The States

Im not actually on the same lap as matt...

1. out of control approaching the bottom mark. i was on the same lap as the scows.

2. at least i missed them.

well I finised two races, and in one of them i beat another boat.

Had a couple of teething problems as you do when your that unprepared at a regatta.

Saturday was a bit of a write-off, as it was squalling through at 20-30kts as predicted. there was one boat in a fleet of 11 which did not sustain any damage, and that was Matt with his bladerider. He sailed the boat pretty damn well for the conditions. The sheer variety of damage seen on the rigging lawn after racing was abandoned was impressive even for a moth regatta. I lost my rig, and in the process busted a panel in my pretty shagged sail. (fixed with gaffa tape) The foils were fine, but they were probably to blame for the whole 'losing the rig' caper in the first place.

I have somehow managed to stuff up the angle of atack of the centreboard, i think. There isn't enough +ve angle, which meant i wasn't getting up and foiling at the kind of low speeds i should be able to. I will fix it by increasing its forward rake, which in the long run isn't a bad thing. This means i need to modify my centreboard case thing.

The rudder adjustment systems is shit. needs a better sollution.

Both ball joints failed on saturday, and though i tried to fix them with 5 minute epoxy, they were too loaded up and snapped again within minutes. So i sailed Sunday with no flaps at all, and it was predictably hard to foil and hairy once up. I have a new 'bladerider inspired' sollution, which should work or at least look a bit pro. Means ill have to go back to stainless rod for pushrods instead of fibreglass. no big deal.

Anyway, for the next month or so I've got a bit on at uni, probably not much will happen on the boat. After that ill sort out a new mast and sail, and get to work on the few things to tune before i go sailing agian.

race ready but no sail today

its 30kts from the SE today. had a couple of odd jobs to do, could have dropped the boat down to the coast today and got a quick sail in but i decided it wasnt worth it. probably better to get some uni work done. Rigged it up as best as i could in the garage to make sure the flaps worked etc. they did, here are a couple of images.

Done and dusted

Dusted figuratively not literally. The dust will blow off on the highway tomorrow.

Missing one tripple block on the cunningham, ill have to get that on the way. The forecast is for breeze, 20-30kts, i am dobtful whether the boat will last the weekend and more doubtful about the sail. (now largely just gaffa tape) However i haven't fixed the low-rider rudder so foiling it is, and theres no backing out. The boat is literally rough aroud the edges, and obviously underprepared, but pending the success of the ball joints on the flaps (curing now) i'd say all the systems are go. [im liking this motif of using cliches in their original context] The adjustable gantry looks pretty good, though i realised why everyone else's have only one lower strut and not two; there needs to be some flex in the joint between the strut and the bottom gudgeon to facilitate easy adjustment. anyway its fine for now, hopefully i've got the angles right and i wont need to adjust it. The cams seem to work in the sail, ill wait and see on that one as well. i have a spare just in case.

gantry done pending 12 hours @ 80deg.

The release went well from the mould, by my standards. (lucky i didnt spend too much time on the mould.) The vacuum finish is impressive, the part is actually lighter than my previous gantry and 200mm longer. and intact. yay. at this point i declare the design to be good, and the construction to be good. lets see how we feel after a couple of sails...

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.

sucker!

My $150 ebay vacuum pump came through with the goods!
im bagging everything form now on! something to bag, ill bag it. fibreglass, oranges... small animals... lock up your pets!

yeh anyway so i had a couple of small issues getting it to work, seeing as it was my first go, and the job was quite complex. i think that box was the most complex thing i've ever laid up; it had lots of different ingredients and was awkward to get your hand into. My main problem with the vacuum was in the spikiness of the mould. You wouldn’t think so hey. The spikes, nails, bits of glue/bog etc made a couple of little holes in the bag, and i tried patching them up with tackytape. Didn’t work, so i got a whole new bag (garden strength garbage bag) and put the whole mould and bag in that. Taped it up. sweet.

Carboned up the other bit of the gantry, the two tubes. Also stuck some little globs of glue in the exact right places on the control rods in the foils to serve as the balls in my flap ball joints. Got the stainless T piece welded also, thanks to Rod at Astro Metal for being a good bloke.

8 things to go on the list.

working parts

tried out the vacuum today, seems to work. will have a more definitive answer tomorrow when i 'bag' the gantry.

otherwise on track to be done for thursday night hopefully for a sail on friday!

rigged up my flap adjustment systems, the rudder system is a bit questionable. not sure if i have gone forwards or backwards with that one. (the extra bits on the rudder are the remains of my old system; im not prepared to write that one off just yet.

The centreboard control mechanism needs a taller mounting block to attach the cable to the cockpit floor, and i think ill bodgey something up there cos i already have the gear to stick a rod through the boat bladerider style. just not the time. there is more friction than id like in that system but at least not too much slack.

Overall im pretty happy with the new main foil, which is now completely done sans ball joint. The top skin hinge is neat, and flexes really well, and the gap closes up completely when the flap is at full deflection. I have an issue with some .5mm lips on the top surface around the hinge, due to my not laying the kevlar up in the mould, but tacking it in later. not top priority though. if it survives one regatta i might think about fixing those.

pretty hectic day tomorrow of uni and gantry, with a few vacuum bits still to get. we'll see if i cant stuff up my schedule.

a sigh of relief for the foils are done...

pretty much anyway.
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.

