Question about joint strenght for a bed - dominohi

[Jesus Aleman]

Hi, i am looking for some advice from the group.  I a building a bed and have a particular question regarding joining the parts. of the head and footboard. Please see the sketch and photo. Im trying join the rails to the legs using 2 x10mmx50mm dominoes (maybe 3). The rail is made of cherry 4in wide by 1 1/4 thick. My question is whether the glue surface provided in sufficient to withstand all the stress and racking that would be produced on the bed frame, or do i need to look at longer tenon?  Thx in advance.
[attachthumb=3][attachthumb=2]

 

[Ed Bray]

Can I ask some questions?

What size bed? Single, Double, King or Queen?

Who is it for? child, teenager, young married couple, older married couple. some of these will possibly require stronger joints as will the weights of the users.

Are you going to combine the dominos with other joints (dados, rabbets etc).

Answer these and you will start to get an idea of what is required and can probably make a judgement yourself.

 

[Jesus Aleman]

Ed the bed is a double for a kid.  I was not planing on combining the dominos with any other joint or fastener.  Im open to suggestions.

 

[mouppe]

Normally you wouldn't glue the stretchers to the headboard and footboard so you can dismantle the bed to move it if needs be.

I've made a few beds and I have used 10x50mm dominos to align the components and connected the stretchers to the head and footboards with bed bolts.

If you are going to glue it up, no domino will withstand the racking force that could be exerted across a bed frame. The glue may hold but either the dominos, the joints or the stretchers will crack. If somebody moves the footboard six inches to the right, imagine the force that will exert on a 2 inch domino six feet away at the headboard! Something's gotta give way!

You need to add cross-pieces across the bed frame, or screw plywood across the bottom to make it stronger and prevent any racking. Whether you are using a box spring or not can change which method you use.

Here's a picture of one of my bed's internal corners. Either side of the bed bolt is a large domino to help align the joint- mainly when drilling for the bed bolt. The 1/2" or 3/8" plywood sheet (I forget which) is fastened to angle brackets which are screwed to the side of the stretcher. It's not one sheet but three or four pieces with gaps between them to allow some airflow. There should be just an inch or so of clearance on the sides of the box spring with a little bit more at the head and feet to make changing the sheets easier.

The second picture shows the domino mortise holes (narrow setting) in the unfinished headboard.

 

[Sparktrician]

I would not hesitate to use dominoes, as large as possible for the frame thickness, but without glue and only for positioning.  Bed bolts are essential due to the forces Richard mentions.  Little kids being naturally rowdy will load the frame with stress. 

 

[Jesus Aleman]

Gents, thanks for your responses.  For clarity, i am talking about the joints between the rails at the top/bottom of the footboard (or headboard) and the legs. I wasnt planing for this to be a dismantling joint. The long rails that connect the headboard to the footboard and support the matress would be a dismantling joint as you describe.

 

[mouppe]

Oh fine, dominos would be perfect for that. That's exactly how I did mine.

 

[Holmz]

I would not hesitate to use dominoes, as large as possible for the frame thickness, but without glue and only for positioning.  Bed bolts are essential due to the forces Richard mentions.  Little kids being naturally rowdy will load the frame with stress.

Big kids can also load the frame with stress.

 

[Sparktrician]

Thanks for the clarity.  Concur with Richard.  Dominoes and glue work very well for head/footboards.