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Strip: Butt joint issues?
By:Darel
Date: 12/28/2010, 10:03 pm

Hi all,

After 3 months of work I'm finally laying my first strips on a Fire Star.

I quite literally found it impossible to find full-length lumber. Local, internet, you name it. There was one possibility that would have doubled the cost of the project.

So, I decided to scarf boards together as suggested in Rob's plans. Built the jig, and also built a clamp jig to hold them square and tight while drying. Did a couple boards at an 8:1 scarf. Glued them up with TB III and let them dry for a week.

As soon as I picked them up they broke at the joints. All of them. The one that didn't break, when I ran it through the table sw each individual strip broke as it came off.

After much searching, I figured butt joints would have to do. To my (admittedly faulted) logic, the end result is the same product.

Sidebar: when I design and build things there are always compromises. As a matter of habit I generally try to turn my compromises into "design elements".

One idea I had for a design element would involve lining up all of my butt joints in a line from shear down about 4". My (admittedly faulted) logic tells me this is not a good idea for structural reasons. A little voice also tells me that most of my strength comes from glass.

Question #1: Will lining up these butt joints create a weak "seam" in the finished kayak? Like, will it break in half when I pick it up? Strap it to a car?

I laid my sheer line to see what it looked like. I like it. What I did was cut several 2" pieces of strip and (permanently) glued them to the back of the butt joint. I can either sand these off or leave them in place and glass over them. Question #2: Thoughts? Leave in place? Sand off? Will they actually do anything to reinforce the joint? I rounded off the corners so they look like little pills and I think I could live with them in the finished boat if they do actually do anything.

Like I said the line of butt joints will be from the sheer line about 4" down. There will be hardwood pinstripes running between the butt-jointed strips. No more than 3 butt joints will be lined up without a hardwood pinstripe between them. Does this help any?

Anyone have any thoughts? Bill, I know you have no issues with butt joints. Rob, it's your kayak and I know you DO have a problem with butt joints. Anyone feel like chiming in? I don't want to do anything that will compromise the integirty of my kayak.

Thank you,
Darel

Messages In This Thread

Strip: Butt joint issues?
Darel -- 12/28/2010, 10:03 pm
joints of many kinds *PIC*
Paul G. Jacobson -- 1/2/2011, 12:02 pm
Re: Strip: Butt joint issues?
Fred Gasper -- 12/30/2010, 7:57 am
Re: Strip: Butt joint issues?
Paul G. Jacobson -- 12/30/2010, 11:54 am
Re: Strip: Butt joint issues?
G New -- 12/29/2010, 8:07 pm
Re: Strip: Butt joint issues?
Eric -- 12/29/2010, 7:14 pm
Re: Strip: Butt joint issues?
Rob Macks / Laughing Loon CC&K -- 12/29/2010, 2:16 pm
Re: Strip: Butt joint issues?
Dean -- 12/29/2010, 12:40 pm
Re: Strip: Butt joint issues?
Joy -- 12/29/2010, 9:43 am
Butt joints NOT over forms are bad
Paul G. Jacobson -- 12/29/2010, 1:43 pm
Re: Butt joints NOT over forms are bad
Al Edie -- 12/30/2010, 12:06 pm
Re: Butt joints NOT over forms are bad
Bill Hamm -- 12/30/2010, 1:48 pm
Re: Butt joints NOT over forms are bad
Bill Hamm -- 12/29/2010, 3:02 pm
Re: Strip: Butt joint issues?
Randy Echtinaw -- 12/29/2010, 10:56 am
Re: Strip: Butt joint issues? *PIC*
Joy -- 12/29/2010, 10:09 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:28 am
Butt joint boards or strips? *PIC*
Jay Babina -- 12/29/2010, 8:19 am
Re: Butt joint boards or strips?
Bill Hamm -- 12/29/2010, 8:30 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:07 am
Re: Strip: Butt joint issues?
Les Cheeseman -- 12/29/2010, 5:03 am
Re: Strip: Butt joint issues?
Randy Echtinaw -- 12/29/2010, 7:00 am
Re: Strip: Butt joint issues?
Darel -- 12/29/2010, 5:36 am
Still got that bottle of glue?
Paul G. Jacobson -- 12/31/2010, 7:22 am
Re: Still got that bottle of glue?
Darel -- 12/31/2010, 11:31 am
buy new glue
Paul G. Jacobson -- 12/29/2010, 4:27 am
Re: Strip: Butt joint issues?
Dave Houser -- 12/29/2010, 12:46 am
Re: Strip: Butt joint issues?
JohnK -- 12/29/2010, 2:23 am
Re: Strip: Butt joint issues?
Charlie -- 12/28/2010, 11:20 pm
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:16 am
Re: Strip: Butt joint issues?
Allan -- 12/28/2010, 10:36 pm
Re: Strip: Butt joint issues?
Stephen Troy -- 12/28/2010, 10:13 pm
Re: Strip: Butt joint issues? *NM* *PIC*
Darel -- 12/29/2010, 12:43 am
Re: Strip: Butt joint issues?
Bill Hamm -- 12/29/2010, 8:33 am
Re: Strip: Butt joint issues?
mark j -- 12/28/2010, 11:19 pm
Re: Strip: Butt joint issues?
Darel -- 12/28/2010, 10:22 pm