Need advise sizing M&T joints for a bed

[shoottmx]

Building a king size bed following this design except that the footboard rail will be straight across where the black line is drawn:

[attachment=21745]

Going to use these to connect the side rails to the head & foot board:

[attachment=21746]

Following the dimensions on Vermont Shaker's web site, all 4 rails are 1 1/4"x 6" cherry. The legs are  1 3/4 x 1 3/4" cherry. Their info says the rails are tenoned into the legs but no size is given. What tenon size should I use on the head & foot rails? I  was thinking 3/4x 1-1/4 x 5 1/2". That leaves 1/2" of material on each side of the leg and 1/2" at the end of the tenon. Would a narrower tenon be better? Or thinner? Should I use West epoxy for maximum strength? Or TBlll? 

The screws for the side rail connectors will have to go thru the tenon. Planning to use #10 x 1-1/2". Does that sound ok? 

Advise appreciated!

g

[Willyou]

Your concern would be the width of the cheek side of the mortise. Your proposed dimensions will leave 1/2" here and I think that is good. My gut wonders if it would be better to make two 2 1/2" M&Ts with 1/2" in between. This would leave 1/4" shoulder at the tenon ends which is more than enough. I think that this would maintain some strength in the mortise walls that might be lost by a 5 1/2" long one.

[Admiral]

Your concern would be the width of the cheek side of the mortise. Your proposed dimensions will leave 1/2" here and I think that is good. My gut wonders if it would be better to make two 2 1/2" M&Ts with 1/2" in between. This would leave 1/4" shoulder at the tenon ends which is more than enough. I think that this would maintain some strength in the mortise walls that might be lost by a 5 1/2" long one.

Agree with the double tenon/mortise; that adds significant strength (as I assume the bed will get some lateral stresses on a regular basis...
 ) . 

[shoottmx]

Thanks Willyou. Appreciate you pointing out the error on the mortise cheek dimension, I'll edit my post. I like the thought of two 2 1/2" tenons. Thank you for your advise.

g

[Willyou]

Thanks Willyou. Appreciate you pointing out the error on the mortise cheek dimension, I'll edit my post. I like the thought of two 2 1/2" tenons. Thank you for your advise.

g

I think what you said was correct. I was just repeating it.

[shoottmx]

I think what you said was correct. I was just repeating it.

My original post had "That leaves 1/4" of material on each side of the leg ". I edited the text after your post.

Thanks again,
g

[mike4244]

Building a king size bed following this design except that the footboard rail will be straight across where the black line is drawn:



Going to use these to connect the side rails to the head & foot board:



Following the dimensions on Vermont Shaker's web site, all 4 rails are 1 1/4"x 6" cherry. The legs are  1 3/4 x 1 3/4" cherry. Their info says the rails are tenoned into the legs but no size is given. What tenon size should I use on the head & foot rails? I  was thinking 3/4x 1-1/4 x 5 1/2". That leaves 1/2" of material on each side of the leg and 1/2" at the end of the tenon. Would a narrower tenon be better? Or thinner? Should I use West epoxy for maximum strength? Or TBlll? 

The screws for the side rail connectors will have to go thru the tenon. Planning to use #10 x 1-1/2". Does that sound ok? 

Advise appreciated!

I also like the double tenon. As far as glue, you can use yellow glue, or no glue if you want. I prefer draw pin construction as this does not need glue or clamps. Done correctly draw pins will pull the joint tight and stays there. I generally leave the pins 1/8" proud and round the edges slightly with sandpaper on a narrow stick.
Draw pin are generally 3/8" dowels. You bore thru the leg with a 3/8" brad point drill. Back up the hole or only bore til the point comes thru and finish boring from the other side. Now insert the rail into the leg as tight as it will go. Mark the center with a transfer punch or the point of the bit used to bore the hole. Remove the rail. bore the 3/8" hole 1/16" towards the rail shoulder, NEVER away from the shoulder. Insert rail, cut a 3" length of dowel. I put a slight bevel on one end with a pencil sharpener. Bevel the end slightly with any means you like, sanding, pencil sharpener etc. Insert the point into the hole in the leg and tap the dowel thru til the point comes thru the back of the leg. This will pull the joint tight. Repeat for other pins. I use a fine tooth Japanese pull saw and a scrap 1/8" thick to cut the draw pins proud of the leg. 
Then round the edges with a sanding stick . I generally PSA paper on a small stick. If you like there are other ways to deal with the draw pin.
Cut them flush ,sand a bit to remove scratches from saw teeth. You can buy round head plugs and the draw pin is driven deeper to account for the plugs tenon. I know that some people use glue and draw pins, not necessary to use glue. 

mike

[shoottmx]

Agree with the double tenon/mortise; that adds significant strength (as I assume the bed will get some lateral stresses on a regular basis...
 ) . 

 

 
 
 


g

[shoottmx]

Mike,
Thank you for the detailed explanation. Amazing to me that by draw pinning the joint it can be done without glue. Do you use a dowel made of any wood or something specific? Oak maybe? I'm inclined to give pinning a try but with glue. I think the round plugs would be my choice.

Thank you again for your information,

g

[mike4244]

Mike,
Thank you for the detailed explanation. Amazing to me that by draw pinning the joint it can be done without glue. Do you use a dowel made of any wood or something specific? Oak maybe? I'm inclined to give pinning a try but with glue. I think the round plugs would be my choice.

Thank you again for your information,

g

I generally use the same wood as the rails. Sometimes a completely different dowel is used for contrast. It does not make a difference which wood the dowel is made from. English bodgers ( chair maker) often carved a pin fairly round . 
mike