Bell Cranks and linkages

Knocked off a few niggling little jobs today. It's been hard to work around uni and last night was my first good sleep all week (3am - 11am). will be no such luxury tonight, this counts as procrastinating and i have a meeting at 1pm tomorrow (sunday!) and about form now till then worth of exploded axonometric diagram to do...

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.

It had a baby and then the baby had a baby.

What i am of course referring to is what is by now one of my favourite things to do; pulling a mould of something out of the oven and then pulling some nice looking carbon bit out of the mould. and intending to wait until it is cool to open the mould but not having the patience and getting burnt. and in this case dropping half the mould on my toe.

cool. so randemnity aside, i have, for the most part, a foil. the flap works after a bit of cracking of stray bog, and the recess i made in the mould (at the T joint for the flap) came out perfectly.

The oven sat on 75-80 degrees for 24 hours, last time it was summer and it all got a bit hotter, more like a solid 80-85. and the resin loves that, so consequently i haven't got the tesnile strength in the resin quite as good. and it has a different, dull pitch when you knock it. but its still ok. that coupled with the better lay-up and a couple of other dirty tricks i have up my sleeve (rubs hands together) should hopefully make this one not break.

so also the top hinge worked well. The kevlar is 2 layers of 75g, one at 45 degrees, so its pretty much exactly as flexible/stiff as it needs to be. as you can see the gap closes up pretty much prefectly when its fully deflected, which will be fine, as id say it will create turbulant bubble at the kink and be pretty efficient. with the flap up at high speed the separation point on the bottom surface is well forward of the gap, so no real drag there either I imagine. Thats my (probably ill informed) justification anyway. wait and see.

sandwiched

laid up all the carbon on friday, laminated the 3 bits together today. went fine, im happy with the amount of material, though this time i didn't reinforce the skin so much at the exit point and at the T-Joint. There was still ample weight of carbon in those areas but, the weakness last time was in how i dealt with the shear loadings.

Anyway i've improved the sheer resistance in a couple of ways, the result of which will hopefully be a long as prosporous, successful life for the foil: (carreer as a banker, hot wife and a couple of kids, townhouse in central sydney, big boat etc.)

• 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.

waxed and ready

I think this is turning into a way for me to summarise my days work, so i can swich off and so it doesnt keep me up half the night planning anf recapping. and mistyping.

anyway i thought id get the foil laid up today, but kinda ran out of time and oomph.

made a last minute alteration to the mould; something id been planning to do but forgot about. its made out of some thin acrylic filled with araldite/Q-cells, took 5 minutes to set. stoked. i wanted it to be quick as at that point i still thought id be putting some carbon down over it tonight.

Its there to create the gap between the foil and the flap, so i dont have to cut a gap and thus stuf up the carbon skin. also last time i had to reinforce the centre of the flap from the outside after id made the cut, this time i can do it from the inside and it will all be flush. saved some time. its a bit rough cos i didnt sand it at all, just chucked wax straight on, but itll do. may have to bog the foil slightly (probably will anyway, as the fibres wont want to bend around, and i dont have a vacuum set up yet.)

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.

gantry mould, cams, foil prep

Unrolled the sail today and noticed that its not only completely shagged, but i was missing 4 out of 5 cams. i think i gave them to emo in return for partly busting his sail. so anyway i've half finished a new set of 5 out of carbon, i dont think there will be any weight saved rather its just easier than finding where to buy them. when theyre done ill decide whether theyre good or not. i hope they dont snap in a race. just one more thing to go wrong.

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.

construction commences!

about a year late... but hey. what can you do.

hopefully it will all be done in time for the states on the 19th of april. if the new foil's maiden voyage is race 1 then i guess that constitues success. !.

The foil is designed with some sneaky new improvements, and i have re-surfaced the moulds (they are a fraction more accurate to the NACA shape now) and added and subtracted aluminim strips as appropriate. The front edge of the foil is now 10mm forward of the strut, so that the rod has more leverage on the flap. I've stuck the moulds back together like before, so that all the angles are adjustable, using longer bolts this time, and the result resembles some kind of fusion beween a smoked chedder and a jarlsberg. lots of crumbly holes. whatever, they'll get covered in wax and resin anyway.

I've also designed a new gantry, maxed out to 500mm, as the spacing between my foils is, well, close, due to the limitations of working with an existing boat. Ill make a good mould for this so that sometime down the track, if need be, i can make a good, light version with my vacuum gear that im going to buy when i get cash. Although if there is a new hull, there may as well be a new gantry. orrite so ill make a slap-up mould. or just buy vaccuum gear now.

