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Old Feb 01, 2013, 02:41 PM
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Marblehead build advice

Working on a Marblehead at the moment, hull and deck complete, also fin and rudder. I've got 2nd hand rigs I can use for a while once it's built. One thing I'm not sure of though - can I use a standard Futaba 3003 servo for the rudder, or do I need something a bit stronger? Any advice much appreciated.
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Old Feb 01, 2013, 02:45 PM
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On a balanced blade rudder a 3003 is fine.
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Old Feb 01, 2013, 05:29 PM
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Yes, A 3003 is fine.
I happen to use the Hitec HS-645mg for rudder servos in every single one of my boats.
It's way overkill on an M at 133oz/in, but my servo is standard on every boat I own.
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Old Feb 10, 2013, 02:32 PM
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Brilliant, thank you. Saves me buying another servo. I've got an old winch servo from an old M I bought on Ebay - all keeping costs down! Pictures of build so far attached. The dull area on the back of the hull is where I've sanded it down for the last coat of varnish.
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Old Feb 12, 2013, 05:11 PM
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Awesome!
What design is it? Is that one of those Tippecanoe T50 Marbleheads?
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Old Feb 15, 2013, 03:25 PM
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It's a studio 3 design from

http://www.nonsolovele.com/Plans&Models.shtml

It's effectively only the frames and sailplan, I chose that hull form because it looked like I could build it in hardwood. The fairly clean lines without excessive curvature allowed for traditinal planking. I'm building with a deck-stepped mast (on a sliding track) rather than the swing rig in the plan. It's not the lightest M ever, as I've gone for looks (and a traditional transom) but it's not as heavy as you would expect. Next big job is moulding the keel bulb!
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Old Feb 15, 2013, 07:05 PM
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Awesome!
Great to see someone building a Marblehead from Claudio's free plans.
Do update your photos as the build comes along.

I'm not sure if you are a member of the AMYA, but you can register with the class for $7, and join in on one of the highest-class populations in the entire AMYA
http://www.theamya.org/boats/marblehead/


Your M, design-wise is on par with alot of modern boats. If you find yourself in M.A. look me up and bring the boat!
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Old Feb 16, 2013, 12:52 AM
Kimo
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Great looking boat, hull looks very similar to the T50MOD that I am building from Tippecanoe. The T50MOD is planked with western red ceder planks without bulkheads so it is a light boat. I believe that the ready to sail T50 weighs just over two lbs, and a 5 lb bulb brings it up to required Marbelhead weight.
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Old Feb 16, 2013, 07:11 AM
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Quote:
Originally Posted by Hircsailor View Post
and a 5 lb bulb brings it up to required Marbelhead weight.
There is no required weight limit for any Marblehead.

Actually, Every Marblehead is different, and what matters is that the individual boat you are building is made to the plans set forth by the designer.
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Old Jun 03, 2013, 01:07 PM
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Another question - is cork allowed as a material for the bow bumper?
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Old Jun 03, 2013, 05:50 PM
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Not really, the rules state at least 13mm of "elastometric material"....

Cork hardens, and isn't a resilient medium. These boats can move fast, so you don't want a hard material that can cause damage to others.

Many use foam, and just sand it down to fit the bow profile, or tape card around the bow, and fill it with Sikaflex or something similar. Give it a week to cure, then you can trim it to suit. I did this on my first planked IOM.

Hope this helps....

Pat
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Old Jun 03, 2013, 06:11 PM
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Not really, the rules state at least 13mm of "elastometric material"....

Cork hardens, and isn't a resilient medium. These boats can move fast, so you don't want a hard material that can cause damage to others.

Many use foam, and just sand it down to fit the bow profile, or tape card around the bow, and fill it with Sikaflex or something similar. Give it a week to cure, then you can trim it to suit. I did this on my first planked IOM.

Hope this helps....

Pat
Is it illegal?
Who knows, and who cares.
Pay no regard to the "rules" in this aspect. Just fit a bumper from whatever looks good, and that will absorb an impact.
The point of a bumper is to avoid damage to another boat if an accident does occour.
No-one is going to battle you over rules on a bumper.....Just make sure you have one.


in regards to Cork, it's generally pretty hard even before it is hung out to dry. You want something nice and soft.
I think Balsa is the best. It's one flaw being that if you to whack something it does not come back to form. Therefore Balsa is illegal as it is not "Elastometric" but please..... Who will argue elastometricity after being stemmed by an M?
There are some good silicone bumpers, but even those dry-out and become hard.





And sail with the thought process that it's better to avoid an impact at all costs rather than find out how good your bumper is at absorbing a mis-step.
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Old Jun 03, 2013, 08:07 PM
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Actually, anyone who races Marbleheads cares about the bumper material. If you build a boat without a "soft" bumper, I personally don't want you racing with me. The bumper is a basic courtesy for other people you are sailing with-- it's really not right to have a hard, pointy nose on the front of your boat and point it at something.
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Old Jun 03, 2013, 09:51 PM
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Difference of opinion I suppose.

I care more about how the person carries themselves on the race course, rather than if they even have a bow bumper or not.
I personally have no issues or hesitations sailing an EC-12 with a sword for a bow and no bumper at all in a fleet that races properly.
And that's a spike behind 24lbs of mass.


A bow bumper isn't gonna do you much good when you get rammed at full speed sailing one sheet of Kevlar with light wood inwhales..... So maybe the concern should be more-so the inwhales rather than the elastometric bumper.

Either way. Put a bumper on your boat. Make it soft. Who cares if it's elastometric. Make it soft.
Then don't ram anyone.
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Old Jun 04, 2013, 02:37 AM
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Agree with breakwater that its important to race by the rules and avoid contact. But it is necessary that it be soft. Yes you can hole another boat if you hit hard enough, but i've seen some good hits and no damage occured. Put a hard bumper on, and the result may be different.
In racing accidents happen. Someone loses radio contact, is unsighted etc. and contact occurs. The bumper allows for this.

Make it from foam, or mould one, its not rocket science, especially after all the work planking up he boat.. Make a balsa bumper, wax it, mix up and cover it with Plasti-bond to form a mould. Squeeze some silicone or urethane in it, and let it set for a week. Pull it out, glue it on, and job done. One legal bumper....

They are there for a reason after all.....
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