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Author Topic: Footy(s), beginners build  (Read 5864 times)

andrewh

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Footy(s), beginners build
« on: September 18, 2007, 05:22:54 PM »

Having followed the worldwide fun and frolics of various footy builds in other places I couldnt resist a try.

Being me the try has several lines of action;

1) build one with what I have
Plans for "razor" printed and built in 1mm styrene

http://footy.rcsailing.net/plans.php

(thanks, Bill for putting them there)

Pictures of early stages of build attached below

Mast is to be tapered carbon tube plugged over fixed tube of the same taper - I will bind the end of the Mast with a little kevlar to prevent splitting

Boom fitting, I realise, can be my favourite silicone tube flexy pliugged onto the boom (barbeque skewer)

Rudder (now fitted)  is styrene borrowed from scrapped yacht

Total time so far, a couple of hours and 2 nights to harden

2) review if I have any hull that is a latent footy

Dig out freestyle "Galleon" hull cut by my lad (then 10) with a hot wire saw

Hmmmm I wonder if a square rig footy would be A) fun and B) competitive?

3)  Prepare to mould a fibreglass/papie mache hull over quick and elegant mould - this will follow what I learn from the Razor and galleon

Plug and first papie mache hull (perfectly usable if you use emulsion paint as the goop - I used PVA the first time and got a soft hull when some water got in) - see attached pic of PMY



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romainpek

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Re: Footy(s), beginners build
« Reply #1 on: September 20, 2007, 12:12:18 AM »

Nice !  :) how do they sail ?
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andrewh

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Re: Footy(s), beginners build
« Reply #2 on: September 20, 2007, 12:58:18 PM »

romainpek - thanks

Don't know about the footy yet - its only moved one one session since the pic, and I didn't have the camera with me at that time
The Razor has a good pedigree and seems to accomodate several types of rig. 
I aim at present to give it a lofty bermuda rig  - possibly without mast stays, and probably with a bowsprit if required to balance up the areas, etc.

The yellow PMY (Papie Mache Yot) sails well, and better with each increase in sail area - this is the third  and largest suit of sails that it has had so far. 
They have all started life as golf umbrellas and been transmogrified into sailcloth after the wet and windy season in Britain (Jan to December)

Looking at it now the rudder is unfashonably low-aspect, but the essentials work well  - I will move batteries and rudder servo further aft to reduce the bow dipping when close-hauled

PMY is 24 inch long, and I have made a couple of epoxy glass hulls from the same plug, but never finished them (yet) 

I did wonder if pruning a pmy moulding off at 12 inches from the bow would produce a good Footy?  I could claim that it followed the flat, rounded modern style of Footy design!

Design comes from a "from-memory" copy of the little r/c yachts used at the UK National Maritime Centre in Falmouth, where my  lad - then 8 - had a great time sailing them.

I also liked the style of the vertical stem/big radius transom, and tried to  copy so that the lowest part of the transom just kisses the water when at rest (and probably when heeled, too)

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g7tmu

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Re: Footy(s), beginners build
« Reply #3 on: September 20, 2007, 05:02:08 PM »

Looks very good, must get round to building one!

Any chance of a few more detailed photos, of rig, fin, radio fit etc.

Thanks

Victor (g7tmu)


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andrewh

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Re: Footy(s), beginners build
« Reply #4 on: September 28, 2007, 01:22:13 PM »

Finally
Some progress and a camera in the same place!

Made the fin/keel - I have gone for 50 mm wide and left it at the moment a little more than 310 mm long to allow for trimming

Now I notice that many/several Razor footys have a WIDE low aspect keel with large amounts of area disposed towards the stern - well we shall see and I expected to tune the sails anyway to achieve balance!

Rudder borrowed from previous yacht, Fin laminated from 3/16 hard quarter-grain balsa with a 2mm carbon tube epoxied in.  All planed and sanded thin symmetrical section (Thinks - looks like a heli blade but it is also half an old-fashioned team-racer wing)

Rudder servo in place - sticky taped to a styene re-inforcing plate - generic 9-gram servo chosen becaise:
A)
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MikeK

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Re: Footy(s), beginners build
« Reply #5 on: September 29, 2007, 08:58:22 AM »

Now there's a cliff - hanger for sure  :o :o
Mike
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andrewh

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Re: Footy(s), beginners build
« Reply #6 on: September 30, 2007, 01:33:08 PM »

Apologies (abject type)

For unknown digital reasons (my finger got the wrong button) this posted in the middle of composition - I believe that I hit tab (on purpose) and saw the post happening

Now  just have to remember wth I was doing :embarrassed:

9-gm servo because:
A)   I have several spare
B)  I found that they are low enough to fit the tiller arm with a straight pushrod
C)  I gets the rudder servo out of the way of the sail servo arm!

Got some more progress and some pics yesterday (Saturday), but will have to cut the size down a bit before posting.

I have relocated the web sites with more information on Razor:

http://home.earthlink.net/~tigerprises/images/RAZOR%20FOOTY%20CONSTRUCTION/index.html
http://footy.rcsailing.net/razor-update.php

Pics follow shortly



 
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andrewh

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Re: Footy(s), beginners build
« Reply #7 on: October 04, 2007, 09:54:11 PM »

At last a little progress

I have been pounced upon by Angus and forcibly registered, so now I  have GBR118 tattooed across my brow and keep getting phone calls from people wanting phone nos. (For non UK residents 118 118 is a famous telephone directory number)

Fin attached, and a test sail tried in the DFTF - pictures attached

I have cast the bulb in a spare 15 minutes tonight, and it has come out, when tidied, as  310 gm, so the trusty hacksaw will reduce it to nearer 200, and with a slot cut out for the fin to go right thru I think this will put me in the right ballpark.

btw the ballast in the floating pic is 120gm of lead, and the bow and stern are just kissing the water.  Most of the radio gubbins is piled in the hull so the total weight is close to being right
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andrewh

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Re: Footy(s), beginners build
« Reply #8 on: October 05, 2007, 11:52:20 AM »

Bulb casting worked very well - I crimped together the end of a length of 15mm copper piping, set it up vertical on the floor held in a pair of self-grip pliers and poured in lead, topping up as it rapidly cooled and shrunk.

