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[Born Slippy]

I'm in Holland at the moment, but will post as much of the spars/racks/stump cookbook we used on the Exultant page tonight and then confirm the measurements over the weekend.

Careful though - too early to tell what will break yet!

[doug1720]

Thanks, some pics would be good.  My address is Doug Hassell, PO Box 500516, Dubai, UAE.

I am interested in some details on the racks.....sizes, best mandrel diameter and layup.

Thanks,

Doug

[doug1720]

Thanks.  Info would be good.

Doug

[phil_kirk]

Doug

PVC tubing intended for DIY use but can be used for mandrels can be found in such stores as B&Q.

from memory these come in the following Outside diameters.
12mm not bad for goose neck attachemnt in boom
19mm? good for small diameter struts perhaps for a gantry but small diameter tubes are difficult to make well
25mm good for tiller extensions, gantry struts, supports to a high mast stump.
32mm good for tillers
40mm  good for tillers (but we use 32mm) beams connecting racks to hull
53mm good for rack tubes or beams connecting racks to hull.

The tension stays beneath the forward beams on the elways are made flat because Andy P and I used rectangular section beams laminated round a high density foam core.  It is easier to join a flat stay to a flat surface of the beam.  It may be easier to join a round section to a tubular cross beam. 

I made the mould for the stay from a flat bit of wood and glued  a wedge to the end at an angle of 30 degrees. sanded it filled any gaps and cover it with parcel tape. 
Once I had used it I gave it to roland.  I would agree that some layers of weave would provide some impact resistance.

I don't know what lay up Roland used for the racks.

I can provide you with the layups that I used for other parts on the understanding that I can't gaurantee they are correct.  I have put full rig tension on the boat without a squeek from her but not sailed her in anger.  I expect all is ok but the lay ups would be unqualified.

[Born Slippy]

Exultant's layups are here:

http://www.sailingsource.com/cherub/test/doku.php/tech/3206build
Diameters and tapers to follow on that page at the weekend.


Sails,
Doug is also keen to try to get hold of an older set of sails for his early voyages? This is definitely the place to share this...

[doug1720]

Hi,
Thanks for the information.  I am taking next week off and so plan to make some progress.

In terms of sails I am planning to order a new set of sails but would like to have a spare set....I definately do not want to put the new sails up and go sailing for the first time and something goes and I have a big hole in the mainsail!

So I am very flexible on the state of the sails, just training sails.

Any thoughts?  I will put pics on the site.

Thanks, Doug

[doug1720]

Been working on the mould....final filling and sanding and brown tape and release agent.

Then put the inner skin on this morning.

Pleased that all went OK although took me longer than I thought.  Vacuum went OK although took some time to find all the leaks!

Also working on the daggerboard and will be sanding this tomorrow....can be seen in the background on the pics.

Used a 50:50 mix of very slow and fast harners...took about 4 hours to go off in 30 to 34oC.  Seemed to be OK.

A couple of friends helping me next week and so hope to really make some progress.  I will keep you updated. 

Thanks,

Doug

[Tim Noyce]

This looks great Doug! It's coming on nicely!

[Phil Alderson]

Looking good, is that a cunning use of peelply at the bulkhead positions, with an extra strip of reinforcement?

[Banshee Ambulance]

Looks like its going to be quick. Any thoughts on the rig? Keep us posted with pictures.

[doug1720]

Hi, I must admit that after spending so long on the mould and just getting the materials here I am really pleased to really get going.

Yes on advice from Andy I use peel ply on the mould where the bulkheads will be and put some unidirectional down under the 90 degree cloth.  (I am also planning to put unidirectional around the edges of the bulkheads when they are fitted.)

In terms of the rig I need some advice.  Mast is 2m from the end of the snout....1.7m from the stem.  I believe the current thinking is max jib and smaller main and so thinking of jib around 5.5sqm and main the remaining 10sqm.

I want to go for a stiff rig - wind here is sea breeze only 99% of the time and rarely gets above 16knots and also is the tropical breeze without the power of wind in the UK - so little reason to power off?  So thinking of two spreader.  Any advice would be good.

I am going to make my own rig and plan to use layups on the wiki.

I am on the hunt for mandrels at the moment - no B&Q here and so more difficult!

I need to design the mast and decide on forestay length, spreader positions and length - all help accepted!

I need to get some wider unidirectional that will be suitable for the rig build - any ideas on sourcing.  Also keen to get some carbon sock for the final layer?

Today I am working on the foam...I will post more pics.

Thanks,

Doug


 

[Born Slippy]

I need to get some wider unidirectional that will be suitable for the rig build - any ideas on sourcing.  Also keen to get some carbon sock for the final layer?

We used 300mm wide uni cloth for mast 2 - on a rooughly 50mm mandrel it went round just over twice (as the cloth spreads out when you tighten it in).  Not sure if would want to go more than 3 revolutions form a single bit of cloth - I'd get scarred.

I'll dig out the rest of my mandrel dimensions this weekend and post on the wiki - I think I can also try to dig up some pictures of the mandrel jig. BTW the mandrel we used for the mast was a "high pressure" plastic pipe - builders' merchant territory rather than B&Q.

[JimC]

I want to go for a stiff rig - wind here is sea breeze only 99% of the time and rarely gets above 16knots and also is the tropical breeze without the power of wind in the UK - so little reason to power off?  So thinking of two spreader.  Any advice would be good.

Are you thinking enough about gust reponse? Its a key thing for keeping the boat manageable, and these days I tend to think of it as being more important than raw power.

[ross_burkin]

Jim, you used to crew! You should know that 'gust response' is just made up rubbish and the crews arms are what really count

[doug1720]

Hi, agree that the rig needs to have some give in the tapered top section and not a tree trunk....I suppose I am explaining that because of the conditions here I will be in fully powered up mode a lot of the time and therefore eering to the tree trunk   I think in the UK I would be looking at more of a balance between power up and depower.

Is 2 spreader the way to go?

Is there any information available on forestay, shroud lengths and positing of spreaders?

Foam on the hull!

Thanks,

Doug

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