Having to take some time to get the cash machine cranked up again so little progress on the boat.
Have put several hours into fairing the foam on the first rudder after making a series of saw kerfs down the length of the blade with the depth set according to the templates screwed onto the ends of the foam blank.
After slicing the foam with a blade to the rough shape I've been using a 'Shure-Foam' plane to shape the blanks to within an 1/16" of the guide marks and then using a longboard with 40 grit. Goes pretty quick. The foam is amazingly loud to sand so Led Zeppelin has needed a bit of extra volume to keep things right. For some reason, sanding to Physical Graffiti, Volume I has been more productive than Houses of the Holy.
Friday, December 15, 2006
Having to take some time to get the cash machine cranked up again so little progress on the boat.
Sunday, December 03, 2006
Epoxy cure times are quite lengthy based on a shop temperature of 60 degrees. Getting into winter here in Maine the shop is rarely at 60 and usually well below 45 when not in use. Epoxy will take days (if at all) to cure at these temperatures.
Clogging the sandpaper up with three swipes is frustrating at best so a solution was needed.
As an alternative to heating up a sieve-like 3200 cubic foot shop I built a 5' x 10' x 1' box out of 1x3's and some styrofoam we recycled from some work done to the house. The R value is a mere 5 on the foam so we lined the inside of the box withthe radiant heat insulating bubble wrap to bring the R value up to 15. With a small heater and an unsealed (at this point) box (oven) we still got her cooked up to 90 degrees with a whimpy Walmart heater in about 20 minutes. This should cook the epoxy in 4-5 hours according to the specs.
Also applied the first layer of epoxy box. First time I've bogged anything. Quite nice. I say this now but I can imagine it becoming less romantic after a while. I tried the West System 407 which is #2 (behind 410) on the light and easy to fair scale. It's off the charts expensive but I thought I'd try a small bit as something to compare my own mixtures to. We're going to try the SM Fair and a concoction of 3 parts microballoons and 1 part aerosil (cabosil). Since fairing is going to be like a step parent it seems like one should learn to get along with it and make the best out of it.
Hard to imagine a baker not thoroughly enjoying himself on a bogging project.
A bit of school of hard knocks today as the E-glass decided that a strong relationship with the plywood spokes was not in it's best interest. One could say that the relationship was doomed from the beginning with the plywood not getting nearly enough of what it needed to form the strong bond. Enough epoxy. Laminating 101 was forgotten as I rolled out the glass on the table and layed it directly on the spokes without wetting the spokes out first.
I thought about it in bed last night thinking there would be a problem and sho 'nuff. Peeling the glass off the plywood you could see dry glass where the plywood sucked the resin out of it. A minor screw up so no sleep lost on this one.
I imagine there will be many such 'learning endeavors' along the way. The goal will be to mitigate the losses and keep the errors under control.
Layed the goal out for December to finish two rudders and two wheels. This would be a good first month in my book..
Friday, December 01, 2006
Wheels seemed like a good 'small shop' project so we've begun tackling them over the past few days. The plans called for laminating 8 strips of 1/8" plywood over a male mold for the rim however the yard was out of 1/8" so we're going to use more of the corecell. I've added and extra 1/4" to the diameter of the rim since my meat puppets always got tired on the weenie 1" diameter wheels.
Since the foam rim is going to be flimsier than the laminated plywood we'll need to add a bit more glass. Probably getting too clever here in using the foam but this is part of the fun. Until my noodle rim becomes useless that is.
The hub is a 7" diameter of 3/4" ply with a groove in the edge that the spokes will fit into.
The router is starting to meet it's maker as it is falling apart at the seams. The switch broke yesterday so it was removed from the equation and the 'Z' adjuster is starting to wear out. The locking mechanism also died. At some point a router is nothing more than a spindle. I think I'm there. I've had this router for several years so it's time for a replacement. The Ryobi stuff seems to be a good brand to learn with and then move on to something a bit more robust and with a dust port. It's amazing how much dust a router can spew!
Also filled the slot in the trailing edge of the rudder with some chopped fiber and and epoxy. A bit of a deviation from the plans here that called for glass in the slot but I liked the idea of having the slot be void free and I'm not sure I could have done that with the glass.
