Day 59
Days remaining: 175

Build it strong... - 4g is a lot!....

This G Meter goes down to -ve 4g

Just about enough for a Moth.

I'm building a lot of my boat stronger than I would build a 14. I'm on my weight budget to have a boat around 9.5kg, but some bits might look a bit rugged for a moth... I care not.

My worst case load test in my head for a 14 is a nose planting down the bottom of a wave, from max chat to almost stopped.  It is rare, and the fastest I've ever sailed a 14 is about 22 or 23 knots.. and we were so chicken we had the rudder wing on max bow up and never crashed it. If it ever got really sketchy, you just came off the wire, slowed it down and had a bout of tourettes...

A Moth will see 30knots or thereabouts max. High twenties are common when racing.  I predict that in 5 years boats will be reaching speeds higher than Crossbow II's 1980 top speed (and at that time World Speed Record) of 36 knots....

....and the classic main foils popping out at speed and the inevitable 30 degree nose down 'stick thrown into the pond' stop is commonplace.....

Well staggeringly that sort of a crash is a Negative 4g acceleration (or a 4g deceleration if you prefer)

Here's my maths to support that by the way..

Quick conversion first... 1 knot = 0.514 m/s so 30knots = 15.42m/s... So we'll use that speed as our start point.

A moth is 3.355 m long.   30 knots = 4.7 boatlengths per second  (Yeah, pause at that point- Crikey!!)

Crash stop from 30 knots to a dead stop = 2 boat lengths = 0.425 seconds... Which when watching video of pop-out / spear in crashes, and experiencing a few of them as everyone has, that seems about right....

Deceleration from 15.42 m/s to 0 in 0.425 seconds is around 36.28m/s/s (my mac doesn't do little uppy arrows to do a 'squared' it seems!)

1g = 9.82 m/s/s

36.28m/s/s = 3.69 x g

So all this time, the moth really has been pulling 4g negative dives, just like in the film!!


D

Day 58
Days Remaining 176

23/1/2014

Around the Buoy!!!!

Back in the bad old days of the Navy, way before my time... When Nelson still had both eyes and the Dead Sea was still just sick on shore, new recruits to the service would find themselves learning the ropes, literally, at HMS Ganges on the Shotley Peninsula in Suffolk. Whether you were destined to become a mechanic in the Fleet Air Arm, or a stoker in a warship, a cook, a clerk or a deck hand, you went to Ganges and learned to march and clean your kit and do as you were told and grow up. Real fast.

Up until 1976 Ganges was the new entry facility for the RN... And in it's time boys as young as 14 could join there, though the average age of a baby sailor was 17.  As you can imagine, it was a tough life from Day 1. Bullying was rife, the food was poor, and having a quiet chat with your Divisional Officer to explain that your pillow was a bit on the firm side wouldn't have happened. The instructors were notoriously savage and beatings for poor drill, dirty kit and lateness were common not only from the staff, but from your mess mates who would also face extra drill and duties if one of the division made an error.

There were many things Ganges was famous for, and while lenience and tolerance were not two of those, manning the mainmast and rowing of whaling boats in the estuary certainly were.  The former involved 80 volunteer boys of the ships company manning the 143ft mast - and yes the Button Boy would shinny up the last 15ft of topmast, then climb around and onto the button and stand supported only by a lightning conductor at his back... And Salute!

The latter, shown briefly in the film, is the boat section. Boys were taught to sail and row in whalers in the estuary and out in Dovercourt Bay, come hell or high water. Literally every day of the year the sections (age groups) of boys would take it in turns to be out first light, rowing the mile and half each way to the Harwich Harbour buoy (in front of the original Trinity House) and back.... The last boat home would pay an awful price as the duty instructor would be standing waiting for them at the end of the pier and if he felt that they were last through lack of effort, would point back at the Harbour entrance and shout...  "AROUND THE BUOY!!!!" and they would have to do it all again...

The phrase became commonplace in the RN for instructing a subordinate to repeat a badly performed task... And this week I am afraid I have been Around the Buoy a few times on the working deck of the Blackbird... It is a simple piece of carbon on foam core, but the inserts for the cleats and fittings were wrong in the first and the second fitted, but not well enough.... Finally in cure as I type is the 3rd and hopefully final version....

Sometimes I gain inspiration from looking out of my back window where I can just see the top third of the mighty Ganges main mast... This week I certainly have.

D

Day 49
Days Remaining: 185

When the going gets tough....

It's not me. But it could be.

