20%. The Epifanes instructions call for 10%, but I find 20% works better for me. The stuff is incredibly thick un-thinned. The following photos were taken after three coats.


I'm finishing the hatch, also of African mahogany, separately.


A drip lip at the front and rear of the cockpit will divert accumulated spay or rain through small limbers in the coming.


The coming angles outward about 8 degrees in an attempt to provide a somewhat comfortable backrest when seated on the floor.


I plan on eight coats of varnish before flipping the boat and painting the bottom. To say I'm anxious to get her in the water is an extreme understatement.


Thursday, April 7, 2016

About time...

I've neglected the blog for awhile but progress has been made, albeit slowly. The deck is now covered with 6oz fiberglass and epoxy. I took the following images after the third coat of epoxy.


The rough surface will be finish sanded before applying varnish.


I will need to flip the boat and paint the bottom before installing the coaming and hatch. The centerboard and rudder foil will also be painted to match the hull.


The rudder has been an interesting project. In keeping with my tendency to make things more difficult, I decided on a retractable rudder instead of the simple barn door type specified in the plans. To this end I added a retractable foil, keeping the general shape and size of the barn door arrangement when the foil is up. The foil is manipulated by a single line, in the form of a loop running up through the tiller, and attached to the foil at both ends. (the small holes)


The foil will pivot on 1 1/2" round high molecular weight polyethylene. The white colored material is epoxy strengthened with silica. Before the foil was glassed I drilled oversized holes and poured the epoxy. After the epoxy cured the foil was glassed and the actual holes drilled, creating a hard waterproof barrier.

 
The finished product.
 
 
The foil is shaped like a pulley at the top to accommodate the control line.
 
 

The pivot rod is attached to the rudder housing, shown below, with a 1/4" carriage bolt. 


The housing must be water tight, so all surfaces are glassed. I had to do this in steps. The center layer is 3/4" mahogany with glass on both sides. The outer pieces are 3/8" mahogany, also glassed on both sides. The center layer contains two 1/2" x 1/2" channels for the control lines as well as two sheaves to redirect these lines. These can be seen below.


After sealing the channels with 3 coats of epoxy I applied cover strips and another layer of fiberglass. Now I'm ready to glue on the other side.

 
Another view of the internals.




The tiller attaches to the tenon shown below.


I had some nice maple laying around which I combined with mahogany for the tiller.


The slots seen on the top will accommodate sheaves for the foil control lines.


A closer view from the top.


My next chore was to fabricate the boom and gaff spar. Both are solid Douglas Fir and tapered. This provided a chance to have some fun with my hand plane.


I was very lucky to find such wonderful straight grained material locally.


The boom (shown below) is 11' 6" in length and tapers from 1 1/2" to 1 1/8". The gaff spar is 8' in length, tapering from 1 3/8" to 1".


Both have wooden jaws that fit around the mast. However, the angle of the gaff spar requires a slightly different shape.


I used a very hard wood, known as Pau Ferro or Morado, for the jaws. This wood comes from South America and is very durable.


Next up, paint the hull...  oh boy!

Thursday, October 22, 2015

Deck On...

I've heard Colorado described as "everything but the ocean". I agree and make it a point to vacation by the ocean whenever possible. One of my favorite destinations is Port Townsend, Washington, for the annual Wooden Boat Festival, held in September. This year my wife and I made the trek again, having missed the last two years. The weather was fabulous and we enjoyed the festival as always. The folks who run this festival really know what they're doing.


If only I had one of these...


Or this one...


I always leave the festival inspired, thinking of the boats I could build if I just had a bigger shop, more time, and an unlimited budget. When I mention this to my wife she just gives me that look, the look that says you've got to be out of your mind, just finish the project at hand. It is good to dream...

Back in the shop, I'm down to the last few pieces.


The day I glued the last strip in place was one of great celebration. At last, she looks like a boat.


I've got some leveling to do before I can apply the glass. I'll use a cabinet scraper first, followed by 80 grit on the long board. There is no shortcut to hand sanding with a long board if you want a really smooth, even surface. Horizontal surfaces will magnify every blemish or inconsistency. I'm really looking forward to seeing what the deck will look like with finish.


When sanding, I'm careful to keep moving so not to spend too much time in one area. The goal is to evenly remove material from the entire surface, keeping the overall shape intact and removing only the minimum amount of material necessary. I don't try to get it all in one pass and I'll stay with 80 grit until the entire surface is uniform. It might take several passes to get there. The pictures above were taken after the first pass and you can still see the darker low areas. When the surface is completely uniform, I'll move to 150 grit and finally 220 grit.


Before I glass, the deck must be flush at the sheer, cockpit, and hatch. I used a flush trim bit and will finish up by hand.

Since the beginning of this project a source of indecision has been the "traveler", or "horse" as they call it in the UK. My plans show a rope traveler, but I've decided to go with bronze one instead. I started with a 6' piece of 3/8 silicon bronze rod. I fabricated the jig from a pattern made previously for laminating the deck beams. First, I carefully cold bent the rod to match the shape of the deck and secured the rod to the jig with hose clamp material.


