Cove and Bead Strips from Plywood

[Daniel Huckleberry]

Joel or anyone else who would care to comment,

I am planning a build that requires 0.75" x 1.0" cove and bead strips, 16' to 17' long if I do solid wood with no joints. I am interested in the idea of scarfs/puzzle joints cut by the CNC machine in 3/4" ply. I could then glue them up at home before "planking" the hull. I don't think the puzzle will work as there is not enough gluing area introduced when the strips are cut down to 1' wide. Can BBC cut a scarf taper on the plywood that I could then rip down into say 7" wide pieces, glue up, then cut into strips and mold cove and bead? I am open to any other suggestions you may have including complete molding on the CNC machine.

Thanks and Happy New Year,

Huck

[tech_support]

Hi Huck, nice to hear from you. I dont think the puzzle joints will work for making a panel that will then be ripped into narrow strips. A scarf would be the way to go, either that or a couple of "steps" routed onto each edge. I know we could write a cut file to make the steps, but it would be a little tricky as the Z plane would have to be super accurate. If you have a router, it would probably not bee too difficult to do them yourself.

[jacquesmm]

We don't scarph and can not cut bead and cove strips, sorry.
As Joel wrote, we could do a step scarph but
- I don't see the need for it and
- I don't know how we would ship it without damaging the edge.
I can't guarantee a perfect match of the steps.

If you do bead and cove, the strips do not have to be full length, you stagger the joints.
You could cut your own strips from our plywood, 8' long then route the bead and cove sides.

[Daniel Huckleberry]

Thanks for the responses. I had already looked into building a jig for my router or skilsaw so that is what I'll do. I just thought that IF your CNC table was set up for it it would be clean and perfect. I do understand the potential shipping damages and the same had crossed my mind.

I am going to scarf the panels or pay for solid wood because this is a short boat with lots of curves and twists so I believe it will be easier to keep fair if I do it in one piece.

Happy new year to all and if I decide to not build this skiff, it will be a FS14.

Huck

[pee wee]

I'm not making a recommendation, only posing the question- what about a finger joint router bit? They use them to make up paint grade moldings, seems like they would work on plywood, also. The joint wouldn't be as strong as a scarf joint, but maybe using epoxy for the glue it would be strong enough to take the bending required?

[Daniel Huckleberry]

My guess is that it would not be strong enough. Once you cut the ply into strips the glue joint is reduced to a very small area which is why it requires so much material to scarf.

Thanks for the ideas.

Huck