Crikey I am beginning to hate the whole running thing.  I used to love running. Bounding, gazelle like, between puddles, accelerating like a hare across busy roads, climbing hills as if they were gentle declines... Where did all that go?! Beware my brave lads... When you get to 45 you are going to struggle to find the form you had when you were 35, let alone 25... and seeings as some of you probably think 25 is OLD... Just you wait!

Still, tomorrow's a day off the phyz thing, and I can look forward to a lie in and just a walk down to the marina and back to loosen up.

Now then... The boat....
Well I forgot to mention something apparently... It's got a nomex core... It's actually M40J prepreg on Nomex, but that's not that important, any carbon skin on Nomex is going to act like an HM material provided it's stuck on properly... I got hooked on using nomex when I built my last 14... not just for the way it feels in the water (like you are sailing a boat made from shards of steel struck from the hammer of Thor, or something!) but I really like making things with it cos it's so easy!  Anyway, yes if it get's holed I'll sink without a trace... If Tom O wants to duck me, I'll let him! :-)

Sort of sticking it all together now... Taking a little time to line it all up, but it will be worth it... and yes, I know I wanted to be sailing tomorrow, but real life means I couldn't anyway because it's going to howl again!

D

Day 43
Days Remaining: 191

Skinny-Mini-Malloo

Looking ever so slightly like a reindeer - good job it doesn't have a red nose! (D'oh!)

When, in the early 90s I was running in the Field Gun Crew for HMS Seahawk and HMS Daedalus in the jolly old Navy, us Fleet Air Arm types used to sing 'Skinny-Mini-Malloo' whenever we heard one of the Devonport (ie Plymouth) crews sing their famous 'Oggie Oggie Oggie' nonsense.  Always made me smile. It's meant as a total piss-take and I am glad to say it usually worked!

ANYhoo!! Yes. Skinny isn't it! The boat is very narrow. Narrower than the M2. Maybe about the same as the early Ninjas? Maybe even narrower. You can see the rear rack tubes are on and the bow cover is made so all the wand mech and forestay gubbins can keep safe and warm and dry under the front and not get in the way of the air molecules hurtling past at 15 metres/second.

Couple of ups and downs this week so far.

-ve. Got to say that whole front end is taking some time. When you see a Mach 2 with all the wand gear 'tray' open and you think, oh that's clever, it really is! When you build a boat from scratch on your kitchen table and you want to do something similar, you have to do it before you fit the mast bulkhead so that you can put the tubes through that carry the push rod and the control lines etc... It's a lot of faffing about, making components from scratch, making sure it all fits, fitting screws from the back of panels so there's something to mount the wand mech on... It's going to be worth it, but it is taking days not hours... Little bit of project slippage I can deal with though as in the long run I'm not missing a lot with this rubbish weather and the boat will be so much better from day 1 (or Day 60 or whenever it is it gets launched)

+ve... I am pleased to say, dear reader that since I started this adventure I have lost nearly 2.5Kg so I am safely in the low 72s now... Skinny-Mini-Maloo again you see!  Now I've nearly lost the fat % I needed to get rid of, I am feeling a bit more confident about getting back in the boat and putting some shoulder strength back on. Already I'm finding the press-ups and the tricep presses easier but I have a long memory... Mothing is hard work, especially on the arms and shoulders...

AND FINALLY..  a BIG +ve to end on. I finally got round to dropping in on Rob on Monday and we've done a deal for the rig he won the 2013 Nationals with.  Mast and Sail... Great place to start from and a good solid performing set up... No excuses and I'll be able to compare a lot of data.  Another box on the plan filled with a big tick!

D

Day 40
Days Remaining: 194

Sunday 5th January

Moth Building.  The 1000 piece jigsaw without a picture.

Find the corners first - then it's a doddle. Yeah, right!

I was explaining to a friend of mine the other day, what it is like to build a moth.  One design boats have class rules that provide tight specifications - the picture on the box is pretty clear and the instruction easy. Make the puzzle like the box - all the bits are there, and they fit perfectly.  Moths are different.  11ft, x 7'4" x 8sqm... No cats, no cheating the RRS... Go! No picture on the box, no instructions, no idea how many pieces, no clear idea of where they all go or how they are joined and.... and in the end all you have is some parameters thanks to Reynolds numbers, density, UTS and Modulus of materials and your own wits.. oh and then when you have figured it out you need to have the skill and patience to put it together... In your kitchen....