I've sussed out a (hopefully more effective) new rudder flap adjustment system using a piece of string and a cleat and some elastic/pulleys etc. we'll see how that goes.

also my stsainless cables inside the foils are going to get replaced with some nice smooth fibreglass rod. the centreboard first, the rudder may need to wait until after the states. Ultmately there will be a bladerider style tube through the foredeck so i can do away with the friction-friendly throttle cable. and a new wand hinge mechanism.

i have my work cut out for me i guess, but im on holidays this week so ill get right into it and see if i can't get a foil laid up and a gantry laid up by next friday

to buy:

carbon.

release wax and PVA release agent

resin

fibreglass rod & end fittings

new wing tramps

some rope and pulleys

to bring us up to speed

I bought the boat from a nice bloke in the northern territory at the beginning of 06. I'd never seen it in the flesh when i picked it up from the truck depot and was all round pretty stoked with it. The bare hull weighs about 15-18kg with fittings on. The wings are carbon (fibreglass?) sailboard masts. carbon stick, sail was almost dead. The boat is rock solid though, and as a first moth and a test platform for ideas it is very satisfactory.

Tacking out of the manly boat harbour the first time was interesting. And on my second sail i broke the wings; the middle of the aft bar and the port tip of the fore bar. I didnt realise that the aft wingtips needed to be tied together. after a pretty long swim some windsurfing dudes helped me get the boat up the rock wall of the marina. repaired:

also the t foil came off the rudder, i took the opportunity of saving myself about a kilo by doing away with the old gnarled rudder box, and re'built the rudder; the old blade as a one piece arrangement with a new T-foil made out of laminated balsa and a carbon tiller and tiller extension. this made the boat much easier to control. i also raked the rig back lots, and replaced all the ropes and most of the blocks, both changes were winners. how someone managed to get it around the course with the previous setup i dont know, but i take my hat off to them.

That all went ok for a couple of sails and I started looking into hydrofoils. Then my flash looking one piece rudder snapped while bearing away one day. another hour in the water, finally picked up a tow back to the harbour, and after that hydrofoils looked like a very good option.

My first hydrofoil mould.. was a work of art, but not so much of science or engineering. we wont go there. important lessons learned.

The second moulds used a thicker NACA 6-series strut section, rather than the NACA0012. This benefited from having a more rectangular shape, and being thicker, and hence a stiffer strut. the mould could be bolted together to form the complete foil. The lay-up took 2 days per foil - all the carbon in one hit (6x400g uni, 1x200g twill on the outside and 1x300g double bias on the inside) and peel ply. Then a 200kg/m3 foam core set with a wet Q-cells bog between the carbon bits, and the whole thing was bolted together and pre cured, before being baked at 80 degrees for 24 hours. The result was precise, with a nice finish, no bubbles, and very stiff, and tense. it resinated when you knocked it, like it should.

I made an adjustable fairing for the foil to fit into my existing centreboard case - a case within a case. all the control systems were very similar to what the prowlers were running at the time. i purposely made the foils a bit long, knowing i could move the rudder gudgeons and re-drill the centreboard to shorten it if need be. first test was in the manly boat harbour in 5-10 kts, and to my surprise all 45kg of boat and 75kg of skipper went rocketing out of the water on the first puff. i foiled around for 10 minutes and called it a day. the control systems really didnt work that well, but i really didnt care at that point. stoked.

Second time out it was a bit breezy and a bit choppy on the bay. The sideways force on the long rudder twisted the aluminium rudder gantry that was nicely built but clearly not designed for those loads. I had a scary ride into the harbour with the foils 10 degrees out of allignment.

At this point, it was about 3 days before the nationals at cootharaba and i knocked up a new gantry overnight which was crap, but lasted the nationals. just. and shortened the foils to 850mm, though didnt cut them off, as the lake was meant to be a tad shallow. and it was definitely fun foiling (some of the way at least) into the shore when everyone else was getting out in neck deep water.

nationals:

the day before the regatta i went out on the lake and foiled around fine. need some practise. just before the invitation race i had a big crash and was not suprised to see the main foil in 3 bits. At the particular point when the boat is nosediving at 20 degrees doing 15kts, there is so much load on that foil from such a wrong direction that i couldn't see how all the others managed to stay together. in fact i couldn't see how mine had survived quite a few such crashes. I got to the shore with my few shredded bits of carbon hanging a bit limp off the bottom of the boat and it became apparent that all i had to do was tie the bottom plate to the top plate and strut. lots. then she'd be able to resist that negative load that i didnt really foresee. Sailed the regatta as a low-rider, (had to bite the bullet and do an overnight repair on the broken standard rudder) I found the boat to be fairly quick on the breeze but not downwind. maybe that was to do with my mast rake... or my lack of balance... did orrite in the end i was pretty happy. Brent ended up beating me, but i did finish the regatta with two DNFs.

anyway over the course of the regatta i broke:

2 sails. (one was emo's, i hope that fixed up alright)

1 hydrofoil.

1 dacron tramp. (stitching)

1 repaired t-foil rudder. (sheered off on the second last day in 25kts at the bottom gudgeon)

1 makeshift gantry. (didnt actually break, just elongated the holes where it attached to the boat)

So a year later im into it again, i have an opportunity to try some new ideas. i need a new foil, a new gantry, a new tramp, a new sail and the control system needs an overhaul. give me a month to psych myself up.