sheena's dad said:
If you don't mind, I'd be real interested in seeing some plans for that.
In case anyone is interested, here's a set of plans for scarfing with a circular saw.
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarfjig2.htm
Clint
NAILS , SCREWS OR GLUE
- Thread starter catfish
- Start date
If you don't mind, I'd be real interested in seeing some plans for that.
In case anyone is interested, here's a set of plans for scarfing with a circular saw.
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarfjig2.htm
Clint
scarf
I have a router and circular saw jig, but i'd just as soon use a belt sander by hand and eye. I'll see if I can find a drawing and beam it up.Have a nice day,later, Keith
I have a router and circular saw jig, but i'd just as soon use a belt sander by hand and eye. I'll see if I can find a drawing and beam it up.Have a nice day,later, Keith
RE: Clint's citation of "Butt joint with a block
Advantages:
» clean and tight joint line
» very easy to do without any jigs
» OK for no-twist, low-bend or flat panels in structurally non critical areas
Disadvantages:
» the degree of bending "curve of curvature" in tight curves or in twist may be very different than the surrounding plywood resulting in an "unfair" surface with a sharp 'kink' or 'flat' section at the joint.
» strength of joint depends on the cohesion of surface skin within the plywood
» interruption in surface thickness - bad for fiber glassing the affected side
» heavier than other joint types
I use blocks (actually, panels the width of the parent material - 1/4") of 1/8" plywood, 4" wide, and all edges beveled.
Of all types of jloints, I believe the scarfed one is the most elegant. While the reinforcing block is more of a brute-force methodology.
An overriding advantage of the butt block is that if joining panels that have already been cut, your measurements are preserved. Scarfing destroys that - you have to scarf BEFORE you cut. That one fact alone sells me.
Advantages:
» clean and tight joint line
» very easy to do without any jigs
» OK for no-twist, low-bend or flat panels in structurally non critical areas
Disadvantages:
» the degree of bending "curve of curvature" in tight curves or in twist may be very different than the surrounding plywood resulting in an "unfair" surface with a sharp 'kink' or 'flat' section at the joint.
» strength of joint depends on the cohesion of surface skin within the plywood
» interruption in surface thickness - bad for fiber glassing the affected side
» heavier than other joint types
I use blocks (actually, panels the width of the parent material - 1/4") of 1/8" plywood, 4" wide, and all edges beveled.
Of all types of jloints, I believe the scarfed one is the most elegant. While the reinforcing block is more of a brute-force methodology.
An overriding advantage of the butt block is that if joining panels that have already been cut, your measurements are preserved. Scarfing destroys that - you have to scarf BEFORE you cut. That one fact alone sells me.
Heres a link to one way you can make a jig for cutting the scarfs.
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarfjig2.htm
Check out this joint.
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarflock3b.htm
DM
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarfjig2.htm
Check out this joint.
http://www.oneoceankayaks.com/stitchglue/plyshophtm/scarflock3b.htm
DM
Hi DM, I think those puzzle joints are probably the strongest joint of all but even with a dovetail jig and router, can be problematic.
If the panels are all cut to shape prior to doing the puzzle, the set up of the puzzle jig needs to be absolutely accurate. 1mm out on the Jig could correspond to more than 20mm (3/4") out at the end of the panel.
This would necessitate, trashing the lofting sheets for Matts drawings at least, working out the maximum width of ply needed to make each full panel, cut those pieces and then puzzle joint them together. Then mark the full panel on a strip of ply 16 feet or londer.
What might start out as a four sheet boat under normal circumstances could easly turn into a 7 or 8 sheet boat.
I have thought about doing this, and to this end, even bought the dovetailing jig but so far, it just seems like too much trouble and too wastefull of ply.
If the panels are all cut to shape prior to doing the puzzle, the set up of the puzzle jig needs to be absolutely accurate. 1mm out on the Jig could correspond to more than 20mm (3/4") out at the end of the panel.
This would necessitate, trashing the lofting sheets for Matts drawings at least, working out the maximum width of ply needed to make each full panel, cut those pieces and then puzzle joint them together. Then mark the full panel on a strip of ply 16 feet or londer.
