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Author Topic: Presto, a perfectly traditional Footy  (Read 27394 times)

andrewh

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Presto, a perfectly traditional Footy
« on: June 22, 2009, 04:23:42 pm »

I have built a range of footys ranging from slightly weird to REALLY distinctive including the submersible Footy (ZBF) a VAWT powered Footy (Soapfoot) and some other odd ones.

AndyT has shown us how he does the Pirate bottle boat;  I do use pop bottles, but shrink -form them onto plugs to make PET hulls.

However this is a return to simpler pleasures and tree-wood.  This is a Footy made of hardwood in the traditional style with progress pics.

Please feel free to ask anything as I go along - including would you please Stop.  :}

Whats a footy?
Basically a racing yacht that meets the class rules which (summarised radically) are that it fits in a box 12 inches long by 6 inches wide  by 12 inches deep.

Whats a Presto?



andrew
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #1 on: June 22, 2009, 04:47:57 pm »

Presto background.
Each year there is a design contest for the best UK design of Footy - called the Chris Dicks competition run by the MYA. 
I would post you details results etc, but for some reason links to it are concealed

In 2008 there were about 12 entries, one of which (Presto) was disqualified; so this is the one I am building.
The reason for disqualification is that the designer is a foreigner - Fabio Faloci.  I had suggested that he should have been Frank Featherstonehaugh for the day, but he is too honest for that.

Fabio is a Naval architect, boat designer and builder and sailer of boats footy size and smaller - his designs look like traditional craft but sail like modern ones with character.  I have raced against Flavio and his "Folgore" design and when I saw Presto asked him if I could build one to keep his one company :}

Although Presto has not been released as a plan, Flavio sent me the lines in a format I can use (6mm Buttock lines) since I carve hulls this way to aid symmmmmmetry. 

So I gathered 5 Sheets of 6mm balsa (told you it was a hardwood), made 8 photocopies of the side view and set to work:



andrew
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #2 on: June 22, 2009, 04:58:49 pm »

And the reason for 8 copies is that there is a keel (4mm thick) and 8 buttock pieces each side
I cut out the copies  - numbering them carefully - its very easy to lose count, lose the line (or fit one frack to bunt)
I cut them out with as knife - plane and sand to the line  - the line is 0.3mm wide so I try and sand to the middle of the line
This leads to a stack of pieces like this

or like this

At this point in the evening I had run out of 6mm sheet so I had to ajourn till the shop opened

Flavio has designed Presto to suit his one-piece radio system so the hull is basically solid with a rectangular cut-out which the eagle-eyed will have discerned.  I aim to make the hull basically hollow - about 10 mm thick, so there is quite a lot of middle to cut out
This is what the complete stack of bits looked like when they were cut and sanded to shape


and from the other side

andrew
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #3 on: June 22, 2009, 05:15:07 pm »

Dinna fash yersel about what looks like misalignment - these are just clamped for photo purposes.
There is a lot of sheer in the design - have a look at the side view

I have been experimenting with using a BIC disposable razor as a spokeshave to plane down that inside curve of the deck.  Not perfected yet - so most of it is done with the thumbplane - always towards the centre so it doesn't grab the grain and take off the entire stern :((

Where, I hear you ask is the ply keel?
It got overtaken by events and has become a 6mm hard balsa keel.  It has two major cutouts in it - one for the keel to be inserted (ALL my footys from now on will have removable keels and rudders) and the other to house the mast.  The mast hole I made 10mm wide in the fore-and aft direction to allow for some adjustment of position and rake - the rake is important to the right "feel" of the boat

This is an interim stage where I have the buttocks pinned together while sorting out the inside shapes required
more as it happens
andrew
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amdaylight

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Re: Presto, a perfectly traditional Footy
« Reply #4 on: June 22, 2009, 07:54:52 pm »

Andrew,

You perchance might have a set of section lines from Fabio Faloci? I might be tempted O0 to build one of these with a little modification to the bow.

Andre
over yonder in Portland Oregon
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #5 on: June 22, 2009, 09:20:32 pm »

It MUST be an andre/andrew/Andy thing! :}

Best thing to do would be to ping Flavio - I will Pm you his details -  and see what he says. 
I know that Presto is intended to be published, and I have pleaded  to be able to build the first apart from his - we may get to sail them together at Birkenhead next month, old Gaffers indeed!

