Tuesday, December 16, 2008
step 1: cut your mast/hull/wings up into little pieces
step 2: place in luggage
step 3: reassemble at desired glabal destination.*
*nick flutter takes no responsibility for any complications arrising from above process
Saturday, December 13, 2008
Sunday, November 16, 2008
Tuesday, November 11, 2008
been sailing a few times, but mainly been in front of the computer evolving into one of those hunched, pale, widescreen-format-eyed little creatures (from the future).
anyway the whole time i was studying i was sidetracked with a stack of new ideas for a moth, and im pretty sure ill be building something over the summer "break". The lines are from Doug Culnane's Lord Flasheart, designed in collaboration with Adam May. (cheers doug, looks great)
Flasheart is available for home builders like myself to have a crack at, so in the interests of total tansparency ill be chucking everything up here form design to eventual completion. that puts the pressure on to not fuck it up i suppose.
construction will hopefully be by female mould, cut from high density foam using a 3d router. dont know how much that will cost yet, but the plan B is a hot wire and ply plug. the boat will be built in 2 halves, vacuum moulded etc etc. the aim is to keep construction extra simple and quick so that the thing isnt still half finished in a year or 2. kinda defeats the purpose. 10kg for the hull will be acceptable, but i will of course be going for lighter. as this is my first go i want to make sure it holds together.
what the wind 'sees'
there are a couple of odd ideas in this. this is only the first iteration, i might do a few versions with different configurations to get a feel for what will work best, be lightest and cheapest. I'd love some feedback on what you think will work and what wont. at this stage i think its better to get a bit of consensus on things. The main decisions i've made with this one:
- Foredeck, wavepiercing bow - The stem is even shorter than Flasheart, which is on the short side as it is. im hoping that the bow in this configuration will go further underwater without digging in, and use the buoyancy around the mast base to pop back up. i find that most of my stacks at the moment are due to the drag of the foredeck, tramps and ropes stopping the boat, rather than the pitch.
- Kingpost, Recessed foil wingbars - The foil shapes are mainly there to reduce fricion when the hull does go under a wave, though they should reduce windage a bit too. circles are terrible in terms of drag and im avoiding them as much as i can. The kingpost is cantillevered from the keel, so there is no need for a forward support, that adds areodynamic and hydrodynamic drag. ill make a bladder mould for the kingpost, so i can cantrol the fibre orientation and reinforcement.
- Wings - Raised up and out of the way of everything. the freeboard is slightly lower than flasheart aft, (50mm) the wings are slightly higher. They are airfol shaped, only because i think it would actually reduce drag a bit. it opens up a big gap between the tramp and hull which will reduce windage.
- Flare - I altered the bow of Flasheart a bit to include a 10 - 15mm deep step. for lift.
- Centreboard is 100mm further forward that Doug had it - his was in the same place as my current boat, on which mast is 200mm further aft. what is a standard dimension these days from transom to front of centreboard case? assuming 8 degree strut rake.
- the outside wing bar continues aft of the back wing bar. the joint is easier, and you reduce tramp area, while still having somewhere to sit. and if i find the back bar is too far forward, i dont have to buy new outer bars.
- There is only one internal bulkhead at the centreboard case, which is pretty small. (divides in 2 as per rules) some diagonal reinforcing will be built into the hull laminate.
anyway the only things i am sure about at this stage are the general freeboard, and the step in the chine.. foredeck could come up, aft deck could be convex (better for 3d router). wings could atach to the hull (i feel it may be better to have something solid to stand on, rather than just tramp, though this means reinforcing the deck a bit?)
anyway ill keep plugging away, please email me if you have any ideas
Monday, October 13, 2008
Monday, August 25, 2008
Saturday, August 2, 2008
had a go on Rod's bladerider, and doesn't that make it obvious that my boat is underperforming! you just sheet on, point it, it pops up to the right height and accellerates endlessly, without spontaneously launching out of the water, tipping over sideways or sinking back down. i think i hit over 20 on his velocitek, though it may have been lying. the linkages on his boat were working overtime, while mine were kinda stopped, lethargic. it was interesting to see my boat being sailed well by someone else also, and i know a couple of things. it can go quick upwind when sailed propperly, though probably not in less than 15 kts. It looks really bulky when foiling compared to all the other boats. its like the fat kid.
resolve to put it on a diet. failing that a new hull/wings.
new bladerider sail is an improvment, needs slight luff adjustment.