Lastly, got the spokes crackin' today. The jigsaw had a lovely time trying to get through 1 1/2 inches of plywood for the spokes. Everything is taking a bit longer than I'd imagine since everything is a learning process at this point.
So far boat building has been 80% jig building. Getting the router sorted out to cut rounds took a while as did sorting out a way to get the groove in the side of the hub.
Very rewarding stuff when the jig is set up and the part comes out as planned.
If I were to start over with the wheels I might try simply cutting and shaping the wheel core out of plywood or foam, glassing over it, adding bog and then painting. Building the wheel by building up a rim, hub and spokes is an effort. However, I liked the idea of having the hub be offset from the rim and this seemed like the only way to do it and the plans were as such. Once more, the Harryproa boys have already built it this way so it seemed like re-inventing the wheel (how often does that fit literally) would have been a road with more 'learning opportunities".
Wednesday, November 29, 2006
A few more hours on the first rudder. Most of which was firming up that a table saw is a must! Trying to saw a kerf in the trailing edge of the rudder with a straight edge and a Skilsaw was pretty futile. Wound up building a small router table and using a fence to rip the 6mm (should have been 3mm) slot for the epoxy/glass that will make up trailing edge.
Fairing templates cut and shaped as well.. Bench sander made quick work of these 6mm plywood forms.
Friday, November 24, 2006
Laying the saw into the first piece of foam yesterday was such a great feeling. After five years of dreaming, 12 months of planning to make it happen, 9 months of finding a home and moving east, 3 months of sorting out a shop and finding a way to make ends meet it was such a wonderful feeling laying out the first piece of foam and making the first cut towards the boat. Building the shop was wonderful and will continue to evolve, Rockler and Grizzly tool catalogs have overtaken top catalog position from Victoria's Secret (not by much) and adjusting to this wild place has already taught me lessons about cadence in life. But making the first cut towards the boat seemed like a milestone. So this milestone I shall record since this long project will be about celebrating milestones.
So the foam for one of the rudders has been cut and lamninated and will go through it's paces. Today we'll have a small celebration in honor of the first offcut.
We also had a little porcupine show up a while back.
Tuesday, November 21, 2006
Friday, November 17, 2006
Definitely should have bought that table saw and/or jointer I mentioned last time around. Trying to get a nice straight edge on a 12 foot 2x6 stick with a 3/4 HP Ryobi router was something akin to bringing a knife to a gun fight. Especially since my other bench is an eight footer so each stick needed to be set up twice. Although it took a bit longer to prep the lumber the edges were nice and straight.
I wound up snapping an offset chalk line from one edge, tapping small nails onto the chalkline and then setting the straight edge (I used a 12" section of particle board, very straight edge on the manufactured side) against the nails before screwing into the 2 x 6. Then it was time to let that .75 HP cutting beast of a router work it's magic. A bit of carbide on anything along with a straight fence makes for a decent cutting tool so it all worked out ok.
The plan initially was to use the i-joist used in floors which is a 12" particle board web sandwiched between a couple of 2X2's. Quite pricey and after looking down the edge with a discerning eye it was not as straight as I would have thought.
After prepping the lumber the frame was built to a reference datum that was an imaginary plane established 39" off the floor using monofilament line and a line level. Worked pretty sweet. Was nice having the 3500 pound mill in the area to adjust Z. Being able to adjust anything in .001" increments is always nice although a bit overkill in this case.
Top is 3/4" MDF and it will be finished off with a lovely bit of formica in a couple weeks as soon as it arrives. Options were to cut and paste three 4x8's and deal with the seams (which often seem to be a source of vacuum leaks) or to go with one sheet of 5x10 and a two week lead time. The virtuous option won out here. Measuring out afterwards it apears that the surface is flat within 3/32". Not perfect but adequate over a 10' surface. That's less than .001" per inch. Feeling good about that.
I took a bit of extra time getting the table as flat as possible for a couple reasons. The first nd most obvious reason being that I wanted flat parts. The second was that I viewed this as a good warm-up for building the strong back which will be built using the same methods. This was my first attempt at building to an elevated datum instead of upside down on a concrete slab (our slab is more warped than Mark Foley in a high school internet cafe).
