Crack in binder strake...

[NGrace]

Hi folks,

I have a crack in the binder strake of my "new" dory. The crack seems fairly tight and will likely seal up OK when the boat gets soaked in the next couple of weeks. There is no rot present and the wood on either side appears to be very solid. I'm concerned that the crack will continue to tavel down the plank and get worse. Is there anything I can do to stop the crack and perhaps fill it in?

Thanks in advance.

Regards,
Nathan

[Tom Robb]

What's a binder strake?

[NGrace]

The binder strake is the second plank down from the top. The crack is about a foot and a half in length.

Thanks,
Nathan

[Hughman]

What material? What thickness? Painted? any fasteners nearby? Is the plank flat sawn?

Note: If folks want vague answers, ask vague questions.

[NGrace]

The dory is pine on oak frames, the planks are 5/8" thick (I believe), I don't believe there are any fasteners near the crack, other than the rivets along the top and bottom edges. The boat is currently painted, but will soon be stripped. I believe the plank is traditionally sawn. It was made by the Lowell Boat Shop in Amesbury, MA.

Nathan

[Tom Robb]

Binder strake, Hmm. Learned something new, I guess.
How wide is the crack? If more of a split of very little or no width you could try glue. Worst case it'll split again. It'd be nice to know why it split. Some advocate drilling a very small hole at the end(s) of the split to terminate it. Since it sounds like it didn't start at a fastener, perhaps it was an hidden defect in the wood.
At least it won't sink the thing.

[NGrace]

It struck a dock or piling last year. Other than that, the boat is in super shape.

Nate

[Bob Smalser]

It depends on why it cracked.

If from collision then butter in some thickened epoxy. If a fastener split them spring the plank out and repair using epoxy. If it cracked during your dry season from seasonal movement....most common in flatsawn, wide garboard strakes...then squirt some 5200 or some other soft sealer in the crack...glued repairs will simply crack again.

[NGrace]

Hi Bob,

If I put in some West System with microfibers will that keep the crack from traveling any further, or is that just a temporary fix?

I've been reading some of your older posts. Do you refinish gun stocks as well as work on boats? You live in a great part of the country for hunting and fishing. Would love to get out there some day. I know a fellow out there who is an avid duck hunter and collector of wooden Barnegat sneakboxes.

Best,
Nathan

[Bob Smalser]

Hi Bob,

If I put in some West System with microfibers will that keep the crack from traveling any further, or is that just a temporary fix?



Permanent, unless you're wrong about the cause of the crack. Then it'll just crack again, perhaps worse with hard epoxy acting as a wedge. If this is early in your humid season I'd wait another month or more to see if the crack closes tight. If it does, then it's likely from drying out, not collision.

You want an adhesive thickener for a collision repair:


ADHESIVE FILLERS

403 Microfibers
403 Microfibers, a fine fiber blend, is used as a thickening additive with resin/hardener to create a multi-purpose adhesive, especially for bonding wood. Epoxy thickened with microfibers has good gap-filling qualities while retaining excellent wetting/penetrating capability. Color: off-white.

404 High-Density Filler
404 High-Density filler is a thickening additive developed for maximum physical properties in hardware bonding where high-cyclic loads are anticipated. It can also be used for filleting and gap filling where maximum strength is necessary. Color: off-white.

406 Colloidal Silica
406 Colloidal Silica is a thickening additive used to control the viscosity of the epoxy and prevent epoxy runoff in vertical and overhead joints. 406 is a very strong filler that creates a smooth mixture, ideal for general bonding and filleting. It is also our most versatile filler. Often used in combination with other fillers, it can be used to improve the improve strength, abrasion resistance, and consistency of fairing compounds, resulting in a tougher, smoother surface. Color: off-white.


Clean the crack and blow out with compressed air. Prop the boat so the crack is horizontal and flat. Apply masking tape as a dam over the inside of the crack.

Mix marine epoxy without thickener and brush into crack. Use a heat gun lightly at the edges to thin the epoxy and insure it seeps all the way to the ends of the crack. Mix adhesive thickener into your remaining epoxy and spatula in. Beltsand, prime and paint after curing.

Don't clamp the crack other than to line up the edges.

[NGrace]

Thanks Bob, this is great. I was told when I bought the boat that the crack was from a collision with a dock. Also, the crack is toward the front of the boat and not in the middle where I've seen other strakes crack due to movement or being turned over too many times without care. The crack seems tight right now, but it has been wet and humid here the last few weeks. I will wait another month or so to treat the crack.

If you ever find yourself out on the east coast, drop me a line and we'll do some fishing out of the old dory.

Best,
Nathan
nategrace@gmail.com