Home built single hander project

[joz]

As I have posted this under Boat design for benmww I believe that There is a boat that might suit your needs its called Lake Burley Griffin designed by Glen Seeley if you can get your hands on Australian Amateur Boat Builder Ed 56 Jan-Mar 07 on page 87-88 it has it and also its a decanting keel dinghy and made from plywood as well.

[benmww]

how do they plane with the canoe stern

[gggGuest]

Originally Posted by benmww

how do they plane with the canoe stern

The same as any other boat. What the last foot of the boat is doing isn't that important compared to what's going on further forward where the majority of the lift is going on.

[PI Design]

Originally Posted by gggGuest

The same as any other boat. What the last foot of the boat is doing isn't that important compared to what's going on further forward where the majority of the lift is going on.

That depends on how fast your going. As you speed up, the WSA by necessity decreases until only the back is in the water. Admittedly, even an IC is unlikley to go fast enough to have only the last foot in the water though.

[Andy P]

Originally Posted by benmww

how do they plane with the canoe stern

The same way that sailboards with pintail sterns plane.... only they can plane at 40 knots - so it is possible.

[bistros]

Thanks for all the feedback so far, folks!

I've had an offer by an experienced designer in this forum to develop hull plans for my project as part of their design portfolio. If the project works out, I'll let everyone know and publish a build blog documenting the process. The designer will retain rights to the design, and they have indicated that the results will be available for future builders for a nominal designer's fee.

I'm going to take them up on thier offer, as they have welcomed my ideas and will consider them (if deemed worthwhile) as part of the final design. I am quite excited about the potential of the project and have a lot more confidence about the chances for success.

Thanks to all that have responded, and keep the ideas coming!

I guess I've got to start shopping around for WRC stock, and get a good strongback built. I'm going to be milling the strips myself to save money, and I hope to do enough inventory to get a sea kayak for my wife built as well.

It'll be time to start to mess the garage soon. I think a low buck dust collection system is in order before the router starts up.

[Steve Clark]

I'm not sure we have actually mat, but I have been to Skiff Grand Prix for the past 3 years, and with ICs for the last 2. So you have seen us at play.
Alistair Boyle has a building jig in Ottawa if you want to coppy his boat, or if you want to be more origional, you can play the development front.
Several optione exist, if you want to converse further you can send me a PM and we can get on with something.
New IC taking shape ebjnen as we speak.
SHC

[tuks]

How about an update on this project? Can you tell us who the designer is, I am interested in a boat like this.

[bistros]

The original designer that offered to help went quiet and never responded to my ping attempts. Like most of us he probably got busy.

I did end up working with a local naval architect, Eric McNicholl (http://www.veloxdesign.net) who was updating a previous design. The Mark II Falco is basically a one-man I-14 type trainer with a cut down 5o5 main and an asymmetric spinnaker. The hull is built and we're getting the rigging assembled right now - the hull was first trialled with a sailboard rig from another boat.

The new rig is a slightly cut down Proctor D mast, a large diameter carbon boom and a cut down 5o5 main. It should be on the water within a week or two. We've got to add the forestay attachment point carbon re-inforcement and some structured deck ribbing to solidify things a little.

The boat as built weighed 74 pounds for the complete hull, and with the added structure and reinforcement it should still be around 80 pounds. All up the boat should weight about 125 pounds rigged and ready to sail.

14' LWL, construction of cedar strips and Okume plywood panels along with Okume bulkheads and cedar sheer clamps and stringers. Preliminary testing with the sailboard rig was excellent - balanced and quick.

I'll post an update once we get the new rig sorted out enough to have an opinion.

[bistros]

The preliminary on the water testing has gone extremely well, considering the old Hood 505 main we used. The boat is very fast, planes in 6-7 knots wind both upwind and down. We haven't sailed it in over 10-15 knots yet, so it will probably be overpowered. At my weight (210) I have been out on the trap only at the high end of the testing wind scale. Eric ( the designer at 135) traps every time he is out.

I've been sailing the boat on skiff race nights and it moves well compared to other boats. I think it will certainly be competitive with the Musto Performance Skiff and SwiftSolo (which were my design goals). Now we've got to get a proper main made.

