Converting from C-Flex to Cold Mould?

[CharlieCobra]

I'm considering ripping the C-Flex off "Oh Joy". I was wondering if the planks could be pulled, epoxy enfused as done when cold moulding and refastened. What, if anything, cuts 5200?

[Robert Gainer]

Cold molding is an entirely different type of construction. The solid planks if soaked in epoxy are not the same as a cold molded skin. Can you fix the bad spots and keep everything else the same?
All the best,
Robert Gainer

PS Good to see you have found this site.

[PAR]

One of the biggest problems old wooden boats encounter when attempting a 'glass sheathing of some sort, is the quality of the surface it will be asked to stick to. A dry, clean, oil and other contaminates free surface must be had or the ability of the goo (which ever is used) will be compromised. This is generally difficult to find on an old boat.

Typically old boats have layers of paint, repairs of several different types, water and oil soaked planking, questionable planking and fasteners, plus usually weakened structural elements. These are the usual conditions that bring up the discussion of sheathing a tired old boat. These are also some of the reasons sheathing old wooden boats doesn't work very well, except when the sheathing is quite thick (like yours is Charlie).

You can remove the C-Flex, but it's a tough job, especially if epoxy was used. For those not familiar, C-Flex is made of 'glass rods, lightly held together in plank form with a scrim, which is wetted out and filled. It's not especially light weight, with its main advantage being the ability to conform to compound curves, in one off applications. It requires a lot more fairing then more traditional methods too.

You may find you have a lot of planks to repair when you remove the C-Flex. Some from the removal process or from other reasons maybe some left over from the needed repairs not preformed when she got her cure all C-Flex sheathing. I'm not sure what the method (originally) is used on your boat. If it's carvel, I wouldn't recommend it have its planks epoxied. Ditto traditional double plank.

Can you post some pictures and more details about her construction?

[CharlieCobra]

I have pics of the C-Flex job but they aren't digital, just pics. She was taken down to bare wood, replanked where needed, refastened and then dried for 45 days prior to the C-Flex application. She seems very solid and other than the normal couple of inches of water in the aft bilge from packing gland seepage, she's dry. She was carvel plank (mahogany over white oak) construction with 10" rib centers.

[PAR]

The problem with most sheathing jobs, is the client rarely can wait long enough, to permit the planking to dry to optimum levels for the goo to stick well. This coupled with contaminated surfaces (in spite of aggressive sanding) usually makes for a weak bond. To counter this, a heavy sheathing is sometimes used. This tends to be more stable, a shell around a shell if you will. Other efforts include stapling the sheathing on during wetout, setting nails with their heads exposed for the goo to grab hold of, etc. All these efforts are to increase the bond on less then desirable surfaces.

Your sheathing job sounds like a pretty sound one, certainly better then most. Can you scan the pictures or have them scanned at the local Office Max/Depot and post them?

[CharlieCobra]

It may take a few days but yeah, I can scan 'em.