Pics attached of the mould before use, and the finished product

I had been aiming at 200 gm (7oz), and when I had cut off the sides of the fishtail at the trailing end the actual weight is 310gm for a parallel length of 160mm.

So by my dodgy maths the length for 200 gm would be 100mm (approx)

A little thinking suggests that I will be reducing the weight by slotting the centre for the fin, and a little by rounding the leading edge.  I can adjust the actual weight by drilling out some of the lead and replacing with filler or wood dowel, and adjust the fore-and aft detail trim by doing this at one end or the other

I aim to leave the copper in place, round the trailing end to a gradual taper on a grinding disc and round the leading edge to an approx hemisphere the same way - then paint the lead and polish the copper!
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romainpek

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Re: Footy(s), beginners build
« Reply #9 on: October 06, 2007, 02:14:24 AM »

Good idea !

You get something more resilient (like a full metal jacket bullet) and less toxic to touch !
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andrewh

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Re: Footy(s), beginners build
« Reply #10 on: October 08, 2007, 08:27:27 AM »

I'm hoping, too, that the copper will prevent the boat getting arthritis
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andrewh

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Re: Footy(s), beginners build
« Reply #11 on: October 10, 2007, 12:47:21 PM »

Progressing to rig - servos and arms installed

Bulb epoxied in place (having checked that the Razor fits into the box),  deck glued on and trimmed.

I have been inspired by some footy pics, and fitted the sail servo in the centre of the boat with a double sided sail arm (1.5mm Styrene)

Mast and gooseneck sorted - using helicopter balljoints for pivots screwing into a length of yellow snake inner tube
Booms are aluminium tube dia about 3mm - but selected to be a tight fit for silicone fuel tubing to act as retainers/adjusters

Since the mast is extremely thinwall CF tube I have wrapped both ends in Kevlar thread to stop it spreading - especially at the base where all the loads will be trying to ecpand the tapered tube

Sail patterns cut from Card, and offered up to available material - see pic.
I cut round the card patterns with a soldering iron (works for full size too)
  -luff pocket in both sails for mast and forestay
and do the usual reinforcement of the places where they come to points

No standing rigging - mast will be retained by a PEMRD* around the base - (a length of PVC tape) 
Forestay tension will be moderate but I can see the possible need to fit a backstay


Polymorphic Extensible Mast Retention Device
 
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andrewh

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Re: Footy(s), beginners build
« Reply #12 on: October 16, 2007, 01:41:08 PM »

With an approaching competition  - the St, Modwen trophy (last Saturday) some midnight oil was burned and gores from a golf unbrella became sails.  Rigging took an incredible time, but the next one would be much quicker.

I finished up with more than enough travel on both the sheets - and even made them adjustable, but had not floated the boat since the original ballasting session in the bath.

I was due some good luck and found that there was no need for the line that normally suspends the jib boom from the masthead (what is this called?  on a Thames Barge the similar line that hold the Sprit up is the stanliff)  Anyway not needed  - the tension in the Jib did this Ok

Long story short.  Floated, sailed, raced a bit, finished last and happy, learned a lot, flattened batteries, got retrieved (Thanks, Gary)
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andrewh

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Re: Footy(s), beginners build
« Reply #13 on: October 16, 2007, 01:42:43 PM »

Pictures missed from last post
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barriew

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Re: Footy(s), beginners build
« Reply #14 on: October 17, 2007, 07:23:19 PM »

Was there any wind at Branston last Saturday. It looks flatter than I've seen it all season in the photos.

Barrie
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andrewh

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Re: Footy(s), beginners build
« Reply #15 on: October 18, 2007, 01:32:14 AM »

Barrie,

In round terms, none.  the St Modwen was called off around 1.00 pm for total lack of wind

A few stalwarts stayed, laid out the internet course and had several racing laps in the slight and fitful wind in the afternoon

As you say the reflections are near-perfect - I took one pic of moonshadow where it is not easy to tell which way is up
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andrewh

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Re: Footy(s), beginners build
« Reply #16 on: November 20, 2007, 05:19:23 PM »

After what seems like a pause, RAV the Razor went to an open meeting at Bournville ( thank you Bournville club) last Saturday.

While present and participating we did not trouble the scorers much.

In mark 2 form RAV now has swing rig (Fixed mast)  using the same umbrella-nylon sails as before
She wears her smaller servos on the deck for ease and reliability, and has 4 alkaline batteries disposed in 2ubes velcro'd each side of the keel.

Alll good stuff, and I am enormously encouraged that the 2nd and 3rd boats were Razors made of tree-wood and well sorted and balanced.

Now all I have to do is to get RAV the Razor to the same state!

andrew
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DickyD

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Re: Footy(s), beginners build
« Reply #17 on: November 20, 2007, 05:25:04 PM »

Barrie,

In round terms, none.  the St Modwen was called off around 1.00 pm for total lack of wind

A few stalwarts stayed, laid out the internet course and had several racing laps in the slight and fitful wind in the afternoon

As you say the reflections are near-perfect - I took one pic of moonshadow where it is not easy to tell which way is up

Its not anyway up, its sideways.  :-\
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andrewh

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Re: Footy(s), beginners build
« Reply #18 on: November 21, 2007, 12:36:05 AM »

Really?
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