Even though these intial projects aren't putting the flavor of a Pina Colada into the gullet they are rewarding and feel like the type of projects that build skills. I'd rather play around with straight and true on a bench than on a hull.
Next...On to the rudders (I mean it this time)..
Monday, November 13, 2006
Photos of vacuum pump setup. One large GAST pumps capable of pulling 28" and one smaller unit capable of pulling 22". Not sure what the rated CFM's are. Plumbing from pumps to traps are 1/2" schedule 40 PVC. PVC on top of the GAST pump is a cover for the start capacitor.
About $225 for everything here.
A few months back E-Bay presented a GAST 3/4 HP vacuum pump for $70. It was missing the start capacitor, capacitor cover and air filter but the pump was like new. I believe it was used in an R and D facility. So the pump was purchased along with a few tidbits to get her in shape and we have a $700 pump for about $110. I'll refer to the extra $590 as foam credits. It used to be beer credits ($3.50 per beer) however since this project started everything is about the $4.00 sq/ft foam cost. So we just picked up an additional 150 sq feet of foam. Total foam requirements will be about 1,600 square feet of 3/4" foam.
The idea of lugging this pump (75 pounds) around the shop seemed like a good way to break something (ie. my toe) so we put her on a cart.
I came across another smaller pump that will be used as a back-up. So my 2 hour cart project turned into a 6 hour pipe-fitting project since I wanted to tie everything in together. I gave back several foam credits on this one but%
Thursday, November 09, 2006
'Part I' hit on what possessed the decision to choose a proa. Here I'll touch on why a Harry-style Visionarry proa.
For a detailed description between the four proa types, refer to Cruising Proa Concepts
We made the decision for five reasons:
1. The idea of having the accomodations separate from the sailing loads made sense to us since it maximizes the accommodation space without having structural members and a mast in the middle of the salon. Additionally, having the living accomodations in the weather hull maximizes the righting moment.
2. There are several other Visionarry's either in production or sailing. Not sure what the count is but it seems like there are three Visionarry's on the water and several other builds in various states of completion.
3. I like the lines. There's something to be said for the sailing performance of a boat being proportional to the beauty of her lines. I think these lines are lovely..
4. The guys at Harryproa are on their game. Rob (Designer) has been answering 100's of questions for the past year and Mark (builder / draftsman) has been gracefully answering boatbuilding questions during the past month or so. This doesn't feel like a one night stand. They are passionate about their proas. I'm very clear about being an amateur boatbuilder and having them there for back-up is a good thing.
5. Plans are in good order. Being an amateur at this I didn't want to rely on years of experience to determine the best lay-up schedule. The plans I've received to date had about the right amount of detail. Additionally, cutting files are available. A few of the designers I spoke with regarding cats wanted to double the cost of the plans if .dxf's were included for CNC routing. This blew my mind since the cost of a .dxf must be significantly less than a full size print. The concern was that I would use the .dxf's (2D files) to reverse engineer their boat. A bit of paranoia out there perhaps. Perhaps there's more to this.
That's why we chose a Harryproa. Mercifully Rob has written a lengthy bit about the world of proas through a designers eyes. Check out his article on proas.
Are there things about building a proa that make us nervous. ABSOLUTELY. With any design there are concerns. With this even more. Specifically, the design does not have hundreds of thouands of sea miles under her bottom. Two of our criteria were "Robust Design" and "Ability to ride out a gale with ease." Neither of these have yet been proven. We felt pretty good about the boats ability to ride out a gale since if I were to choose any type of platform to heave to in or lie-bare hulled in it would be square raft 1/2 mile on each side. The profile of a proa fits this pretty well. I imagine getting her lined up with a drogue or an anchor might be tricky but once there I can't imagine a more comfortable platform. Adding to idea of a raft is the ability to lift the proas rudders taking away her "tripping point".
This leaves robustness. My biggest concern to date is the mounting of the rudders. It's a bit of a complex problem with a design that needs to allows the rudders to rotate through 270 degrees, lift in the Z-axis and rotate about a pivot point in the event something is struck. This just seems to be an area that will become robust from some hard knocks (ocean passages) and clever design. Perhaps the design is there already, but we'll have to wait and see.
