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On 9/29/2017 at 11:10 AM, Dex Sawash said:

I need to change a few things on my Nethercott.

Boom blocks are currently attached to swaged wire loops wrapped around piece of glass laminate that floats on oval aluminum boom. Inelegant and the wire is degrading the glass and it will fall apart soon. What is standard boom block mounting practice now?

BTW, I have a carbon sweep oar that would probably serve as a boom but would need to sort out a gooseneck fitting for the tube somehow (gooseneck fixed on deck post now)

Will 3/16" jib sheets work ok in higher winds? All jib turning points have fairleads now and 7mm sheet does not run free enough in the very light air I have been sailing in (no dangle pole or jib boom fitted)

David uses Carbon sweep oars for a bunch of his boats. It's about as strong a carbon shaft as you'll find. Goose neck - I think he just shoved a steel bar in the thick end with a fitting on it. He can say more though.

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No minimum boom dimension?

 

Quote

The boom excluding fittings shall be capable of passing 
through a circular hole of 100mm diameter. A boom used for the 
foresail excluding fittings shall be capable of passing through a 
circular hole of 30mm diameter. For wishbone booms used for mainsail 
and/or foresail each side of a wishbone shall be measured separately 
and shall comply with the same limits.
 

 

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On 3/10/2017 at 3:46 PM, chrishampe said:

Well I will go with the 2.5mm rod, I will leave the swedging to the boys at the local riggers. Apparently there is a special technique that they are a bit hush about, but they have a great reputation. Harken Ha300 1" wire blocks should be strong enough to run the high load end of the shroud adjustment. Need to get the rig up to measure the fore triangle so I can pass all the measurements on to Frank Rowsell to make the sails. His lead time will more than likely dictate when I launch.

 

Chris H

Probably want to upsize those wire blocks. I think 1.5" were the smallest ones that did not eat themselves. Bill Beaver lost his rig that way on Arrested Development at 1996 worlds. Julian Bethwaite came cruising through the dinghy park early in the regatta, had one look at his 1" wire blocks and said "Oh - that will never hold." Bill had done the math, and was sure it would hold. Sure enough, it didn't. No one came to get him after the rig failure, because a storm had wiped out the whole fleet, so he managed to restep the mast on the water with a bit of string on the end of the shroud, and got back that way. A size up is cheap insurance.

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Just about to re-build a new set of chainplates for MCR (yeah, should have done that when I scooped out the fore-deck to move the carriage tracks forward and re-painted the hull), a little (25mm) further aft and will create a small winglet to save me having to remove the deck again. 

From the brains trust, is a 3/16 pin best option or make it 1/4 inch to be bullet proof? 

 

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3/16ths will hack it as long as the span is really short, like under 5mm. If wider, best go with 1/4 inch.

SHC

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22 hours ago, Steve Clark said:

3/16ths will hack it as long as the span is really short, like under 5mm. If wider, best go with 1/4 inch.

SHC

thanks Steve 

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Is there a generally accepted hull shape which is suitable for us fat bottomed and more lardy types ( about 100kg ), thanks

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https://www.facebook.com/groups/sail.ic/permalink/10155763615948422/

Simon putting his self completed Maas Super String Theory though some paces.  He should have some more vang on to limit how much twist he gets when he dumps sheet.  This will modulate the rolling.  Nice look isn't it?

Not Foiling, ICs don't do that, but not many monohulls do this either.

Wayne, the 100 kg isn't a problem,  the "lardiness" may be.  There are many big boys sailing in the IC fleet, on different designs. The long narrow hull carries weight without many of the negatives of shorter fatter boats. But, a level of fitness and ability is required to react fast enough when things get interesting.

SHC

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2 minutes ago, Steve Clark said:

https://www.facebook.com/groups/sail.ic/permalink/10155763615948422/

Simon putting his self completed Maas Super String Theory though some paces.  

Not Foiling, ICs don't do that, but not many monohulls do this either.

Wayne, the 100 kg isn't a problem,  the "lardiness" may be.  There are many big boys sailing in the IC fleet, on different designs. The long narrow hull carries weight without many of the negatives of shorter fatter boats. But, a level of fitness and ability is required to react fast enough when things get interesting.

SHC

I got weighted at the doctor the other day. I hadn't been on a scale in over a year.
227 lbs. That's almost 103 kg haha.

The first time I sailed an IC it was one of your DC boats--in 6 knots with Dave in the dory coaching. Now that I've been sailing Matilda for 3 years, I wonder if it is time to see what happens if I try to stay upright on 700 mm again...I suspect I'd do fine until I'm tired...

 

But on the question of weight versus hull form of course I've thought there might be something there and yet as with all dinghies because we can trim them with ourweight, perhaps it really isn't so needed. If one were to build a bit wider, that would simply be a speed penalty all the time.

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Deliberating that now, realistically I will not be under 100kg in the near future and am sailing one of the tortured ply IC's in AUS without too many issues. It is time to start building new boats for the next worlds scheduled for December 2020 so am in that middle ground, I love the look of Geoff's MCR V2 drawings, the Machete is the easy option with another being built here at the moment or go for something well proven.

MCR is now a bit overweight (but will survive another 10 years of abuse), was definitely not the fastest boat at the nationals we sailed last week.

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Not the fastest.... but fast enough to win everything and more easily handled in the heavy stuff.

 

I want to know more about the "Gentleman's IC" from Centre Island.... I could be a gentleman one day, if I tried hard perhaps....

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Brett and others who may wish to build the Machete hull shape out of foam and carbon or some other method other than the CNC cut plywood kits.  I have prepared a CNC cut file for external forms into which pre laminated panels or foam sheets can be placed and taped together.