I say no picture - you do kind of know what it should look like if you look at what's out there, and for that you have the current cream of the crop....
The Rocket looks awesome - the product of nearly 10 years of fascination with all things carbon on water and a big heap of left field, off the wall, tea fuelled "why not?"  Maybe its the Bristol connection? The home of Brunel et al, Bae at Filton where they were building string-bag fighter aircraft for WW1 and went on to build all sorts of fast jets and commercial aircraft.  Rolls Royce's very own Skunkworks for engine design was also at Filton...  Add a bit of Nick Park's Wallis and Grommit design style - again all products of the region and you'll be getting the idea! What is for sure though, Cookie's boats have some real pace and work very well..... and they have a wand on a sprit a full 500mm in front of everyone else's and I think I am right in saying the longest foil platform (distance between main and rudder foils). Gotta be quick.  Genius.

The Exocet looks like it was designed by Pininfarina with the numbers crunched at Bletchley Park and then the drawings taken in a velvet lined oak portmanteaux to Gaydon where gentlemen in white coats smoked pipes and carved the thing from the finest walnut and cherry they could lay their perfectly manicured hands on.  If you have to look up who they were, what they did and still do at those places, you're sailing the wrong boat. Go and buy a Laser.  It is exquisite to look at... If Ian Flemming had ever written his heroic assassin into a sailboat race, he'd have turned up with an Exocet. With Union Jack trampolines. Except I have to say that being a Naval man, he wouldn't though would he... because Flemming/Bond might, like me, find the name abhorrent and that it reminds him too much of the horrors of the Falklands War and in particular the loss of the British sailors and airmen of the Royal Navy on HMS Sheffield, Atlantic Conveyor and closest to my heart, HMS Glamorgan, which came under attack from an Excocet and was turned to head away from the missile, presenting the smallest target and saving the ship, but killing virtually all of the maintainers and aircrew of the ships flight when first the missile exploded and then the fully armed and fuelled Wessex aircraft ranged on the flight deck turned into an exploding fireball.   Jus'so you know the full story.

What next? Name a brilliant and ground breaking chain of kiddies play centres 'Auschwitz'?

Then or firstly perhaps, there's the Mach 2. If Bond sailed (name change pending) an Exocet, then Darth Vader, Batman, Jason Borne, Bora Gulari or any other hero or anti hero you could name would sail the M2... Except, instead of it being specially made and monogrammed and handed over by a man in a white coat called 'Q', they would get one from a vending machine on a street corner.  It is awesome yet it's brilliance is it is so brilliantly universal. A platform to base multiple upgrades on... Such a fantastic concept. On V6 of the foils and want to go a little faster, Sir? And you weigh 77kg you say? Oh well you need the V7.2 foils and while you're at it, how about the new Mode 3 Ka21 sail on a M65J 30mm 3 piece mast....? Fancy a colour change too? That boat will be winning championships when I am getting reprimanded for pinching the arses of the nurses at my retirement home...!   (Stop Press_ Now I really don't have an inside steer on this, but I have noticed a particularly well decorated British Mothie who might have had a hand in the M2 made a trip to Oz recently, and I listened (or read maybe) with interest the Jedi Lord AMac saying he was working on the aeropackage and a 'sort of wing'... or did I dream that? Maybe the Blackbird will be late to join the Mach 3 party? Good job it's set at M3.3!)

SO, I kind of have a picture on the front of the box - it's got to be as well set up, bomb proof and easy to adjust as the M2, it's got to be faster than that Exco mainly because true British pride is a stake, and it has to be as forward thinking as the Rocket, because otherwise it will be out of date before its maiden sail.... and like all moths it has to look fantastic, even when it's in it's box and flying to somewhere sunny where the water is blue and the sun is hot and the breeze is 15 knots all day and the beer is cold and girls are....................zzzzzzzzzzzzzz

D

Day 37
Days Remaining 197

The Moth Factory

Polystyrene blanks for gantry and compression struts

ready for gluing to an MDF base for mould making.

It's official. My house has become a moth factory... It's not as clinical as the workshop, or as well equipped, but it is warm and dry and there is tea. Lots of tea.

As I type the kettle is boiling and the following items are glued up and curing off.

The Bow Fairing.  Location: Dining Room Table.
The bow on the Blackbird is very blunt and full - This looks odd compared to a water cleaving points that we are used to, but water cleaving pointyness stalls very quickly and causes a lot of drag in the air, and the most usual mode for the boat will be airborne, heeling to windward, with an apparent wind speed of 10 to 35mph at an angle of somewhere between 22 and 12 degrees, and - a sharp bow will be very stalled after about 5 or 6 degrees.  A rounded bow, will have a higher stall angle and should be a significant factor in keeping the platform drag numbers down.