The asymmetrical spinnaker is smaller than it could be - it was intended to have the halyard at the top of the forestay, but the 505 (old style smaller) spin halyard is about 2 feet higher than the forestay - hence the first spinnaker could be significantly larger than we had made - oh well, next year I'll get another made to fit the (new, larger) 505 upper spinnaker halyard. That will probably almost double the spinnaker size.

The boat weighed 74 pounds before we started rigging - the complete boat with all rigging, sails etc. weighs 120 pounds.

The old Hood 505 main was surprisingly okay - it was not too much sail. I though that 12 sq meters would be excessive but it was not - we did not cut the sail down at all. I can imagine what this will be like with a proper new sail made to fit the mast, and with a higher aspect ratio than the 505 main. The boom is quite low right now, and it is also longer than the cockpit - we raked the mast forward somewhat to compensate for the lower aspect ratio main. We cut about six inches off the bottom of the 505 Proctor D mast (removing vang-induced metal fatigue/cracking from use in a 505).

I decided to go with a dual tiller extension setup - and my first prototypes were from bamboo - which worked reasonably well.

We really need to get the kick rails and sheer clamp covered in non-slip - the boat is slipperier than a greased pig right now. We expect to go to paint in the next two to three weeks.

Once the boat looks better (currently just epoxy and fairing compound) I'll post pictures if people are interested.

--
Bill

Congratulations-sounds terrific! Pictures would be great when you're ready...

[tuks]

Bistros, It sounds awesome. Is this the boat on the "ottawa Skiff & cats grand prix" thread on anarchy?

[bistros]

Yes. During OSGP we were doing preliminary testing with a unstayed sailboard rig. The asymmetrical spinnaker was not rigged, and of course no trapeze.

The build was actually incredibly fast - we went from CAD files to CNC cut stations and completed hull in about three and a half weeks. The build was somewhat experimental for Eric - we wanted to combine a complex strip planked hull bottom section with Okume plywood panels on the sides, decks and bulkheads. There are cedar stringers and sheer clamp as well. Basically, this design was optimized to provide strength where necessary, light weight where possible and the right materials for each.

The outside of the hull was covered in 6oz S-glass and West System epoxy after initial fairing. The inside was epoxied and all the bulkheads filleted. Where necessary, there were stringers and re-enforcements added before the false bottom deck was added. The internal deck has got structured triangular beams on top which provide both stiffness and kick rails for trapeze usage. The beams are epoxied & filleted to the flat deck surface - they weigh almost nothing, but are incredibly strong.

We are lucky in Ottawa - we've got a very active skiff fleet and some great local talent. Phil's Foils cut the stations for us, and they also machined the foil from a composite blank we provided. The foil was made from cedar and carbon composite, then covered in 6oz glass. Testing as proven the foil is a little too flexible in it's first iteration (for my weight), so we'll be adding another layer of carbon/kevlar where needed and then glass to stiffen it somewhat. The first edition was around three pounds - after mods it should still be under five.

As this boat was experimental, we tried where possible to keep the costs low - using existing and available rigging. The Proctor D mast was purchased from "Tiny", a local 505 guy, as was much of the standing rigging. We figured that once the 505 fleet approves carbon spars there will be lots of Proctor D's available for this type of boat. The boom was an I-14 large diameter carbon tube. The spinnaker pole is a section of tapered aluminum sailboard mast. The pole launcher tube is a 2 inch PVC pipe. I did the first tiller extensions from a carbon pair of skate skiing cross country poles (not cheap!), and then built a set from bamboo ($0.75 each).

The main was a donation from another local 505 sailor - it is of 70's vintage, but it works. The intent is to have a large roach flat-top high aspect ratio main made that is angled up somewhat at the boom, like the Musto. I sail a Laser 5000 twin wire skiff and I'm used to walking (running!) from side to side during tacks - the Falco is too small under the boom right now for that, and I want mobility to be good. I'm too old to tack/gybe this boat like a Contender/Finn, and the skiff speed doesn't leave time for under-boom contortions and gymnastics. Slowing down leads to excessive swimming and you've got to keep the pressure down.

--
Bill

[tuks]

Sounds great, keep us informed. Don't forget the pictures!!!

[bistros]

Originally Posted by tuks

Sounds great, keep us informed. Don't forget the pictures!!!

