Sliding Dovetail Joints

[CARS]

In my build journal, I toyed with the idea of attaching the spars to the side ply with dovetail joints to eliminate any fasteners.

Here is a test that I did:



I just took a scrap 1"x6" and cut the grove and attached 2- 1"x2" scraps to them to simulate the spars.

(I need to spend more time fine-tuning the router depth for a tighter fit, but you get the general idea)

Anyone done this??

Is it worth the additional work??? Once I get the router set up and make a guide/jig to make repetitive groves in the sides I think the job will just fly along. But is it going to be any stronger than just using screws and glue??

I never cared for screwing into end grain. That is why this came to mind.

[TBuilder]

Anyone done this??

How about dovetail + fasteners!

http://tnttt.com/viewto ... 4&start=30

You need to scroll down.

[CARS]

Yeah!! That is the type of jig I was thinking of. Thanks for posting the link. I might have to practice a few dozen times to get the tolerances right, but it should be a great, strong joint.

[kevingb]

It wasnt that hard once you get over the puzzle. I did it so i can easily tear down incase i need to do work on sides or etc. Once I'm ready to fasten the sides... they will be glue and screwed.

1/2" 14degee dovetail bit and 5/8" collet
Depth of cut 3/8 (MDO is true 3/4")

1/16" from large diameter of bit to side of collet

Once you set depth of routerbit... do not change until your completly finished.

Tail's (side of teardrop) -
http://www.tnttt.com/gallery/image.php?image_id=77447

using 1-1/2 width just add 1/8" (1/16" x 2 to use maximum width)
1-5/8 width of jig, then work with the length

Pin's (Rib) -
http://www.tnttt.com/gallery/image.php?image_id=77449

This is the tricky one...
Cut on groove at 5/8" for collet, then spaced out another 5/8" groove 1-3/8" offset. Subtracting the (1/16" x 2 from above). This dimension will be dependant on the depth of router bit.

During setup i used a flat scrap piece, instead of testing on end piece. once you have it right then you can attach the 90 degree piece to the jig.

If you look at the right groove at the bottom, you will see where i did multiple cuts on table saw. My final spacing ended up at 1-5/32". Alway better to start large on this piece.

I only cut 2 sides of the pin, the Tail had 3 sides. this way when i get ready to glue and screw. the bottom of the Tail will capture most of the glue drips.

Good luck.

[Lgboro]

So far I have used dowel pins and biscuit joints in combination on the floor. roof and walls to the point they are completed. The wood will shatter long before the joint will give way. Trim, doors and windows are the only place I intend to use mechanical fasteners. If anything, so far my shell is overbuilt - far sturdier than commercial units I have helped work on. And I have used only cedar wood for my build to help keep the weight on the lower side for all the toys I am including in my build. I'm sure a dovetail joint should give you plenty of strength for your tear.