One final areas that folks have asked me about is relatively small accomocdation space. If I were comparing a 60' proa to a 60' catamaran my guess is that the cat would have 3x the interior space. Three times the area to add heads, electrical, plumbing, bunks and electronics. 3x the space to spend money. We're hoping to have the right amount of acomodation for our need. No more and no less. Once couple cruising with the occassional visitor (that means you Dave and Reza). The weather hull is 33' long and appears to have the same accomodations as a 42' monohull or a 36' catamaran. That's about right for us. There's an interesting link at the Wingo site which overlays a catamaran with a proa.
That's about it. We'll throw a bit into the mix about our rig decision and build method decision later on.
Monday, November 06, 2006
The process of going from the idea of building a boat to purchasing the plans took about one year. As I mentioned moving from
I remember googling 'catamaran' and 'boat building' and checked a few of the sites lsited. The site that got me thinking that building a boat was different today than 15 years ago when I was involved in several Star boat builds was seeing Derek Kelsalls site and the flat panel construction. This planted the seed that a one-off catamaran was something that could be accomplished by an amateur boat builder with some composite experience. My previous exposure to boatbuilding included lofting which was something I didn't want to deal with. However, modern day surface software seems to have all but eliminated the absolute need for lofting for the amateur boatbuilder.
Further re-enforcing the notion of "I can do this" was reading through several detailed photo journals recording different peoples builds. Going step-by-step through other peoples projects fortified my intent to build a boat.
The search for a set of plans for our coconut highway crusier (between lats 20N and 20S) was underway November 1, 2005.
With that we developed several criteria to help in our search process.. They were important in the following order..
- Total build cost < $100,000
- Proven design - Robust
- On deck comfort - Cruising
- Ability to ride out a fresh gale
- Ease of build - Build Hours <>
- Accomodation comfort
- Resale value
With that we began the first pass search by looking into designs from Schionning, Gary Lidgard, Chirs White, Derek Kelsall, Kurt Hughes and Bob Oram. We narrowed it down to Bob Oram's 44C since it met our criteria better than the others. Bob is a bit less well known than the others in the states but has drawn up some nice lines and promotes a "keep it light and put the icemaker into the waterline" mentality. Somewhere along the line I was searching for build journals and stumbled into the Harryproa web site, saw the proa and dismissed the design as a horribly freakish experiment and continued on my way to the build journal for Blind Date which is a Visionarry built in
On another visit to the photo journal on the harry site I took a quick read of the design concepts of the proa.
TO MY SURPRISE IT SIMPLY MADE SENSE!
The things that presented the greatest strenghts in my eye were the following:
- All sailing loads concentrated in one section of leeward hull.. This makes the engineering problem quite simple as an excercise in cantilever physics.
- More LWL per dollar
- Less bridgedeck exposure to swells
- It was something unique and different
There's enough folks discussing the details of multihull structural design that are much more qualfied than I. However, the notion of trying to compress a mast through the center of a bridgedeck on a catamaran became quite silly.
These loads require a significant amount of resources in both time and cost.
As a rule of thumb we used a basis of $10USD per pound of boat and 1.5 build hours per pound of boat up to the sailing weight. This was derived from looking at several ACTUAL builds with construction methods using horizontal strip plank, vertical strip plank and flat panels using sandwich contruction without carbon in the hull lay-ups but speckled about for strength. It didn't seem to matter what build method was used. I'll hit this more in build methods.
This allowed us to literally stretch our dollars into more waterline. If there's one thing I've learned over 30 years of sailing is that nothing beats length at the water line for comfort, performance and safety. Below are a few illustrations highlighting what our budget would allow us to build. They represent comparisons between a 37' waterline cat and a 60' waterline proa.
Side profile of 60' proa versus 37' catamaran. Each with build costs less than $100k USD. A few things to note here would be waterline length and position of booms relative to water. Proa sailplan will start several feet closer to the water than catamaran reducing heeling moments.
Top-down profile of 60' proa versus 37' catamaran. Note larger tampoline space and reduced solid bridgedeck surface area. Less solid bridgedeck = less slamming. Bridgedeck slamming can be terribly unnerving in a poorly designed craft. Also notice larger beam.
Aft profile of 60' proa versus 37' catamaran. Note righting moments and heeling moments. Heeling moment for catamaran approximately 15% higher due to increased length of moment arm between heeling point and center of effort assuming similar sail areas. Righting moment for proa approximately 20% greater due to increased length in moment arm between heeling point and center of mass.