Wednesday, July 16, 2008
Basically when i sit at the back of the boat and try and launch, i can get up to about 7 degrees angle of attack on the centreboard foil as the bow lifts up, and my boat's fat ass drags in the water. lifting off like this the wand starts moving the flap up, as the front of the boat starts to clear of the surface. in this configuration, with the flap down say 5 degrees out of 20, the centreboard Cl is 1.57 and Cd is 0.0193
If on the other hand i was to sit really far forward and keep the nose buried, i could keep the flap at say 15 degrees down, at the same stage of takeoff. in this configuration the centreboard angle of attack is 0 degrees, but with the extra flap deflection im still getting a Cl of 1.54 and a Cd of 0.0156. so this is better, same lift for about 80 to 85% of the drag. ill try it out on the weekend.
also i ripped off my crappy wand. finally. i laid up some new bits tonight that will allow me to adjust everything about the wand, and to use carbon rod and tube of varying stiffness and size. I have a choice of two wands to start with - a straight stiff one with flexible tip and a kinked, stiff one like the old prowlers, with a flexible tip as well. ill try both on saturday weather permitting. The aim of all this is to keep the flap at full deflection while the bow is within a foot of the water. the winning wand gets glory. and to stay on the boat. it is possible that they will both lose, in which case shame will be brought apon their families. and they both also die.
Saturday, July 12, 2008
The linkages work much better, and the rudder adjutment in particular is a massive step up from what i had. the wand vibrates when going slow, which is annoying, so ill take to it with the grinder and make it flatter on one side. also thinking about a flat surface on the end, so that not as much of it drags in the water.
i need a new sail.
im not quite happy with the angle of the centreboard. i noticed that i had the rudder trimmed back, flap up about 5 degrees, to the point where half the time it was actually pulling the transom down; you could see because the top gudgeon was touching the top of the gantry, rather than there being a small gap. seems to me the rudder foil could be smaller. before i go cutting stuf im going to make an F-box of sorts, a contraption that lets me adjust the rake fo the centreboard over about 5 degrees on the fly. also i want to put a small bulb at the T joint of the centreboard, to hide a wad of carbon uni that i will wrap around the leading edge at the T. the crack didnt get any bigger, but im not going to risk breaking this foil. so there's 2 or 3 projects to keep me busy(er).
Saturday, July 5, 2008
Sunday, April 20, 2008
2. at least i missed them.
Friday, April 18, 2008
Thursday, April 17, 2008
Wednesday, April 16, 2008
The ball joints on the other hand were a complete failure, i tested them with a good solid yank and they came off. will swage copper ones tomorrow. also got the rudder gudgeons on. 6 jobs to go.
Tuesday, April 15, 2008
im bagging everything form now on! something to bag, ill bag it. fibreglass, oranges... small animals... lock up your pets!
Sunday, April 13, 2008
a few cuts here and a few holes there, a bit of sanding.
the rudder is strengthened almost to the centreboard spec, it will hopefully be strong enough. (in its defence it is 2/3 the area... your honour.) i made it shorter beneath the boat so its foil travels 60mm above the line of the centreboard foil, and out of its downwash. there will be a reduction of the torque on the gantry from steering and foiling high, and also it will help the foil ventilate in a crash and thus not snap. we hope. and since there is not so much rudder in the water when foiling high, it will reduce my tendency to jam the tiller towards me to bear off before crashing, as that little bad habbit was breaking things... well reduce it by making it pretty much ineffective. hopefully my new reduced friction centreboard flap will help in that respect too.
Now for the gantry. The QLD moth states and my deadline are fast approaching (we're inside a week) The gantry should take 3 or 4 days to put together so i may even be able to rig the boat before the regatta. ha! as if. I bought a vacuum pump off ebay today for $160 bucks, which i think was an ok buy, and its in brisbane too so ill pick it up tomorrow, get some tacky tape on monday and be sucking on monday night. in the mean time i need a jig to get the angles of the tubes right and get them glued/carboned together.
other than that i need to fix the hole in the boat (i bought a clear bulkhead cap for it, stuck it on, but it was a tight fit so when i tested it after the sikaflex had dried, i realised it was squashed and the cap wouldnt screw in.) (try again timmy. Timmah!) I need to get my welding bloke to weld my little stainless gudgeon for the gantry lower attachment, i need to get a batten for my sail, and i need to make those fiddly little ball joints that attach the rods to the flaps.
and that is all.