How will it perform in water? - ie low riding or in transition? Depends how it is set up I guess. If we set up with a bow down trim it will push a fair bit of water out of the way. Bow up a smidge and it should be fine. That's what testing is for.

Oh there's something else about the bow you might like. It is asymmetric.  To allow the wand to be closer to the centreline, the bow is kind of rotated anticlockwise when looking from the bow to stern. It affects the flow over it not one jot, but the wand is in a better place and puts less strain on the wand mech to stay linear, which means it works better across the range.

The Wing Bar Sockets.  Location: Kitchen Floor.
Finally I got my head around how to do this - I want the wing bar sockets to be bonded together and laminated to form an elbow that is completely watertight before they get bonded into place as they pass right through the boat - if they leak, the boat will leak... So they need to be at the right angle when bonded together. I got the geometry of the racks from studying a lot of pictures, and figuring out rig loads and such. The front bars are at a compound angle (ie they rake backwards AND upwards) and the total included angle came out at 122 degrees.  The rear wing bars come outwards perpendicular to the centreline, so are only angled upwards (at a similar angle to the front bars) and that makes the rear bar elbow a shallower angle of 139 degrees.  Once these were known it was relatively easy to set up a bit of geometry on the kitchen floor (floor tiles can be surprisingly accurate to use as guidelines!).  They are curing off now.

The Gantry Moulding Blanks.  Location: Utility Room Work Top.
The Mk1 Gantry I want to try is pretty punchy. It is made up of aero section mouldings (and no tubes) to form a rigid structure in a sort of H section.  The individual aero sections are NACA 0008 and the longest is 580mm in chord. I'm currently preparing the CNC machined polystyrene surfaces to make moulds from them and the parts will come from those moulds. Fitting the gantry is a while away, but these things TAKE a while!

The Compression Strut Mould blanks.  Location: Utility Room Work Top.
The all important compression struts that link the chain plate to the mast post are highly loaded. The Mk1 rack arrangement for the boat uses round wing bars with fairings, but the comp struts need to be all carbon, so I am making a mould that will produce an ellipse of the right sort of proportion and size (about 22 x 50mm) An aero section would be better of course, but that would have a sharp and fragile trailing edge. I don't like compromises, but in this instance, an ellipse is ideal - and I can always make a stick on trailing edge fairing for it for race days......And you guessed it, the Mk 2 front wing bar assembly uses the same tube for the comp strut as it does for the wing bar, with the inboard end transitioning into a tube to slide into the same wing bar socket.

D

Day 36
Days remaining: 198.  1st January 2014

New Years Day - Not that quiet at Blackbird HQ.

I woke up this morning and it is of course New Years Day... I wish all my moth sailing mates all over the World, and you dear reader of course, a happy and prosperous 2014 and I truly hope that if you are a mothy, you are starting to get excited about the Worlds, now less than 200 days away...

Bit of a private party at the Blackbird HQ last night making 2014 start with a bang, but that's enough of my private life!  January is always a dry month for me. Usually, only so I appreciate a good glass of wine better ;-), but this year, I'm actually looking forward to it.... I put on under one Kilo over the holidays and still closing in on my target on my chart.... Result!

My resolution this year is that every day the boat will get quicker and I will get fitter.... and remember, every day that I am developing the Blackbird, or doing some daft Pilates stretch, or running/cycling/swimming my 46 Summers old frame around the local bridleways.. Every step, every crazy idea, every drip of sweat, I am focussing on making the boat+me package faster around the track on Race 1 (through however many) at the Worlds in July.... I'm not rattling my sabre, indeed this is a friendly statement... Some of you are a long way ahead of me on pace, some of you are going to be the same speed as me, and some of you will be behind me... Every day I try something totally crazy on the lake, or in the workshop... Or come in from running to load my washing machine with my mud covered running kit, and scrub my trainers ready for the next day's torture, I am doing it to catch you, to overtake you, to leave you further in my wake.... So Thank You for being there, every step of my lonely cold dark slog, wherever you think you are in that imaginary running order, you are my target, my prey, my motivation.

Happy New Year.  198 days to go.  Lots of boat work to do to right now, but I don't go back to work til the 6th and that is 5 solid days of graft away - and some muddy runs of course...

Catch me later!

D :-)