I know he is concentrating hard on the Mystic wooden boatfest for which he has built and sent "Brando"  - which is unspeakably lovely, too

I have never met a mother yet who is offended by praise of her offspring!
andrew
Over here in blighty
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #6 on: June 22, 2009, 10:48:50 pm »

Jut to jump foward in time

Tonight this is the state of progress
All the parts glued up, finish sanded outside, transom largely finished, and the one ding mark repaired with a triangle of balsa let in using balsa cement






Next post - back to the past
andrew
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andyn

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Re: Presto, a perfectly traditional Footy
« Reply #7 on: June 22, 2009, 11:42:31 pm »

Looks good :-)) Good old wooden stuff O0

When are you going to make an ultralight Carbokevlar one then? ;)
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amdaylight

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Re: Presto, a perfectly traditional Footy
« Reply #8 on: June 23, 2009, 06:39:24 am »

Andrew,

Thanks, boy is that looking good.  O0 O0 I have a soft  spot for antique look boats. I was out sailing my Fairwind 3 this after noon, I had forgotten how much fun and how relaxing it was to go sailing for an hour or two.

Andre
over yonder in Portland Oregon
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #9 on: June 23, 2009, 08:16:55 am »

Andy,
Bin there, done that.  Voortrekker. 
It was/is so light that it stops as soon as the drive stops - like a racing catamaran. 
Mind you, its sister made by Gary has won competitions so perhaps I am just a RUBBISH sub-optimal footy driver :((

Andre
as well as the carbokevlar and directionally-oriented PET  I do love tree-wood and an excuse to sniff balsa cement
I ahve just finished builfing Blackwatch for a canadian friend

she is designed specifically to beat the internet course record

Back to the chronological sequence
We have 8+8 balsa buttocks, and another 6mm Keel, which is cut out for the removable fin, mast position, and I cut some lightening holes in the bow as well.
Before assembling I have cut out the centre of the planks to make the boat hollow - it is very difficult (for me) to do much hollowing after assembly - I do not have any scooping tools or balsa - probably should make some or get ball-ended Dremel cutters :}


So I have dry assembled all the parts, satisfied myself that they fit and now we head for the glueing phase
andrew


The buttocks are assembled using polyurethane glue with saliva as accelerant


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dreadnought72

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Re: Presto, a perfectly traditional Footy
« Reply #10 on: June 23, 2009, 08:47:14 am »



That, Andrew, is uber-sweet. Were there plans around, I'd like to do a plank-on-frame one.

Andy
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amdaylight

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Re: Presto, a perfectly traditional Footy
« Reply #11 on: June 23, 2009, 08:50:16 am »

Andrew,

All right I will bite, where did you get color coordinated glue from, red to port and green to starboard no less.

Andre
over yonder in Portland Oregon
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #12 on: June 23, 2009, 09:21:28 am »

Yippee, Glad you asked, andre :-))

I don't  - the PU glue I am using at the moment is in fact pinkish - but some are blue, green and yellow.  I am sure that some determined work with food dye would colour the glue.
When the planks are ready to glue I paint the inside of each buttock about 12mm wide with (very dilute) acrylic paint
 
In this case Italian colours - red at the hoist and green at the fly :}

This pic also shows that I tend to assemble the hull as three bits - two "shells" and a centre bit with keel.  The inside shape of the centre laminations is more or less parallel to the outside shape, so it is not too difficult to sand them as a stack of five or so
At the same time I can glue up outer laminations on both sides - it all helps with speed and the size of clamps

Alignment
I build from buttock lines for several reasons - mainly to do with my abilities (and doubt that if I worked with waterlines I could achieve the same symmetry of hull shape)
First it is not difficult to make two buttocks the same size and shape - I trace off a template and EVERY part has all the buttock positions marked on the top (deck surface)
Second, and with my paint "marker" I get a good view of the hull shape as it is finally shaped - any irregularities in the lines shows as a serpentine wobble in the paint line
I align everything off the deck surface, using the buttock locations to fix the fore-and aft location of the next part

Hull showing alignment marks, etc.

When glueing with PU two things are important:
A) moisture - it needs water to cure, balsa is the very worst thing to glue (as with cyano).  Wet it with a sponge or lick it :}
B) Clamping - PU foams as it sets.  It WILL force the joint apart - all PU joints need to be clamped
C) ALL UNCURED PU IS INTENSELY POISONOUS


This is the whole hull glued and set
andrew
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amdaylight

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Re: Presto, a perfectly traditional Footy
« Reply #13 on: June 23, 2009, 05:46:00 pm »

Andrew,

When you say PU glue, I think that your are talking about something like Gorilla Glue. Is that correct? And if it is then the food coloring would set it of as the carrier in the coloring is water. But since you explained that you paint part of the laminations I now understand.  O0

Andre
over yonder in Portland Oregon
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roycv

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Re: Presto, a perfectly traditional Footy
« Reply #14 on: June 24, 2009, 10:06:08 am »

Hi all, I recently built a similar size yacht and was looking around the shed for a long keel and espied an old 3 foot (one piece) wooden rule, cheap boxwood, and this has proved effective.  Now my 3 foot rule is a 'footie'.
regards Roy.
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #15 on: June 24, 2009, 01:00:35 pm »

