how do you make this 3 way joint strong and durable?

[Albert Lee]

Just wondering if any of you guys have made this corner joint and what would be your ways of making it?

The members are 3 inch square sections.

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I have made it before with domino but I am sure I can make it with traditional mortise and tenon.

[mark mcfarlane]

If this is going into a young boys room I'd consider using lap joints on the horizontal side pieces. They are going to eventually get hung from. After the sides are glued up you could add the top A frame using large dominoes and glue up during installation.

I'd also probably try to connect the 'headboard' vertical pieces to a wall for a little more stability. Boys, and their boy friends, will do what boys do.

[Frederick Skelly]

I have not. But it looks like it might be candidate for some Japanese joinery. It's 3" square so that opens up options. Maybe a combination of a lap joint and M&T?

[Doug Garson]

I think you should also run pieces across the top at the head and foot ends and just to complicate things you should also consider how to disassemble the bed for moving.

[Albert Lee]

If this is going into a young boys room I'd consider using lap joints on the horizontal side pieces. They are going to eventually get hung from. After the sides are glued up you could add the top A frame using large dominoes and glue up during installation.

I'd also probably try to connect the 'headboard' vertical pieces to a wall for a little more stability. Boys, and their boy friends, will do what boys do.

Thanks Mark, I have come up with this below, a good compromise between manufacturing speed and durability? some modification maybe needed... this is just a quick sketch

joint.jpg

[Michael Todrin]

I like where you are going with that Albert. Here is another option. Keep the tenon on the vertical member. Run it through the horizontal and up into the rafter. Draw-bore through the rafter to keep it all in place.
CD2C5C68-B807-4B9A-80A6-49191D3E7186.jpg

[mark mcfarlane]

I like where you are going with that Albert. Here is another option. Keep the tenon on the vertical member. Run it through the horizontal and up into the rafter. Draw-bore through the rafter to keep it all in place.
CD2C5C68-B807-4B9A-80A6-49191D3E7186.jpg

That looks very good.

[David Stone (CT)]

Your drawing looks like a good approach, except that, unless this is going to be glued up in place and never removed from the room it's in, it would seem like some part of the joinery needs to be knock down fasteners, no? Usually on beds the headboard and footboard are permanently joined and the rails are the movable parts. Given that the parts are 3 inches square, there's room to introduce a 1/4-20 threaded insert into the end grain of the tenon you show on the horizontal member tenon and have that receive a connector bolt that passes through the vertical member and holds the thing together.

[Michael Schuch]

I can see why you wouldn't want to glue a joint like Albert's due to wanting to disassemble it and move it at some later date. My first thought was to drill holes through the tenons and peg the joint together. You could even dove tail the tenons and peg them together.

It took me forever to figure out where Michael was trying to go until I figured out the picture was rotated 90 degrees. That makes sense except the joint area on the #3 piece will be wider than the width of the #1 and #2 pieces. You could put a birds mouth on the #3 piece in the same configuration which would also add a bit of strength.

Mark makes a very good point about boys hanging from it which would almost make me want to weld up a bracket to hold the 3 pieces together.

[Derek Cohen]

Albert, this is an option that is geared towards assembly on-site and disassembly in the future.

The post is rebated for the side horizontal sections to fit with half-lap joints. These two sections are simply attached with a bolt through the centre of the half-lap. They are supported by the rebate alongside, so should remain firm. This should be strong joinery from which to hang a curtain, etc.

Plan view (from the top looking down) ...



Hope this is clear.

Regards from Perth

Derek

[Albert Lee]

just an update,

Thought I make a sample anyway, it will be assembled/disassembled so glue up is not feasible.


joint4.jpgjoint2.jpgjoint1.jpgmove3.jpgmove1.jpg

lesson learnt:
1. Always buy the biggest tenon plate if you can - its always the angled tenon that gets you.
2. I need a bigger workshop - I had to pull my moulder out to do this 45 deg cut.

[Jim Becker]

If you carefully plan those laps and intersections, you can likely incorporate a bolt through all of them to keep them secure without glue. The bold head can be countersunk and a contrasting or matching friction fit cover can conceal the fastener. Figure out the intersections.