Sunday, April 6, 2008
Anyway i got the bell cranks designed and cut out. All the linkage bits i pretty much thought up as i went along, though i had a vague idea of what i wanted; they definitely had to be bigger than before, and i wanted to minimise friction and slack as much as possible. The little carbon forks on the fibreglass rods I think were a good idea, easy to make, we will see whether they hold together or not. they look pretty tough anyway. My little stainlless threaded fork is an M5 turnbuckle body that i cut up, and took about 5 minutes to make with the grinder. The thread is done for you its great.
I also took the opportunity to finish off the cams and do the wand as well. The centreboard system is pretty done save a bit of bog and the ball joint on the flap. Im waiting until I've done the gantry before i cut the rudder to length and put its linkages together.
I checked the centreboad foil angle of attack today too (first time in the boat) and its what i wanted (good management more than anything i think!) between +1.5 and +1.8 degrees on roungh calculations. Much more than that and you start paying drag penalties, but form memory up to about that range you only gain 1% or 2% Cd but significant Cl.
Also i went to pick up the carbon tube I got from CST for the gantry from the post office as i was out when the courier rocked up (as is always the case) but the post office is apparently shut on the weekends??? wtf? how backward are we! I now get the whole '5 working days' thing. There must be an easier way to get something from one person to another... in this day and age.
Tuesday, April 1, 2008
Monday, March 31, 2008
- First of all the T joint has no foam in it at all, just glue (sp microfibres). Last time it was foam and bog (Q-cells) with carbon strands in it, that wasnt enough.
- There is some diagonal carbon along the front and back inside edges in the areas of high shear stress - i just chuked it in there with a big glob of glue in the middle; the idea is that when the mould squeezes together it gets pushed to the places the glue is oozing out.
- you can see in the photo I integrated my carbon T-piece into the bottom surface, that pushed straight up into the foil and is encased in glue. hopefully there is no way in the world it will separate from the bottom skin, or pull out of the strut.
- Lastly i plan to further tie the leading and trailng edges of the foil together around the T joint area and the exit area by making carbon 'wet bolts', at about 30-50mm centres for about 250 - 300mm, to join the top and bottom surfaces. ill put photos of them up when i do them.
Also i cut my finger twice in the same spot with the grinder. first time with the cutting disk then again with a sandpaper disk. the second time it went straight through my nice fresh band-aid. I put a heavy glove on after that. When you wear a glove you might as well have a bit of wood for a hand.
Friday, March 28, 2008
Came to the realisation that i should have wet out the flap hinge in position in the mould, and stuck the plastic spacer strip on it there too. now i have to glue it in with PVA, and glue the spacer onto it. hopefully the mould type PVA will stick it. I wasnt organised yesterday to do that, so it never would have happened, but for next time...
Also completed step 2 of the cams, ill see how they come out tomorrow. ill bake them with the foil so ill post a photo of the finished product. i think they will be ok.
The carbon is now cut out too. its such a shame to cut up those big perfect sheets, but you gotta grit your teeth and do it. and hope you get it right. the hull became a pretty good bench, at 21kg bare, i think it is almost better as a bench than as a hull. anyway thats a couple of projects down the track. Oh also i cut a hole in the hull that i really shouldnt have cut... more on that later.
Finally i just want put it out there and say thanks to Andrew and Scott at CG composites for being so helpful with the resin and reinforcements, bog, glue, and peel ply etc. and to Mel and Miller and David at Glascraft Marine for putting up with my crap. From those two places i've been able to get 90% of the materials I need to keep this project going, and some good sound (and patient) advice, which has probably been the diference between a semi success (so far) and a complete cock-up. also Bretts/Bunnings you're both wankers, though 'Tube Sales' at Yatala i like.
Wednesday, March 26, 2008
also laid up the T piece to tie the bottom plate of the foil into the T joint, and also the tang to attach the gantry to the transom (in the same mould.) mould looked cool i took a photo. The T piece i will drill some holes in, to make sure it bonds well to the bottom plate, also i will put a couple of layers of carbon over the top of it.
Did the hinge as well, had an interesting incident with the leftovers of my hardener-heavy resin (to make it a bit more flexible than normal) started smoking and actually boiled and set in the tin at the same time. must have been hot today.