I've never bent bronze using heat before, so I looked online for advice. It's pretty easy, basically heat it up and bend it.


I'll trim the legs to the desired height and add some threads. When this is done the rod will need to be annealed. This means heating the rod again and allowing it to cool slowly, in order to remove internal stresses and toughen it. Finally, the rod will be polished to match other bronze hardware.

Friday, August 14, 2015

Just a few more strips...

If you want to build a boat quickly, do not take my advice on anything. Once again, I've succeeded at finding the slowest way, in this case, to build a deck. However, all good things must come to an end... eventually. I'm not there yet, but closer.



The deck will be covered with 6 ounce glass. I'm looking forward to that moment when the sanding is done and I apply the first coat of epoxy. The moment of truth, so to speak, when the true beauty of the wood is fully exposed. I'm hoping it will inspire me to want to varnish, but I'm not betting on it. Have I mentioned how much I like to varnish?




I'm going to try spraying varnish on the deck instead of brushing. While varnishing the interior of the hull, I struggled to find the optimal ratio of thinner and/or retarder that would deliver consistently good results. Any change in humidity and temperature seemed to necessitate an adjustment to the mix. In short, I was never totally happy with my efforts at brushing it on. Having nothing to loose, I'll give the spray gun a try.




The wife and I have made plans to attend the Wooden Boat Festival in Port Townsend this September. This is the event that first inspired my ambition to build a boat. Lots of really cool boats and interesting people in a beautiful maritime setting. Highly recommended!

Tuesday, April 14, 2015

Clamp-it Jed

My plan for the deck was theoretically sound, but I admit I had second thoughts as I ripped two gorgeous 5/4 x 10 1/2" x 11" mahogany planks into 3/8" x 1 1/16" strips. The planks clearly came from the same tree, perfectly matched in color and character. In a way, I regretted using such wide stock for this purpose. I thought these boards might be better suited to a fine furniture project. I was wrong. With each cut it became more evident the boards were under stress and would have been very difficult to work with in larger dimensions. The strips came off the saw like French fries. Thankfully, the curved pieces proved to work to my advantage.

My first task was to create 10 pieces at least 16' long. I used a 12:1 ratio scarf joint to do so. After gluing, I planed the strips to a finished thickness of 5/16" and a width of 1". I found this thickness to be a happy compromise as 3/8" seemed too thick and 1/4" too flimsy. I want the deck to feel firm under foot, but I also want to keep the weight down. These long pieces will be used around the outside of the cockpit and must be carefully dry fitted to get the exact length right.

I pre-finished the bottom side of each piece with two thick coats of epoxy, sanding before and between coats. Then the strips were planed one more time to a finished width of 15/16". This dimension is another happy compromise based on bendability. Next I applied a protective caul, where the rub rail goes, to clamp against. I also made some flexible wood strips to protect the inside edge. These I coated with wax to prevent epoxy from sticking to them. At this point I'm ready to dry fit the first piece.

When cold bending, the key to smooth results is a little pressure in a lot of places. I knew right away that I didn't have enough conventional type clamps. However, I did have about 30 homemade clamps that I had made specifically to glue acoustic guitar tops and backs on. The clamps are fabricated from 1/4" x 6" carriage bolts with wing nuts and wooden washers. Not much clamping pressure, but plenty for this job. They weren't long enough to do more than one strip on each side, but this would be enough for a test. I then ordered 50 - 5/16" x 10" bolts with wing nuts to make a larger version of the clamp.


 I learned a lot dry fitting the first piece. I started at the transom. Thank God for my compound miter box, a most useful tool when boat building. The transom angle is a steep 47 degrees by 14 degrees. I clamped my way forward until I could place an accurate mark for the other cut. The cut at the bow is roughly 34 degrees by 2.5 degrees. In this case too short is better than too long, but my goal is just right. A slight bevel must be added lengthwise to accommodate the curvature of the deck, otherwise the joint will not be tight on the top. The bevel is about 1 degree and is only needed on one edge. When all is right it is time to mix the epoxy.


I'm using MAS flag epoxy which is thicker than the formula for filling fiberglass. I'm amazed at how strong this stuff is, the wood will break before the epoxy gives. One key to clean epoxy work is learning how much to use and some trial and error is always necessary. I found a small foam brush worked for me as an applicator. You need to see a little squeeze out to be sure. I keep a rag and some acetone handy and wipe any excess as I go. If one is careful there is very little left to clean up. After all the clamps are in place I inspect to make sure the piece is aligned lengthwise as close as possible with the previous piece. The epoxy can be a bit slippery and the strip will sometimes need re-adjustment.


 I found some down pressure was needed over the king plank and at the transom. After the first few pieces, and some obligatory cursing, the process started to become routine. Once I hit the cockpit the process should become a cakewalk as the pieces will be much shorter and will not have to fit perfectly end to end.