# Face joining Walnut



## dougn0782 (Feb 13, 2018)

We really want to work with Walnut for new counter tops but the price tag of Walnut is steep. Instead of buying 8/4 walnut planks I am thinking of buying 4/4 planks and joining with a cheaper 4/4 plank on the underside. I understand that the woods may have different movements with moisture. Is there a species that is close enough to make this work?

Flat sawn Walnut has a movement of .0027. Poplar is .0029. Are these close enough to move together without breaking/bowing?

Also what is a good method of joining in addition to glue? Though about drilling holes and using dowels through both boards.

Thanks for the inputs.


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## Loren (May 30, 2008)

I think you'll be alright with that approach
and the poplar. Use a moisture meter though.

Glue alone is fine. You might want to use
screws through the back for clamping pressure. 
You can take them out after the glue is dry
or leave them.


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## Mike_in_STL (Dec 8, 2016)

Is the substrate going to be visible? If not, then I would go with a manufactured product like high density particle board or MDF. Commercial laminate tops are particle board because it doesn't move.


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## AandCstyle (Mar 21, 2012)

Doug, I have never done what you are suggesting, but it looks like the differing movements would be okay. Glue should be all you need to hold everything together.

However, if I were to consider this project for myself, I would think about using walnut veneer over baltic birch plywood and have a piece of 8/4 walnut for the front edge. This assumes that you would never intend to use your counter as a cutting board. FWIW


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## jerryminer (Jun 15, 2014)

> Is the substrate going to be visible? If not, then I would go with a manufactured product like high density particle board or MDF. Commercial laminate tops are particle board because it doesn t move.
> 
> - MikeinSTL


*Don't do this!* Laminate tops covered with *plastic laminate* use pb substrate because it doesn't move much. But walnut *does* move-so gluing it to a non-moving substrate would be a recipe for disaster.


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## Mike_in_STL (Dec 8, 2016)

To each their own, but there is plenty of other evidence and commercially available material on the market that proves this otherwise.


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## jerryminer (Jun 15, 2014)

> To each their own, but there is plenty of other evidence and commercially available material on the market that proves this otherwise.
> 
> - MikeinSTL


Really? 4/4 walnut (or other hardwood) glued to a stable substrate is produced successfully somewhere? Must be a climate-controlled location!


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## jerryminer (Jun 15, 2014)

If you glue solid lumber to a stable substrate, you're inviting the issue that this LJ member had: Cracked Tabletops


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## Mike_in_STL (Dec 8, 2016)

My mistake, speed reading between calls, and misinterpreted the the dimensions. I was thinking much thinner. OOPS, yes, large format would be bad.


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## TheFridge (May 1, 2014)

Had a fella on here recently that did just that and had huge problems.


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## MikeNolan (Feb 4, 2018)

I have glued about 3/16 walnut to poplar and have not had problems. The grains were parallel. I also looked up the expansion rate before I tried it. I would finish all sides to minimize the moisture difference.


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## JBrow (Nov 18, 2015)

dougn0782,

Rather than two layers of ¾" wood face glued to make a 1-1/2" thick countertop, could the countertop be ¾" thick except at the exposed edges and ends? A dual layer of face glued lumber to produce an entire countertop that is 1-1/2" thick would add to the cost and time. Two layers of face-glued walnut only at the exposed edges and ends would leave the impression of a thicker slab, reduce cost, time, and eliminate the concern that prompted your question.

For the optional method, exposed ends would best be glued so that the bottom layer is face joined with the grain running in the same direction as the countertop grain; not across the grain. Cutoffs from the ends of each plank glued to the underside of the plank from which it was cut should result in the best end-grain match.

Similarly, a narrow strip ripped from the plank and then glued to its underside would produce the best match at the exposed long edges. Selecting a profile to rout the edges and ends could help conceal the face to face glue lines.

This optional approach could require shimming the base cabinets with wood (poplar) milled to the same thickness as the bottom layer of walnut.

But if you elect to fully double the thickness of the walnut, poplar would be a good choice. But rather than gluing the bottom layer to the walnut, the bottom layer could be glued-up separately to form the bottom slab. The bottom slab could be screwed (without glue) to the walnut and, for added insurance, short through screw slots cut into the bottom slab perpendicular to the grain of the walnut and bottom slab would allow the two slabs to expand and contract freely and independently. One additional step could be to make the bottom layer perhaps ¼" - ½" narrower than the walnut countertop and centered on the walnut countertop when attached with screws; in case the bottom layer decides to expand more than the walnut.

I am guessing that you are also asking about gluing the walnut countertop together from individual planks and a good method for keeping the boards aligned all along their length. Dowel, biscuit, spline, tongue and groove or lose tenon joints, or closely spaced flattening cauls would all serve to align the faces of adjoining planks during the glue-up. Lumber that is freshly milled flat and to the same thickness would make the edge glue-up and the ensuing flattening less of an effort. When properly applied and fully cured, water resistant wood glue offers plenty of strength without the need for reinforcing the joint.


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