What might start out as a four sheet boat under normal circumstances could easly turn into a 7 or 8 sheet boat.
I have thought about doing this, and to this end, even bought the dovetailing jig but so far, it just seems like too much trouble and too wastefull of ply.
The puzzle joint is definately something that has to be planned for by the designer.
When I built a plug mold for a client we tried them out. The biggest benefit was panel identification since it was a multi-paneled hull.
They gave a me a little bit of trouble working with them but not too much more fuss than other methods.
One thing I did not care for was how they looked up close. I feel it didn't compliment the hull. This becomes a more obvious if you use a wood filler that is darker than the wood of your hull. The glue line make the joint stand out more.
Intuitively, they seem like they would be stronger. But is it a solution to something that isn't really a problem?
When I built a plug mold for a client we tried them out. The biggest benefit was panel identification since it was a multi-paneled hull.
They gave a me a little bit of trouble working with them but not too much more fuss than other methods.
One thing I did not care for was how they looked up close. I feel it didn't compliment the hull. This becomes a more obvious if you use a wood filler that is darker than the wood of your hull. The glue line make the joint stand out more.
Intuitively, they seem like they would be stronger. But is it a solution to something that isn't really a problem?
JEM said:
I was wondering about that. I wish he had a couple of up close pictures of the joints on the finished product.
Kayak Jack said:
That's not mine, I just found it while I was searching for kayak kits. In all probability, If I end up making a boat with plans rather than a kit, I'll most likely use a butt block just because of it's simplicity.
In the picture of the finger joints, the pencil is pointing to a complete joint, dont know if it is glued. Doesn't look like that joint is in a peice of okuame, looks like popular to me. Some thing with alot a grain can make the joint REALLY stand out like this:clint said:
There is something about the joint there that draws your attention to it. In my opinion, I think it looks more "out of place" than the straight lines created by a butt or scarf joint. Nature has no straight lines any more than it has uniform curvey ones.
I'll stick with the butt or scarf joints.
DM
Yeah, me too Mouse. I have a reliable, simple, strong solution. IE: my problem is solved. I see other builders struggling to overcome the same problem.
Reminds me of my struggles to replace my cast iron Dutch oven for camp cooking. Answer is: it can't be replaced. It is simple, has no moving parts, and it works. Only disadvantage is heft.
Reminds me of my struggles to replace my cast iron Dutch oven for camp cooking. Answer is: it can't be replaced. It is simple, has no moving parts, and it works. Only disadvantage is heft.
I've been considering some of those shaped finger joints for some furniture projects... but one a boat? :roll:
Clint, I'll try to get the drawings finished by the weekend, if not, this weekend for sure and get them off to you or try to get 'em posted on here, tho' Sparky or Jack will probably need to resize for me as I ain't no computer whiz (tried to email a photo of the grandkids to my ex one time... when she went to print it, it took twelve pages to make the picture... she said it was like putting together a jigsaw puzzle... :roll:
)
Keith, have used the jig for the router with a belt sander on its side. Works great that way, too.
Dad
Clint, I'll try to get the drawings finished by the weekend, if not, this weekend for sure and get them off to you or try to get 'em posted on here, tho' Sparky or Jack will probably need to resize for me as I ain't no computer whiz (tried to email a photo of the grandkids to my ex one time... when she went to print it, it took twelve pages to make the picture... she said it was like putting together a jigsaw puzzle... :roll:
)Keith, have used the jig for the router with a belt sander on its side. Works great that way, too.
Dad
That "puzzle piece" joint looks to me like something that should be done with a 10 ton punch press in one, great big "ker-CHUNK!"
Otherwise, a builder seems to be just asking for trouble and frustration. Those are two of the very things I seek to avoid by building my own boats.
Otherwise, a builder seems to be just asking for trouble and frustration. Those are two of the very things I seek to avoid by building my own boats.
Kayak Jack said:
Jack, dont we all have 10 ton punch presses in our garage. The tool every home boat builder needs. :lol: (Jacks probably already up-graded up to the 20 ton punch press)
DM
Ya caught me, DM! I opted for the streamlined 17 1/2 ton model because I got a date with the secretary if I bought that model.