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HarryH
10-26-2004, 05:39 PM
Would like to be informed by the guys who have successfully stip built using the convex/concave strip building technique. The design of my 23' calls for 13/16" sq. strips which need to be beveled, the most severe of which is at the turn of the bilge where the gaps between strips would otherwise be 1/8"+ or so. I will be using edge nailing, and glue other than epoxy, so they need to be fitted.

The designer did mention, before he passed away, that some of the guys used a cutter somewhat shaped like a bathing beauty (!) on the strips to avoid planing fits. I assume this is simply a couple of passes, to get one edge convex, the other concave. I am guessing this is somewhat wasteful of material, so should I rip the strips larger initially? I guess the concave cutter should not run out to the edge of the 'plank' to avoid a splintering edge? What about square strips where the bevel is modest or nearly non-existent, and go for the bead/cove elsewhere?

Finally, any tips for keeping the inside of the hull somewhat free of glue? I am thinking applying a ceiling is going to be inevitable otherwise..

Much thanks,

Harry

Venchka
10-26-2004, 06:01 PM
Originally posted by HarryH:
...

I will be using edge nailing, and glue other than epoxy, so they need to be fitted.
...
Finally, any tips for keeping the inside of the hull somewhat free of glue? I am thinking applying a ceiling is going to be inevitable otherwise..

Much thanks,

HarryWhat is the design? Size? Use?

Why not epoxy? What are you thinking of using in place of epoxy?

As for the inside of the hull and glue drips-will it be possible to get to the inside surfaces as the strips are applied and clean up the drips with whatever solvent the glue manufacturer suggests? This seems like another reason to use epoxy as the excess can be trimmed with a knife while the epoxy is still green-rubbery but not hard. Or, a heat gun can be used to soften the epoxy once it has set and cut off with a knife.

Wayne
In the Swamp. :D

HarryH
10-26-2004, 07:33 PM
Design is Downeast ala lobster boat, w/similar lines, tumblehome, sheer. It will come out of the water in the winter. As stated, length is 23'. Beam is a tad under 8'.

I prefer resorcinol and decent fits if possible as opposed to googe and gaps, although I am far from an ivory-tower purist. Just my preference.

-H

Bruce Hooke
10-26-2004, 08:19 PM
Are you aware of the recommended clamping pressures for Resorcinol? They are much higher than anything you are likely to achieve with nails or even light clamps.

One source I checked recommended 100 PSI for softwoods and 200 PSI for hardwoods when gluing with Resorcinol.

alteran
10-26-2004, 10:04 PM
There is a fantastic website on the net that addresses strip making in great detail. I read it last night and now cannot find it. Originally I found it with google. I think. Gives lots of good tips about sawing them out with a gang saw, planing to uniform thickeness after sawing, making the bead and cove,using a heat gun to help bend them on sharp curves, how to strip to reduce fairing and sanding to a minimum....

Great site. Hope you find it. If I do I'll post it for you.

--------------------

I FOUND IT!

http://www.michneboat.com/Making%20Strips.htm

http://www.michneboat.com/Builder's%20Corner.htm

http://www.laughingloon.com/shop.tips.html

And also look at this site of links. Lots of good info here.

http://www.home.earthlink.net/~durgerian/id15.html

Al.

[ 10-26-2004, 11:18 PM: Message edited by: alteran ]

RonW
10-27-2004, 01:22 AM
http://www.sredmond.com/strip_plank.htm

Harry- check this out,read it twice and slowly, there are a lot of fine points that can be missed.

HarryH
10-27-2004, 09:34 AM
Thanks Bruce...alteran..RonW,

I have used Resorcinol with some success, and yes it sure likes to be clamped. Diagonally edge nailed every 6" or so would tighten strips up plenty to give a good joint, according to builders notes, and I can see that. (Strips are 13/16" sq.) I am not locked into resorcinol either; I read Mr. Pulsifer of Pulsifer-Hampton boats uses 5200, but if that squeezes out of joints you've got a heck of a mess not suited to easy sanding. Expense, working life, strength in service all play in, and I am sure open to comments.

TimothyB
10-28-2004, 12:46 PM
You could just use Steve Redmond's described 'Traditional' method.. no adhesive at all, just a layer of thick paint. I would put a thread of cotton caulking soaked in white lead between the planks myself, painted over sloppily with oil paint so everything gets soaked with paint before driving home the nails.

--T

JimConlin
10-28-2004, 05:09 PM
A few random thoughts-

I'm now building a boat which is strip planked and has glass structural skins. While there are other structural members of wood, the strip planking material is not. I used cove & bead edges formed with bullnose and core-box router bits from MLCS (http://www.mlcswoodworking.com/) . The cove&bead strips engaged their neighbors and self-aligned to a surprising degree. I found it useful to vary the width of the strips to accommodate the changing curvature of the hull. I occasionally introduced a spiled strip to straighten things out and avoid significant edge-setting. As edge-setting was minimal, I could get away with strips which were fairly wide, minimum 2.5x thickness (5/8") and frequently 6x or wider. The adhesive between the strips is light epoxy bog. It can be pretty light and still be as strong as the planking material. Experiment! The lighter it is, the easier it is to sand off. After fairing and glassing the accessible side and removal of the hull from the setup, the messy side was attacked with a scraper and a soft-pad sander. For wood planking material, a heat gun might be the right tool here.

Hope this helps,
Jim