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6ft Skiff

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JimC View Drop Down
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Topic: 6ft Skiff
    Posted: 13 Mar 06 at 10:32am
I think you're going the wrong way on hull shapes boys. I don't think you can afford to lose that much buoyancy in having a fine bow like that. At least some of the original 6 footers were really scows, but with a pseudo vertical bow cut in. Imagine a mirror, but with instead of a flat bow transom, the bow transom in two parts at an angle of thirty degrees or so. Kinda like this, but I haven't done any sums or anything for buoyancy. maybe you could get away with less rocker.



If I could be arsed I'd build one, I've got a 84 rules Cherub rig complete wth a decent pole kite.

Oh yes, are you going to have a minimum crew weight rule? I'd suggest something really silly like 30 stone so you can have two fat or three skinny crew. Underweight to be carried in bags of sand which can be tacked from side to side but must make it to the end of the race.



Edited by JimC
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Tornado_ALIVE View Drop Down
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Post Options Post Options   Quote Tornado_ALIVE Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 10:53am
How about a 6 foot uni-rigged foiler......
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Chris 249 View Drop Down
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Post Options Post Options   Quote Chris 249 Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 11:09am
Jim is right, maximum buoyancy was (historically) the way to go for 6s and 8s. Some of them were wider than they were long. The bowsprit had to be in the water to provide longitudinal stability (in a similar fashion, in Hysterical 18s you can't just ease the main in a gust or the jib on the long bowsprit will make the boat bear away and the race will be over). I have the lines of a top-class old 8 but I dunno how to post them and it's a very old boat.

Paul N's boats were very very small singlehanders, though, more like boards. Considering the way a 2.2m FW board goes with 12.5m of rag, despite the class limit of 1m beam, a rule banning boards should be brought in if you want to keep the class as it is conceived. There are top board designers who reckon a 6' by 4' board would FLY in 10 knots+. "Fly" as in, beat foiler Moths and 49ers. The Hysterical 18s, bless them, thunder/power/trundle along at probably about Flying 15 pace in such conditions so a 6' board would dismantle the 6' Skiff fleet.

The Historical Skiff Sailing Association guys (find them through their website) will be able to pass on Paul N's contact details, I think.


Edited by Chris 249
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JimC View Drop Down
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 11:47am
There'y' go boys, that's the rig I have...



(rescaled slightly)

Edited by JimC
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andy_cherub View Drop Down
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Post Options Post Options   Quote andy_cherub Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 12:59pm

Stu mate - if we are gona build this I reckon on a furler jib like THIS!!   But also longer wheelie bars are needed!

-12ft skiff, Team 'CST Composites'
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Isis View Drop Down
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Post Options Post Options   Quote Isis Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 2:23pm

Loads off comments so if i miss replying to a few shout at me and il come back to you...

No reason why scows should be banned... although the current ruleset seems to sduggest otherwise. The intension of having a vertical section on the stem was to limit snouts being used to increase LWL (banning them altogether was decided against) but the wording needs to be updated to allow for scows ideally.

The historic sixers were 6' long 6'6" wide saucer type things going for maximum volume but they were a lot heavier and carried 3 crew... initial calcs only but I think I can get away with a far finer entry with respect to overall volume (but will suffer with not having enough of that volume up front) My design on the website is a 'look pretty' kinda thing rather than a 'be fast' or even 'sailable' type thing... ive got 2 designs in process at the mo with one a lot closer to the original style and it is slowly becomming more scow-like with a lot more volume up front but the ussue there is that these things will be incredibly pitch-sensitive and if you stuff the bows of a scow under you're screwed, a finner bow and you might survive

Thanks for doing the pics Jim... another new perspective on things although you might need to resize a bit... my sketch on the last page is to scale using my 97cherub spars (boom longer than hull) Good luck flying a pole kite too! 

Turnturtle: loving the names!

Tornado_Alive: Nothing CURRENTLY in the rules to prevent you building a foiler but only because we decided the foilbase would be far to short to be practical. I have nothing against foils (I sail a moth and after the cherub mods are finished ill probibly look at foiling myself) but i dont think they have a place here if im honest.



