Wood kitchen countertop with 90 degree

[andrew whicker]

Hi,

I'm going to be building a countertop out of 8/4 or 6/4 walnut with a L and an under mount sink. (6 ft x 9 ft, measured on the wall)

I'd like to have a completed template built on site and build the L at my shop. I'd like to use a miter, cut with my tracksaw. My thoughts, based on talking to others / looking around online is to glue the miter joint with epoxy and dominoes. Let the two sides of the L float with hardware. Clamp the miter cut with countertop clamps. Leave a small gap between drywall and countertop.

I'm still trying to figure out finish.

What should I be thinking / where should I look to make sure I understand all the variables? Recommended videos or books? Is there something I'm not thinking of?

[Kevin Jenness]

Determine how much the miter angle will change throughout the year based on species, grain orientation and seasonal humidity variations. Then decide if that much movement is acceptable given the design. Is there a backsplash to disguise the movement at the walls? Do you need to fix the leg with the sink in it?

Your plan will work if the L is allowed to float. You may need to tune up the joints with a hand plane or router and straightedge. Be sure to do a dry fit. Zip bolts are quite handy for pulling the joint together, or you can screw some clamping ears to the outside of the L and use bar clamps.

The look is different, but you can make an L that maintains its angle using a butt joint glued at one point and allowed to float with a spline or loose dominos.

[Doug Garson]

Check out this video.
https://www.youtube.com/watch?v=4-OGtAs12ZQ

[Dave VanDewerker]

I just put in a wood counter top in my kitchen last year. I made my counter with edge glued maple, 7/8 x 1-1/2, so wood movement is much less of an issue. The finished counter is a bit under 1-1/2 inched after I finished planed and sanded. I finished the counter with Pure Tung Oil, I did not want a film finish that would would crack or dent, Tung oil can also be reapplied when ever needed with a simple light sand and reapply.
I would be more concerned with the under mount sink that will expose end grain to water. My sink is a top mount and I flooded the end grain with tung oil after I cut the hole for the sink and I used a very heavy bead of silicone caulk under the sink.
So far the counter still bead water and everything wipes off without leaving any stains.

[Frank Pratt]

I've done 2 wood (actually, 1 wood, 1 bamboo) counter tops with 90* miter joints. No issues with movement because the short side of the 'L' was secured with movement allowed for. They were glued with epoxy, double rows of biscuits & counter top bolts to pull it all together.

Both counters also have undermount sinks. the counter underside & the edge of the sink cutout were saturated with slow setting epoxy & a heat gun. The sink was then secured with screws & epoxy. Not staining, checking or other issues. Of course, even with all precautions, proper care in daily use is still essential.

[andrew whicker]

Thanks for the replies. I'm going to talk w/ the contractor to see who installs the sink. I don't mind who does it, but I'm not sure it's me. Plus the sink will have to be supported.

[Rich Engelhardt]

I'm still trying to figure out finish.Waterlox (https://www.waterlox.com/Waterlox-for-Countertops)is about the only manufacturer that comes right out and says, "Use our product" on kitchen and bath counters. That's a pretty ,,,bold,,,statement.

[Mark e Kessler]

Waterlox (https://www.waterlox.com/Waterlox-for-Countertops)is about the only manufacturer that comes right out and says, "Use our product" on kitchen and bath counters. That's a pretty ,,,bold,,,statement.


I can confirm that Waterlox is excellent finish on Cherry Butcher block, have had it on mine for I think 4+ years now no issues.... I can also confirm my L counter has moved more than I would like...LOL

edit, its been since 2013 that I did the finish, now I am impressed with how durable Waterlox is… It was made from salvaged Cherry flooring from the house and only meant to be temporary…. here is a pic of when I installed it…

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[andrew whicker]

I can confirm that Waterlox is excellent finish on Cherry Butcher block, have had it on mine for I think 4+ years now no issues.... I can also confirm my L counter has moved more than I would like...LOL

edit, its been since 2013 that I did the finish, now I am impressed with how durable Waterlox is… It was made from salvaged Cherry flooring from the house and only meant to be temporary…. here is a pic of when I installed it…



Nice job! In what ways has it moved? Are your joints still tight? That's tough having two big joints like that.

[Adam Herman]

waterlox is excellent on a beech desk that my wife and I use for working from home, and an island of reclaimed bowling ally, long leaf pine/maple/walnut. I have been very impressed with how it looks after a few years of use.

[Jim Dwight]

Pocket hole screws would be another way to "clamp" the miter while the glue sets.

[andrew whicker]

yeah, that guy in the video is right... end grain screws don't work super well.

Also, I'm giving the option of a butt joint. I'm assuming they will go with a miter (I think it's more or less objectively better looking) so I may indeed have side grain to clamp to.

[Mark Bolton]

I can confirm that Waterlox is excellent finish on Cherry Butcher block, have had it on mine for I think 4+ years now no issues.... I can also confirm my L counter has moved more than I would like...LOL

edit, its been since 2013 that I did the finish, now I am impressed with how durable Waterlox is… It was made from salvaged Cherry flooring from the house and only meant to be temporary…. here is a pic of when I installed it…



That top eliminates a lot of the catastrophic movement issues of a 45 degree miter with the 45 degree sink section with the square connections to the pie cut corner. The true 45 degree miter if the legs are long can result in a mile of movement.

[Mark e Kessler]

Nice job! In what ways has it moved? Are your joints still tight? That's tough having two big joints like that.

Thanks, moved about 1/8” on the left joint and 1/16” on the right BUT I did not glue, only used silicone in the joint because I had planned on these only being there a year or so then replace with Soapstone. I also just used lamellos, I suspect if i used a domino and glue/epoxy with zero slop for the first one it may reduce or eliminate the offset in the front as long as you left a gap in the back between the wall and the counter. Also I used dog bones to pull it together, don’t pocket screw it…

[andrew whicker]

They want the butt joint. I didn't expect that. So either I use pure mechanical (dog bone connectors) or I use the tenon / breadboard method.

[Kevin Jenness]

Zip bolts plus a spline will keep the joint together and flush. Glue the spline where you want it fixed and let the rest float.

[andrew whicker]

Hi,

With wood, I'm assuming I'll want a negative reveal around the sink to keep as much water off of the end grain as possible. What are your thoughts / experience?

cheers,

[Dave Sabo]

Hi,

With wood, I'm assuming I'll want a negative reveal around the sink to keep as much water off of the end grain as possible. What are your thoughts / experience?

cheers,


You definitely need the mechanical connectors for any joint. I also prefer a butt joint, but that's neither here nor there.

I would seriously consider designing the sink opening without endgrain. My last top was made with a thin sliver of face grain laminated onto the endgrain. The sink was cube , so it was easy. Not so much with a D shape, oval or round type. Baring that , I'd use penetrating epoxy sealer on the endgrain . CPES is a brand, but Minwax makes one too.

You should finish the underside of the counters with the same finish as the top side.

Waterlox is pretty good and what I used 20+ years ago. It's a PIA compared to newer finishes that also require less maintenance and have much faster dry & cure times. OSMO PolyX is a much better choice, and Rubio Monocoat is even better than that. Though, more costly.

If you have a deep enough reveal , a kerf on the underside to provide a drip break is a good idea. Be sure it doesn't get filled with silicone when mounting the sink !

[Richard Coers]

You are incredibly fortunate they chose the butt joint. If you had gone with the miter, and screwed it down to the cabinets, the miter would have opened up every seasonal change. If you use flat sawn lumber, the width of the top will change about 1/4" and that will certainly open a miter joint. Be sure to allow the top to still float around on the cabinets.