Gluing a strip canoe with a "wood welder"

John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

I am new to this forum but have been reading it for 6 months - it is a great resource! I started my first build, a Bob's Special, after Christmas 2009. I have used a WorkRite RF gluer in my shop for many years and was really looking forward to use it to build a canoe, now I don't know how I could do it with out it. You zap the strip several times down it's length and it's done - the glue is cured - no waiting for glue to dry. You can lay up as many strips as you want (or can) in a day or evening. I used white cedar which is light in weight and color but the lengths are 8 to 9 foot. I didn't want to use a lot of short lengths with butt joints so I opted for all scarf joints. Each strip had at least one joint and some had as many as four to avoid joints being close to each other. After a quick zap at each joint I had a 16 footer - it worked great. See http//tinyurl.com/JB-scanoe.

mbolton · Joined: 14 Jan 2006 Posts: 43 Location: Michigan

Nice! But those baby's aren't cheap are they? I'm guessing you must do some professional woodworking?

Aljo · Joined: 03 Jan 2010 Posts: 6

Hi John, the url you posted doesn't seem to work, could you pleas check it, I would really like to see the pics. Thanks, Aljo

John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

They aren't cheap, but they are available used, a friend just picked one up for around $500. I was in the architectural woodwork business for 25 years and in retirement I've been doing cabinet and furniture work for another 16.

John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

Here's the long version URL, maybe it will work better. http://picasaweb.google.com/momamdpopb/JBSCanoe?authkey=Gv1sRgCMnF9becj8XPbw#5432946127676028482

Aljo · Joined: 03 Jan 2010 Posts: 6

Thanks, now I can see...so it is a RF welder which with the use of rf wawes cures the glue quickly if I understand correctly?
Nice tool for sure!

John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

That's right, kind of like a microwave.

John

Tom in MN · Joined: 22 Feb 2005 Posts: 162 Location: Eagan, MN

John,

I looked at your pictures. Couple of questions?

You made your scarfs as a miter, while most scarfs that I have seen are cut across the face of the strip or board, which I believe would technically be a bevel. With your method, it seems that you now have a joint that is 4-5 inches long, vs a joint that is only as long as the width of the strip with a bevel scarf or butt joint. Regardless of joining methods, you still have visible seam, why not make it as small as possible? Thinking

second, you surface sanded your boards after planing, then you bead and coved your strips. The bead and cove machining would completely undo any benefit of surface sanding as you are removing the face of the board (edge of the strip) Thinking

. Am I missing the benefit of the extra step of surface sanding? Seems like a lot of time, energy,wear and tear and sawdust for no reason.

Jim Dodd · Joined: 09 Feb 2006 Posts: 266 Location: Iowa

Hi John
Nice ideas ! I also like your clamping system.
Do you use regular glue, or is it specifically made for this process?
Jim
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John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

Tom - the lumber was one inch thick rough and the sanding was just the last step to insure a constant thicknes thus a constant width to the strips.

There is a specialty RF glue but the Original Titebond works fine also.

pyrofly73 · Joined: 30 Nov 2009 Posts: 30

wouldn't the scarfs end up this way if the lumber was scarfed prior to it being ripped into strips. Meaning one big scarf as opposed to lots of little ones? Is that even a good thing to do?
Xavier

John Brice · Joined: 20 Oct 2009 Posts: 35 Location: Oxford, Michian

If you scarfed the boards before ripping the joints would all be in pretty much the same place on the hull which you wouldn't want.

Tom in MN · Joined: 22 Feb 2005 Posts: 162 Location: Eagan, MN

It depends on how long your boards are. If you have some extra length, you could stagger the scarfs between stations and leave the rest overhanging the stems where they get trimmed anyway. If you cut a miter across the board before ripping, that would leave you with a bevel on the cut strip. Interesting. My initial thought would be the pointed edge would get banged up in the milling and handling of the strip prior to putting it on the canoe. If you cut a bevel on your board before ripping, then you have a miter on the strip. Either way may be a more efficient way of scarfing than making individual cuts on each strip. I may have to try this with a small board, then rip strips and see if it works.

Also, your cut would have to be a perfect 45 degress so the two strips would mate together.

Glen Smith · Posted: Fri Feb 05, 2010 3:38 pm Post subject:

I have read of some builders scarfing boards before ripping the strips. They usually make a scarf angle of anywhere from 7 to 1 all the way up to 12 to 1.
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BradRob · Joined: 26 Jan 2008 Posts: 65 Location: Grayling, Mich.

Hi John, nice looking craft. I see you are in michigan. Were did you get the white cedar. I live in grayling and i would be interested in getting some white cedar for some future builds.

I have scarfed and glued boards up to 2.5 inches in width and then ripped them into strips, never having a problem with stacking scarfs one on top of the other. I have also done the the rip and scarf method which to me is a little more work than neccesay just more awkward in handling long strips in the shop. Each way has its benefits and shortcomings.

I will have to look into that wood welder idea, it is intriuging.

Good job John.
Brad