Thanks for your input, chaps

Andy - so you are recovering from plank-fever enough to consider something like this, eh.
The design is by Trevor Paetkau and I will just check with him, but I guess he would be chuffed to (whatever Canadiens get chuffed to) for you to do a POF version.
btw my build log for blackwatch is here
http://www.rcsailing.net/forum1/showthread.php?t=5226

Andre
You have it right - Gorilla Glue is a Polyurethane. 
I have tried it and found that it is A) staggeringly expensive - about 10 times the price of what I use
B) relatively slow to cure (overnight) and remains rubbery even when cured
So I use a locally bought carpenters PU which claims to be 5-minute (and this claim is as accurate as 5-minute epoxy)  fully cured in 20 minutes.

Roy - I think by my arithmetic you may have created a Yardie.  Some of those rules are made of boxwood - they would be wonderful as a source of boxwood for making "blocks"
andrew
next build segment follows
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #16 on: June 24, 2009, 01:07:10 pm »

I have now marshalled some of Flavio's sketches for Presto and similar footys


This is his one-lump radio pod that fits in the square well drawn on Presto drawings



Presto in all her glory - watch this space!

This is Flavio's Brando - which is considerably similar and is now in the US being warmed-up for (wooden) footy racing at Mystic

please study the finish, detail and general atmosphere in this pocket marvel - I am smockraffled at how much character he has packed into 12inches
andrew
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dreadnought72

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Re: Presto, a perfectly traditional Footy
« Reply #17 on: June 24, 2009, 01:58:01 pm »

Andy - so you are recovering from plank-fever enough to consider something like this, eh.

I think it's the fun of sailing, coupled with the speed by which I can get "something" on the water this year.

The design is by Trevor Paetkau and I will just check with him, but I guess he would be chuffed to (whatever Canadiens get chuffed to) for you to do a POF version.
btw my build log for blackwatch is here
http://www.rcsailing.net/forum1/showthread.php?t=5226

Many thanks - I'd appreciate that.

As to the rcsailing forum, I noticed there weren't enough Andys on it, so I joined at haste yesterday.  :-) Still reading away at posts there.

Incidentally, the class rules, as my brain endeavours to absorb them, seem to not place a limit on bowsprit or bumpkin length, only their diameter, nor on the larger rig's height. Obviously the limitation to keel depth is invoked by the "fit a box" mentality, but it seems like over-canvassed boats might be the (unfortunately) tempting result of home-brewers working on their first. Is this correct?

As to Flavio's Brando, I've been following the rise on interest in footys on the Wooden Boat Forum. (There I don't post - I just gaze in awe at the woodworking skills on display. Plus they probably have enough Andys.)

Andy
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #18 on: June 24, 2009, 04:46:06 pm »

 :}THERE CAN NEVER BE TOO MANY ANDYS :}
Part of the joy of Mayhem is the plethora of assorted Andys

There is no limitation of bowsprit or bumkin length - but the real world imposes one since too much is a liability when one is rounding distant mark in the company of other boats.

My habit used to be to maximise the keel depth by using ALL the box height, but I ran foul of a NSL* who insisted my sheet fairlead (a 3mm screweye) was part of the hull and had to be inside the box.  So now all fins, etc are removable and I make them 1/2 inch short of the maximum
*Numpty Sea Lawyer

Footys are very sensitive in balance, as you can imagine (rather like a peanut aircraft if you know what they are like) and also easy to over-canvas.  For racing (at the moment ) you have to measure with a rig which is less than 12 inches above the top of the box and use that and one other rig for the whole "meeting". 
If you pic a low-wind rig as your second rig, and the wind rises - you have the choice of trying to sail on yer lugole or fitting the 12 inch rig and pottering slowly but comfortably.
andrew
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amdaylight

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Re: Presto, a perfectly traditional Footy
« Reply #19 on: June 24, 2009, 06:15:53 pm »

Andrew,

Now that is a miniature yacht.  O0 I stand in awe of Flavio's Brando, as you say the finish and detail are just .. just oh well I am at a loss for words. I now know how high I have to aim. O0

Andre
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #20 on: June 25, 2009, 12:58:33 pm »

Yes, Flavio has a lot of talents and is happy in sharing his knowledge :}

There are several more of his sketches  - I will have to convert them out of PDF to be able to post them



His design and build log for Brando is at
http://www.rcsailing.net/forum1/showthread.php?t=5147
and a lot of his wonderful sketches are in there as well as philosophy, etc.  He also designs much smaller models and full size boats
Google "faloci+dodo" or faloci +duckworks to get a look at them - notice there is a perfect little model of the full size design submitted with the design!
http://www.duckworksmagazine.com/06/contest/9/index.htm
andrew

more build next!
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #21 on: June 25, 2009, 01:08:56 pm »

Keel layout

The centre lamination of the hull is 6 mm thick, and has a tapered fin-box to take a removable 6mm fin.  I did not take any pictures of this part of the build on Presto – but here is one from the build of BlackWatch which illustrates the construction of the fin box from the keel and the two surrounding buttocks.