An increase in righting moment combind with a decrease in heeling moment equates to more stability. Once again, this is a very simplified approach to viewing these concepts and there are numerous analysis covering the topic.
More to follow in Part II
Sunday, November 05, 2006
Saturday, November 04, 2006
Leeward Hull: 60 feet
Windward Hull: 33 feet
Beam: 27 feet
Sailing Weight: ~5,000 pounds
Payload: ~4,000 pounds
Draft: 1'5" to 8'2"
Righting Moment: 15 ton-meters
Sail Area: ~860 sq ft
Designer: Rob Denney
Designer Website: www.harryproa.com
Designer E-Mail: email@example.com
I've become an enviro-whore.
In the course of three days I've gone from trying to be gentle to all things green and staying away from foam to securing the better part of a pallet of Corecell. The conscience will need some wine on this one. Found a huge batch of 5/8" CoreCell for an very good price and couldn't pass it up. The though of the core costing half as much and weighing a third of RWC was more that I could pass up.
One fine fella pointed out that perhaps the kilowatts of energy and diesel required to ship and strip cedar would offset the enviromental gains relative to foam. That's my story now and I'm sticking to it..
"First Light", our Visonarry proa is underway.
A partial set of plans we're printed yesterday for what will become "First Light", a 60' Rob Denney designed Visionarry proa. Some materials are in house. The path has been an interesting one and has brought about some fairly radical changes in the life of my wife Julie and I. I'll sum it up by saying that when we decided to build a boat less than a year ago we were living in 'no weather' Santa Barabra on a postage stamp piece of dirt and I write this sitting on a chair in Perry, Maine (or shall I say Maine-ada) overlooking the Bay of Fundy which is currently spun into a frenzy by 45 knot wind. The decision was made so we had room to build the proa. The tail has wagged the dog. We'll save this story for another day.
I've decided to blog this out since others who have done the same when building a boat describe it as therapeutic, motivational and a means to keep a healthy perspective.
There will be quite a bit of 'thinking out loud' here to go with the build process. I'll ramble on about 'Why a proa' and 'Why a Visionnary design' later. For now we'll keep it to the boat instead of our personal adventure.
Here's what were looking at today in terms of build materials and process.
Hulls: E-glass and epoxy over strip planked red western cedar using male molds.
Bulkheads: Vacuum bagged E-glass and Epoxy over end grain balsa
Beams: Vacuum bagged carbon and epoxy over strip planked red western cedar
Foils: Carbon and Epoxy
The decision was made to stay away from the closed cell foams for several reasons. Cost being one. The other being that the by-products of the foam manufacturing process are super-toxic. I have no delusions that the build will be 'less-than-green' but we've decided to draw the line at foams manufactured with methylene chloride.
The shell materials (except carbon) will be purchased from Composites One.
Still working out the details as to the final rig configuration. However, at this point we are leaning towards a twin cat rig with freestanding rotating masts. Chord will be set as a balance between performance and 'fully reefed windage'. Having a sail plan which allows full control of sail-shape is important. Most of the proa rig configurations I've researched do not allow for adequate control of the sails shape. The thought of a sloppy leech or a saggy headstay is not tolerable. We may go with a wishbone set up. Still researching this. There are a few projets underway using this configuration. Hopefully their efforts will be useful in determining our final rig down the road.
Regarding outfitting: The last two cruising cats I've sailed have been outfitted to the the point of silliness. The Norseman /
I won't even go into what was on the Gunboat. Wow..
Our goal is to keep things a bit more simple, less expensive and enjoy the more traditional aspects of cruising versus a 7.1 surround sound DVD entertainment center. Hopefully we'll be cruising with the
And so it begins......
Wednesday, November 01, 2006
Wingo Website with Russ Browns Pacific Proa
The Proa File
Cruising Proa Concepts
OTHER SWEET BUILD SITES
Henny's F-39 project using resin infusion in the Netherlands
Couple building a Schionning in Australia.. Great audio!!
Oram 44C under build in Australia
OTHER STUFF OF INTEREST
Bob Oram Catamaran Design - If you must build a cat, check these out!