Kingboard

[ion barnes]

I am curious about using Kingboard or Starboard as a replacment material for a rudder blade or daggerboard. Opinions?

[westinghouse]

Oddly enough, Colleen just accidently ordered some oversize stock in that might be perfect. The kicker is fastening ballast, I don't know how you'd do that. Otherwise the stuff's perfect, dimensional stability, low friction. . .

Some of your eight footers with a sailing rig would be a hot item.

Eli (at All Bay)

[ion barnes]

Just what I needed for Sunday morning, a good belly laugh. Eli, I will talk to you soon.

My concern is the material's flexability (3/4") with pressure. 3/4 ply is stiff, 1/2 ply with glass is stiff too, but the Kingboard, all that I would do is machne the edges and a cap on top.

[pipefitter]

King Board is pretty flexible and heavy as well. I just dislike the stuff. Alot of people replace the wood on their boats with it here. If I use it I always have to use strong backs and stiffeners of the same material? It seems as flexible edgeways too. That and the mess it makes when cutting it or machining it is pretty big too.

[westinghouse]

smile.gif I'll have a look at the stuff on Tuesday, she brought in a couple of different thicknesses. I agree with what pipefitter says and I don't think it'd be great for a dagger board, but something like a Haven's wedge shaped center board might be okay.

Hope your feeling better,
Eli

[pipefitter]

The stuff really scratches easily too and it ends up looking like a well used,stained cutting board in the kitchen.Doesn't sand worth a damn and you have to use a scraper on the edges.It will clog a belt sander's paper in one pass.Only way to really do it is with a router and carbides.

[ion barnes]

Pipefitter; What thickness are you refering to? I was concidering 3/4" - 36" X 12"

[pipefitter]

The 3/4 is flexible too. We have sheets standing almost verticle leaning against a wall and it gets a sag in it standing there.It is just uniformily flexible throughout. Atleast with Plywood there is layers of alternating grains to stiffen it. I think the density has much to do with it because we Have this poly sheet that we use for upholstery backing and it seems to stay flat yet is alot lighter.They use it for console doors and they have to use 2 latches to hold it shut evenly in the opening.I wouldn't use it with a force of water on it. Then again,I dont know what load is on it for what your application is.I am just stating that it isnt much good from what I have seen unless it is mounted on something rigid.It may work great for what you need. I just dont care for the stuff.
36x12 will flex alot in that 36".I dont know how much of it would be exposed to load for your use.It makes nice instrument panels in modern boats or drink holders,things like that.When used for doors and things it relies on the piano hinge for stiffness when it is open and the door frame when closed.

[ 04-19-2005, 03:11 AM: Message edited by: pipefitter ]

[ion barnes]

Thats the detail I wanted! It looked like it had possibilities. Thanks pipefitter.

[Keith Wilson]

If you do decide that it's stiff enough, (and I'd bet it isn't) you could add ballast by using lead shot in epoxy. Cut a hole like you'd do for poured lead, back it up with something that won't stick, drive some nails partway into the edge of the hole to give it something to hold on to, fill the hole with lead shot, then pour on epoxy. It won't exotherm because the lead shot is a good heat sink. You'll probably need less ballast than with wood because the plastic is denser.

[Tom Robb]

What the hell is kingboard? :confused:

[ion barnes]

aka 'Starboard' Plastic board something like the stuff for cutting boards, advert as an alternative for wood trim etc. Look in West Marine catologe.

[Tom Robb]

Oh... Since I seldom do West Marine, I'd not seen or heard of it.
Thanks.