This is a picture of the keel box  - very much the same as fitted into Presto.  The hawk-eyed will have noticed that the keel box is open at the front - this is because BW will probably sport a MacRig and the mast position needs to be close to the front of the keel box - it got a closing slip of 1/32 (0.8mm) ply later in the build

Onwards and upwards

Hull is fully glued up, and at least most of the inside surfaces are effectively in the final shape.  The outside surface is “stepped” so the next  task is to just remove the steps using a razor plane and sanding block, and in that order.

As I get older I get a little wiser – this time I did the plane work directly over a dustbin – this took about 15 to 20 minutes
 

Then it was the turn of the sanding block – I use an ancient foam block with removable Velcro pads – it gives a good combination of soft backing to deal with a rounded hull, and is flat enough to sand across the deck area (although I finish with a wooden sanding block to avoid rounding the edges)
I don’t care much about the coarseness/fineness of the sandpaper but I care a lot about the quality and sharpness.  I deeply advise you to get suitable “sandpaper”.  For wood it doesn’t matter if it is aluminium oxide or silicon carbide paper  but it should be called something like “open coat” or “production paper” and it should feel open and sharp to the fingers.  In modelling use we never wear it out – it is more likely to get clogged or torn or suffer accidents with smears of glue!

Plane from the hull centre to both ends – take small cuts, approach the final shape gradually, keep turning the hull over and viewing it from all angles.  Using the coloured tracer means that you can compare the two sides directly.

You have reached the correct shape when:
•   You have JUST removed all the steps so that only the coloured line is left
•   The bow looks central (I run a line of permanent marker down the centreline of the keel to help keep things symmetrical)
•   The stern/transom looks as you would like it to, and is the same on both sides of the hull

When planing you need the Sharpest blade – plane only with the grain, and from the middle only towards ends,  plane with the blade at and angle to the grain (My plane has the blade set at an angle but feel free to hold you plane at 15 or 20 degrees as you plane)

Sanding
This will be in 2 stages – roughing and finishing, and the transom will need special treatment (because it will be all end-grain wood).

Rough sanding is to take out the plane marks and flats, and produce a completely level surface which is the hull shape you want – only not perfectly smooth for the next process

Finish sanding is to get the wood finish you want without changing the shape.

Remember that balsa is a series of cellulose “tubes” lying parallel to each other held together by a very small amount of glue (lignin).  So wherever you have end grain you need to fill the tubes to prevent water getting in (Remember the Kon-tiki sank - as all balsa does if the end grain is not protected.  Remember too that the word Balsa means raft!)

Never try planing end grain!
It can be done, but not on balsa, not with your razor plane and not by me or you.!  I use a very sharp new snap-off blade to shape the transom – cutting always towards the centre of the transom and supporting the hull on a cutting mat. 
I aim to get the transom smooth and finished mainly by sandpaper.
andrew
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #22 on: June 25, 2009, 01:15:32 pm »

I'm working under (another) handicap at the moment - this text box I am typing in is behaving funny!

The last post was full of disjointed advice  - I could not intersperse the pictures - here they are:



The last 2 pics were done purely for illustration  to show the "stepped" and smoothed sides (in this case BW)


Presto transom after knife-cutting to shape, but before smoothing with sandpaper

We are now here

andrew
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andrewh

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Re: Presto, a perfectly traditional Footy
« Reply #23 on: June 25, 2009, 01:20:26 pm »

Andy,




That, Andrew, is uber-sweet. Were there plans around, I'd like to do a plank-on-frame one.

Andy

Trevor has blessed release of the plans, etc and I will get them to you - all the transverse sections etc are there too  - the hot set-up is to arrive at the precise length first - then everything on the sheet is the right size!
Note - it is the hull/foils only.  there is a layout plan showing mast location for a Macrig - if you want conventional or swing rig there is a little more work to do :}
andrew
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John C

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Re: Presto, a perfectly traditional Footy
« Reply #24 on: June 25, 2009, 05:04:01 pm »

Superb
I can't wait for the next instalment. I've often considered building one of these, but for the most they all look fit for the purpose of racing and I don't do that.
I am inspired though, and have been checking out local shops for graph paper!! seems they only do it in A4 pads these days....... but then there's always selotape.
I like the traditional look, but I don't want to build what's been done before. So all line drawings are of interest to me, and hopefully at some point I'll come up with something that appeals to me.
Keep up the good work

John C
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