wood counter top with herringbone corner?

[mound]

a friend of mine has a bunch of 10/4 walnut he cut up and has been drying for a few years, and he wants to make a kitchen counter top out of it. (pretty basic, L shaped counter about 7' on the long side and 4' on the short side)...  He plans to re-saw it (hoping to yield roughly 3/4" stock) and glue up 4" wide flatsawn boards to get the final ~24" depth. 

Normally I'd tell him to glue up two panels over-length and then put a miter on each to make the corner of the "L", but he wants to do a herringbone pattern. 

He plans to glue-up and assemble the entire "L" in the shop and carry it into the kitchen for install. 

What's the glue-up process then? Seems on first thought that the 24" wide panels need to be glued up/assembled into the herringbone pattern all at once? Or would you cut that staircase pattern into each panel after glueup? Just trying to think through the logistics....

[Willyou]

IMHO, I think cutting the two sides of the herringbone pattern accurate enough to get a good fit is not impossible, but difficult. I believe the best way is to use some slow setting glue and make the herringbone during the glue-up. I would start with the 7' panel making sure that each piece is squarely cut and marked so that when edge glued, the stair steps at the corner are accurately spaced. Once dry, glue up the 4' section including the joints with the 7' section at the stair step corner. I would use biscuits in the end grain to help keep them aligned.

[FS7]

Is the suggestion that the miter joint will itself have a herringbone pattern? It's not technically impossible, but I'll go ahead and see that's pretty much not going to work. That will be insanely difficult.

Having accurate miter cuts on two pieces and using miter draw bolts will work (that's how it is done for laminate countertops) but having a 45 degree joint consist of "teeth" is just frustration waiting to happen.

[mound]

@WillYou - thanks, yah I think that makes sense. Slow set, biscuits/dominos, well align everything the clamp.

@FS7 - no, there would be no miters involved. Simply that the two legs of the "L"come together as a herringbone pattern (each end gets that staircase pattern)

[DaveR1]

there would be no miters involved. 

[mound]

Thanks Dave you beat me to it with the sketchup drawing! Yes that is the pattern I'm referring to.

[AHill]

You don't really need to cut any parts.  Let the pattern interlace like below.  Glue-up should use biscuits or loose tenons.

[Cooler]

From a logistical point of view, this would be a difficult counter to transport. 

While it would make an interesting joint for woodworkers, I suspect a mitered corner would be preferred by most housewives.  You will have to survey the intended recipient. 

If you are going to miter it, I would recommend using two dowels in the joint to assure alignment.  I used this joint fastener from Rocker plus a couple of non-glued biscuits.  I think if I had wet the biscuits it would have aligned better.  The tops are out of plane by enough that you can feel it, but it is not apparent visually.  I think dowels would have resolved that issue. 

I've seen pocket holes used too.  But you would either have to get under it to set the screws or flip the counter over after screwing and I am not certain that a pocket hole screw will handle that stress.

[jteneyck]

Mitered corners in wide solid wood will open up as the RH changes with the seasons.  Guaranteed.  It works with laminate countertops  because particle board has almost no seasonal expansion.  

The herringbone pattern would work a lot better but will be a bear to cut.  The easiest and most bullet proof construction with solid wood would be a butt joint, fitted together with a spline glued only to the long grain section, and held together with the zipbolts Cooler showed.  That will allow for seasonal expansion without self destructing.  You can pin the spline to the other half with a single dowel to force the expansion/contraction where you want it.  Pin it near the front and all the movement in the cross grain section will go towards the back wall, or pin it in the middle and the movement will be equal towards the front and back, etc.  

John

[Cooler]

Mitered corners in wide solid wood will open up as the RH changes with the seasons.  Guaranteed.  It works with laminate countertops  because particle board has almost no seasonal expansion.  

The herringbone pattern would work a lot better but will be a bear to cut.  The easiest and most bullet proof construction with solid wood would be a butt joint, fitted together with a spline glued only to the long grain section, and held together with the zipbolts Cooler showed.  That will allow for seasonal expansion without self destructing.  You can pin the spline to the other half with a single dowel to force the expansion/contraction where you want it.  Pin it near the front and all the movement in the cross grain section will go towards the back wall, or pin it in the middle and the movement will be equal towards the front and back, etc.  

John

I should note that the counter top will be fully supported and other than keeping the joint together almost no stress will be put on the joint.  It will be supported almost its full length (with an overhang if seating is used).  It will either be held to the cabinets with clips or more typically construction adhesive and the cabinets will be anchored to the wall so lateral motion will be absent.

All of which is to say that the joint will not be greatly stressed at any time in its life except for during the installation process.