White ash bench seat design and construction

[Robert Trotter]

I am going to make a bench seat for the entrance for our home. It will be more to place things on as you come home and leave than to sit on, but will be used in that situation as well. Here are some pics of the design concept.

white ash bench.jpgwhite ash bench top.jpgwhite ash bench low angle.jpgwhite ash bench section view.jpg

The bench will be made from white ash. For the seat I have 6/4 and for the legs I have some 8/4 lumber.

The design:

• About 1200mm long and 340mm seat width. Height about 460mm.
• Wanted a sort of seat floating above the legs feel, so the stretchers are inset and run under seat members.
• I have two stretchers - I figured it would be better for torsional strength than a single stretcher in the middle.

Questions:

1. What do you think of the overall design and concept?
2. For the stretchers - what would be the minimum size I can get away with?
3. Main Stretcher - From 8/4 stock I figured I could get maybe 40 to 45mm square. Would this be too small?
4. Or should I Look at at using 6/4 and maybe using 30x60mm?
5. For the top stretcher (?) of the end leg frame, can I use the same square stock as the legs of about 40-45mm or do I need to go to say 30x60mm?

Joinery:

• Mortice and tennon for the leg frames and the stretcher to leg frame joints

Seat Connection:

How to connect the seat and the seat supports and the supports to the base?
The seat supports are shown as about 30x30 for a 30mm gap between the seat and the frame. Could be more?
or Should I look at something like 30 wide x 60 high with bridle joints
or Should I look at wider, flatter supports like 60mm wide and 30-35mm thick just fixed by screws?

1. screw the seat boards to the supports only?
2. use bridle joints on the supports to set the seat boards into and then screw?
3. For the supports to the frame-

• just screw them on
• or bridle joints of say 10 or 15mm and screw or glue?
• If bridle joint what depth is needed?

Any comment on design and construction?

Thanks,
Rob

[Todd Burch]

Hi Robert. Visually, it seems that if I set my heavy hiney on the end of the bench, it would tip over.

[Robert Trotter]

End-for-end? I don't think so as the leg is only about 60mm from the end. While the support are inside, the forces would transfer to the legs which would be under you B*m. But there would be bending forces in the top boards but I was hoping the 30mm thick boards (or what ever from 6/4 planks) would take that. That was the way I was looking at it.

Rob

[Mike Svoma]

I like the design, with one issue. It looks like there would be a possibility of racking from side to side.

[Robert Trotter]

Yeah Mike, that was one of my concerns. I was wondering do I need to use 30x60mm stretchers M&T into 60mm piece in the end leg frames? Or would I need to go even more?
Rob


Also - any comments about the best joinery and connection methods?