Another update:

I've now had the boat out a few times in different conditions, and have formed some better opinions.

The old 505 main's condition is quite baggy and blown out. It is quite hard to get it shaped properly, and overall performance really suffers. The sooner we get a proper main on the boat, the better. You really notice the sail shape problems going uphill. I was able to observe the boat when sailed by another person in decent wind and the thing really needs a LOT of vang and Cunningham. I think the adjustable shrouds need to be added sooner, rather than later. Given the relatively simple preliminary rigging, controlling mast bend and sail shape will become a real priority. I've been thinking about controlling mast pre-bend with shims at the deck/mast opening like 505's used to. I do not want to have to implement an up/down mast ram if I can help it.

The boat with the current 505 main is a nasty bitch to right, even after blowing off the vang. This is exacerbated by the understrength daggerboard. I'm tempted to put a plastic "training wheels" jug on the top of the mast till I get better at righting the boat. I'd like to know how much of the problem is due to the current (uncut) 505 main and it's shape and condition.

We've got to strengthen the daggerboard quite a bit to make righting the boat easier (and eliminate the very real potential for breaking the board). The spinnaker sheets make decent righting lines without extra holes or rigging.

The current daggerboard seems to be on the small side to me, but it hasn't really been faired/sanded yet, and I do not want to pre-judge it till the trial is fair. The boat is not a fast tacker by any stretch - and the small board may be an issue. I knew we were compromising the tactical nature of the boat somewhat for speed, so the reduced rocker and slow tacking was expected. I expect this is more a software problem to be solved over time than a hardware problem.

The boat needs reinforcement in places that are going to get abused (or used hard) in normal sailing. The 3mm Okume is not sufficient for the side deck area - although braced well, one test-sailor drove a trap hook through the side deck re-entering the boat after a capsize. He also split open a seam between the false bottom deck and the hull running across the boat during a righting attempt and placing his foot hard on the hull. It would be easy to blame the hard testing for the damage, but I think the boat needs strategic strengthening. This all took place during an outing in winds of 15kph (to 25+ in gusts). Basically, full time trapping wind. I sailed the boat in the same conditions with much less trouble (but perhaps my previous sails had made me a little better). The other person has quite a spectacular on the wire "around the front / down the mine" capsize that was more fun to watch than experience! Foot loops are needed badly as is the non-slip.

The Proctor D mast weighed in at 16-17 pounds after shortening it about six inches. This is a very heavy 16 pounds high up when on such a light boat. You feel the mast mass as a major factor in stability. The boat is not stable at rest, and is not easy to rig on the water at all. I think a carbon mast will become critical in future development of the boat. Keeping this boat vertical and flat is paramount!

The boar is currently rigged with a rear bridle and center sheeting with a ratchet block/cam cleat mounted on the centerline after the daggerboard slot. What a pain in the ass! The main sheet was a serious hazard/problem hanging down off the boom during maneuvers (later fixed by adding loops). Cleating off the deck is a pain (not easy from the wire) and reduces mobility - I'll be putting the cleats up on a head knocker plate off the boom immediately. I'll prototype in aluminum plate and probably make the final in something lighter.

The main sheet really needs to be safely attached to the helmsman so it can be at hand - dropping a sheet on this boat can quickly be a major problem! The best system I've seen is adding a loop Velcro handle to the sheet that tags to the hook pile on the trap harness - easily removed, but it keeps the sheet at hand.

The bamboo tiller extensions are too big (easily fixed), heavy feeling (not easily fixed). The SwiftSolo style stretch cord between the extensions (attached to the tiller in the center) doesn't work as well as I hoped. The unused extension often drags behind the boat once it touches the water on the leeward side of the boat. I'm going to look at a local Vector that handles things differently (as well as the local 49ers). Perhaps running the shock cord like trap harness retainers will work better. I tried the lightweight carbon ski poles briefly (before the UJ tiller attachment failed due to bad implementation issues) and they seemed a lot easier to handle than the bamboo - much lighter and they felt a lot better. A little refinement is needed.

I'm kind of using this forum as a development blog - please do not interpret my raw comments as negative, but rather as unfiltered documentation.

I'm very happy with the progress to date and can not wait to get the boat to paint.

--
Bill S.