Board of woodworking joints

[Cody Cantrell]

I am a High School shop teacher and would like to build a board of all of the significant joints that my students would encounter and/or use. When I was in high school myself I remember having a 4x4 piece of plywood on the wall that was painted a light green color and had joints both assembled and disassembled. At the time I didnt give it much thought but the teacher probably didnt know much about it himself. I have not been able to find anything by doing a google search. I would like to make a similar board for my room and was wondering what joints everyone thought would be pertinent for high school shop students to know. Thanks for any input, I will try and post a pic when I get it completed. Thanks for the suggestions.

Cody

[Frederick Skelly]

Great idea Cody. Heres my basic list. Obviously there are variants (e.g., through joints vs stopped joints) of several that I wont list. Heres the ones that came to my mind: butt, dado, rabbett, miter, dovetail, box, finger. Im forgetting some, but its a start.

Another idea. Arrange them on the board from weakest joints (butt) to strongest joints. Or from easiest to make to hardest to make. Etc.

Good luck. I envy you man - wish I could be a shop teacher. Id really enjoy that!

Fred

[Sean Hughto]

The first thing they need to understand is grain and the difference between long and end grain and its inplications for wood movement and gluing joints. So I might use the old bundle of drinking straws as a way to think about it. "If you glue the straws together along their length, the bond can be as strong as the wood. If you glue them end to end, the glue just goes into the straw and forms a very weak bond."

Whole there are tons of joints you might show them, there are really only a few that are really the go to ones woodworkers use all the time. The edge joint for gluing up panels a tops - wide elements in a project. The mortise and tenon. The dovetail. I might add spline, rabbet, tongue and groove, lap, dowel, biscuit. You might show fasteners like screws and cut nails too.

just some ideas.

[Brian Holcombe]

http://www.gutenberg.org/files/21531/21531-h/21531-h.htm

all joints are easy to make, some just take more steps.

[Tom M King]

I can probably send you some. I have a bunch of pieces for window sash, probably test run pieces for various dovetails, various mortise and tenon joints, and probably other stuff, if the help hasn't taken them home and burned them for kindling.

[Daniel Rode]

Here's the list I'd use:



Butt
Miter
Lap
Bridle
Mortise & Tenon
Dado (housing)
Dovetail
Box
Cope & stick


The butt joint might be shown with dowels, pocket screws, etc. as it's typically reinforced somhow.

Like Sean wrote, understanding wood movement and grain direction is critical.

[Daniel Rode]

The more I think about it, the more I want to make a display board of woodworking joints. I'm just not sure what I'd do with it.

I'd give it to the local school for shop class, but they no longer offer shop.

[Cody Cantrell]

Thanks for the ideas guys. Here is the list of the joints we use most.
Through dovetail, hand cut
Half Blind, off the Omni Jig
Mortise and Tenon
Edge to Edge, sometimes with biscuits on large panels
Half Lap
Miter
Butt joint, typically with Pocket holes or screwed/nailed through.
I like the idea of using different fasteners.
Wasnt sure how in depth to go though. Mortise and Tenon can also be through, Internally wedged (cant remember what this is called), externally wedged, tusked, etc. Where do you draw the line? Keep the ideas coming I like it.

Cody

[Brian Holcombe]

My personal list would be mortise and tenon, all manner of dovetails, rabbet, bridle, half lap, Edge-to-edge for glue ups. If you master those you can build a great deal of things well.

I'd skip the pocket screws and butt joints because I would not was to encourage their use (or misuse) in favor of a scarf joint if it's an advanced class.

[Daniel Rode]

IMO, you can't ignore the butt joint. It's the simplest joint and depending on grain direction, can be very strong very weak. An end-grain to face-grain glue connection is weak and therefore requires reinforcement. That core lesson in how grain direction affects joint strength is important.

A housing joint is essentially a variation of the butt joint. It adds some mechanical support from the sides as well as some long-grain to long-grain glue surface. A sliding dovetail is a further improvement.

This is after all, a shop class teaching kids the basics.

[Jim Koepke]

Mortise and Tenon can also be through, Internally wedged (cant remember what this is called)

Is that possibly a fox wedged tenon?

It might be fun to show a butt joint with one next to it broke open labeled, "typical butt joint after first use."

This reminds me of the knot boards some seafarers used to make while at sea.

A recent episode of the Woodwright's shop had diagonal dovetails. These are used on the corners of skirting around the bottom of a chest.

http://video.pbs.org/video/2365309216/

Another interesting thing with dovetails is the pins and tails can be shaped. Here are a couple of threads on 'lovetails':

http://www.sawmillcreek.org/showthread.php?102048-Cradle-with-quot-Lovetails-quot
http://www.sawmillcreek.org/showthread.php?95360-Lovetail-Experiment-amp-Practice

If you discuss joinery, don't forget to mention the handle in a hammer is held in place with a wedged tenon.

On occasion I have found a lapped dovetail joint to be useful.

When you have your "Board of Woodworking Joints" set up it may be good to have a printed handout with explanations of how, where, when and why each joint comes into use. Either that or have the students take notes during the discussion with word of a test on the subject.

Don't forget the draw bore tenon.

I also like tongue & groove and shiplap joints. Though often they are not glued and are used to allow for seasonal movement.

Sounds like fun.

[Rich Harkrader]

You might have a look at Ron Herman's Joinery Challenge for ideas. It's an excellent instructional DVD.

http://www.shopwoodworking.com/the-joinery-challenge-w5168