Edited by Isis
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JimC View Drop Down
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 4:02pm
Two question on rules...

1) I mentioned earlier weight limits on crew. Are you planning a minimum? It would make it a lot moe comical if boats had to be at least two handers...

2) Real skiffs don't have sail numbers, just an individual symbol for each boat...


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Post Options Post Options   Quote Strawberry Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 4:37pm
OK guys, firstly I would like to thank everyone for the interest and support in the class which you are all showing at such an early stage. 38 replies and over 1000 views already.

Secondly I would like to apologise for for the lack of input into this thread by myself. I have jotted down some bullit points of issues which have been mentioned so far, and will try to address some of them now.

Windsurfers - I would expect a 6ft surf board to be MUCH faster than a 6ft "skiff". I don't believe this to be compatible with the class ethos, and would therefore push for these to be explicitly excluded by the rules. Have just scanned through the Moth rules and couldn't find the rule regarding windsurfers there, I'm sure I've missed it, but ran out of patience looking. Maybe someone could point it out for me?

T-foils - Again, I'm sure it would be fast to put a skiff on hydrofoils, Moth stylee. But as before I do not think this would be in the best interests of the class. However, a t-foil rudder would help greatly with fore/aft stability. I would suggest that to avoid boats being capable of fully foiling, the rules stipulate that only one horizontal foil should be used, ie. on either the rudder OR the c/b. Further to this, I would like to see a rule which makes it illegal to adjust the angle of attack of the horizontal foil. The reason for this is that it requires some complicated engineering to adjust the foil on the water, and this will greatly complicate the build of such a simple boat. I think the best compromise is to allow the use of a t-foil rudder, but it must be in a fixed position, as on the "conventional" Moths. Any views on this?

"Scow" shaped hulls -

Originally posted by isis

No reason why scows should be banned... although the current ruleset seems to sduggest otherwise. The intension of having a vertical section on the stem was to limit snouts being used to increase LWL (banning them altogether was decided against) but the wording needs to be updated to allow for scows ideally.


Ben, I agree entirely. The intention of the rule is to prevent a buoyant "snout" being used to increase waterline length. I don't see a problem with scow shaped hulls. Maybe this is a rule which needs some re-wording.

Sail numbers - I agree with you Jim, totally unnecasary and against the class principle of being a true "skiff".

Min crew - I would not support a rule which limited the weight of crew which must be on board. I would not like to isolate particually heavy/light people. Also, I cannot think of another class where crew numbers are not limited, and in the future this could be an interesting area of development in the class.

As for the mysterious "Paul N", can someone suggest where I even start looking to contact the fella? Is he Australian? Connected with the Historic Skiff Sailing Society?

To those who have already begun developing their own concepts:
It must be worth putting it into practice, what have you got to loose!


Edited by Strawberry
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tickel View Drop Down
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Post Options Post Options   Quote tickel Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 4:45pm
All this is very interesting and rather technical but it seems to me that a wide scow with a rib  like a full keel running underneath terminating in the rudder might make the thing feel longer,  This rib would be verticle at the bow. The foredeck  would be triangular in section  and stuck on top full of bouyancy, in the event of nosedive. Or how about a foiler with with the foil 1ft behind the stem. The mast would be towards the back of the boat and the only sail  is just a  big jib, loose footed and held on a bowsprit. Downwind you slacken rig tension. I did consider 2 masts and 2 jibs overlapping .Or a single mast with a "swing rig"? Or  square rigger with fixed camber?      I had better go now the nurse is coming with the syringe. If you epoxy three cornish pasties together and get some pasta you coul................................
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Post Options Post Options   Quote Bobbins Quote  Post ReplyReply Direct Link To This Post Posted: 13 Mar 06 at 6:03pm
What are you planning on making these hulls out of?  Admittedly my boat building knowledge is close to zero, but making some of the flat-nosed hull shapes out of ply and on a student budget looks like something of a challenge. Can't see how you could keep the wood stressed like in some of the moth designs
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