SHC

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Steve, was a mould taken from/for Bagheera? Was the boat at Wales I thought would be most marketable to fleet build from.

I asked David a while back for a hull/carriage/seat/foils price and I think he did make a quote, but never made it to my inbox and was/is low on his priority list understandably.

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1 hour ago, brett221 said:

Steve, was a mould taken from/for Bagheera? Was the boat at Wales I thought would be most marketable to fleet build from.

I asked David a while back for a hull/carriage/seat/foils price and I think he did make a quote, but never made it to my inbox and was/is low on his priority list understandably.

No mold was taken as we satisfied all the demand with the first two boats.

I quoted the whole thing out and sent it but I'll resend it. It came out to $23606 USD per bare hull ready for hardware and other parts. 

Keep home building. Building ICs is fun amd racing them is even more fun. But an IC is not a commercially viable product.

DRC

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Hi Guy's,

 

I have a question with respect to the foils the canoes use so would appreciate any help.

 

Centre Board, I have seen that some boards taper aft (Straight trailing edge) as you get towards the bottom & some taper forward (Straight leading edge), is there any benefit form one way or the other in Canoes? (I was looking at using an A Cat profile)

 

With the rudders, I see that they are stern hung on the newer boats, is this mostly due to the benefit of having the tiller further aft for manoeuvres or is the advantage of not having a surface penetrating foil not as great compared to the Nethercotts?

Thanks

 

Geoff

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I think with the rudder, getting your body further back in the bus is the major factor as bows get narrower, centreboard question is well above my iq, have used both and both work.

 

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Ah the old foil debate.... I have a straight leading edge on the daggerboard but no difference as far as I can tell with having a straight trailing edge... section is important, but not sure whats best, mine's a very conservative NACA 0010. cord is 220mm a bit wider than some but I've chopped 100mm (I think) off the bottom, 200mm cord seems good and those are run full depth. Rudder is transom hung, the theory with the cassette rudders was that the boat acted as an endplate but the pins always bent and it all ended up being heavier and more difficult to build, also as bret says we all sail much further back in the boats now. My rudder section is NACA0012, cord I think is 120mm but I would have to check that and it sticks some 600mm below the line of the bottom of the boat.

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Is converting a Nethercott to a transom rudder a worthwhile project? Beach launch is a bit of a faff, wading out worrying about losing both the rudder and the dagger. Seems a transom rudder casette could be a convenience upgrade. 

 

 

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The key trick is to put the rudder into the tru;k, but don’t push it down. This makes things pretty easy. You can actually steer a bit, and the whole mess will pop out if you ground or hit anything. Over the years I have found this as easy as anything else.

SHC

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5 hours ago, Steve Clark said:

The key trick is to put the rudder into the tru;k, but don’t push it down. This makes things pretty easy. You can actually steer a bit, and the whole mess will pop out if you ground or hit anything. Over the years I have found this as easy as anything else.

SHC

Thanks, will give that a try.

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ÏWife was watching beachfront bargain hunt, they were looking at houses on Dauphin Island and this boat was in it.

 

20180819_200506.jpg

 

Any ideas?

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3 hours ago, Dex Sawash said:

ÏWife was watching beachfront bargain hunt, they were looking at houses on Dauphin Island and this boat was in it.

 

20180819_200506.jpg

 

Any ideas?

Looks like a Waszp to me

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16 minutes ago, FishAintBiting said:

Blind??

Never seen a DC nor an IC?

Big hit to the head?

Some of each. 

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Another advantage of the trunk rudder is that you don't have to go nearly so far aft to put it in. If you are a "more substantial" sailor then the extra foot or so means the stern sinks a fair amount under you, which in turn means you don't need to be in such deep water to put it in or take it out.  Alternatively, if you put the rudder on before climbing on the boat, not having to go so far back makes it easier to keep the bow into the wind.

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On ‎8‎/‎6‎/‎2018 at 1:17 PM, Harnser said:

Ah the old foil debate.... I have a straight leading edge on the daggerboard but no difference as far as I can tell with having a straight trailing edge... section is important, but not sure whats best, mine's a very conservative NACA 0010. cord is 220mm a bit wider than some but I've chopped 100mm (I think) off the bottom, 200mm cord seems good and those are run full depth. Rudder is transom hung, the theory with the cassette rudders was that the boat acted as an endplate but the pins always bent and it all ended up being heavier and more difficult to build, also as bret says we all sail much further back in the boats now. My rudder section is NACA0012, cord I think is 120mm but I would have to check that and it sticks some 600mm below the line of the bottom of the boat.

My rudder is 130mm cord (when I actually measured the CAD). For my next set I've a mind to have the max thickness straight and curve both leading and trailing edges as it tapers, that's if it ever gets off the CAD and into real world... Been playing with some bits in the garage, first time in about 3 years, looking at making some tubes for spars. Can't get any longer than a boom until the bedroom furniture is out, oh and the multiple washing machines etc....need to get a skip!

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17 minutes ago, Harnser said:

My rudder is 130mm cord (when I actually measured the CAD). For my next set I've a mind to have the max thickness straight and curve both leading and trailing edges as it tapers, that's if it ever gets off the CAD and into real world... Been playing with some bits in the garage, first time in about 3 years, looking at making some tubes for spars. Can't get any longer than a boom until the bedroom furniture is out, oh and the multiple washing machines etc....need to get a skip!

That'll cost you now the council have put the charges up on the tips.. 60,000 less visits to the tip this year since they did that.. more dumped rubbish..

 

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