Solid Wood Versus Veneer for a Bar Top
Quarter-inch veneer over MDF might show less movement at the miter joints in this large bar top. But can they dance on it in high heels? December 6, 2006
Question
I'm currently in the process of constructing a bar for a commercial establishment. The bar is about 60 lineal feet in length and makes several 90 degree turns. The bar top is 1 1/2" thick white oak and has (7) 90 degree turns to make. Does anyone have ideas on how to join the mitered sections that are too long to go in one piece? The bar is being fabricated and finished in the shop prior to assembly.
Forum Responses
(Cabinetmaking Forum)
From contributor C:
Well, I haven't made them quite that long, but long enough to require joining on site. What we do is, after the tops go through the widebelt, but prior to hand sanding, drill for dowel joints, then hand sand the joint areas while dry doweled together. Then finish individually.
From contributor L:
The tricky part is what happens to the 90 degree miters when all that wood changes moisture content. We did a big solid maple bar last year but strip laminated a round corner to avoid the corner/wood movement problem. That and they really liked the idea (enough to pay for it).
From contributor J:
I would just use dog bones with intermediate splines if I were going to do it. However, I would do it the way contributor L did for the exact same reasons he did, unless there were cabinets or sink cutouts spanning the miters so that they didn't need to be full width.
From contributor D:
Back to the part about the wood's MC changing - even a little bit. A 16" wide bar top in white oak will move 1/4" with a 4% change in MC. Now think about what a board growing 1/4" will do - the effective angle of the miter decreases to less than 45 degrees. Times two for the other piece that is also responding to environmental change. That miter will not stay closed, despite a bunch o' dog bones.
If the wood is forced to stay at 16" by steel or some other unmoving material, then the fibers will compress as it expands, and then when the MC decreases, it will definitely split.
The strategy is to resaw the W oak to about 1/8" or so and lay it onto MDF or a good grade of ply, both sides, same wood, same thickness. Then miter and dog bone all you want. The stable core will hold true, and when the MC changes, the MDF or ply remains stable, and the 1/8" oak is too thin to move. No open miters and no splits.
From the original questioner:
I like your idea. Water resistant MDF would make an excellent substrate. I used dog bones on a solid mahogany bar top 3 years ago and the miters still look great. If the top is sealed on all sides with 2K urethane, will the top still move 1/4" over 18"? I had some concerns about dowels and wood movement as well. A 1/8'" veneered top is not an option, however. The customer specified a solid top. Besides, I don't think 1/8" thick veneer would be enough for this crowd.
From contributor L:
Be sure to cover your behind on this one. When (not if) the miters open, your customer will be unhappy. It won't matter how many coats of urethane you put on it; it will move. They won't remember being told about moisture and wood, but a nice looking contract statement will remind them or the judge.
From contributor T:
I don't tell the bartender how to make drinks - he's a pro. So I tell you how to do the top – contributor D has got the best idea! Listen to a pro.
P.S. Back prime all areas, especially in the ice and glass areas. (LOL)
From contributor D:
That's right - stick to your area of expertise - don't let the customer dictate your methods. Most people have a perception of solid wood as better than veneer, since we have all seen the shoddy "antique" furniture ca 1920's with chipped and peeling QSW oak. Of course, you can do the top so that it will be impossible to tell from solid wood, but you need to be honest with the customer. If 1/8" is too thin (carving initials in the bar?), then it can be beefed up to 1/4". I often do things 1/4, with no problems.
If miters still look good after a few years, it is a testament to HVAC stability - keeping the environment stable enough to prevent wood movement. This is nothing to count on, in my book. One whole house paint job, one good water leak or A/C breakdown, and the miters would open.
The bar top on MDF or ply will not move - you can join and miter how you like. The finish (any finish) would not prevent movement, just slow it down. Don't rely on contract language or HVAC reliability to keep you looking good. Your future rides on exceeding expectations and professional behavior and excellent craft.
From contributor O:
If they really want a solid top... Any chance that the client would accept a change in elevation at each corner - let the top die into a raised corner or span it with a drop? That would obviate the movement problems.
From contributor E:
Expansion across the width of the board as mentioned above, 1/4" over 18", would be the value for flat sawn lumber, but when you lay-up a top of quarter sawn lumber, expansion is across the thickness of the material, and almost nothing across 18". That's why lumber-cored veneer panels are only stable when the core is quarter sawn. This method has worked since glue was invented and will work for you.
From contributor L:
Quartered would be less, but not negligible. How negligible would you like your gaps?
From the original questioner:
Thanks for all of the suggestions. Sounds like most guys are in favor of a veneered top. Although there is a case to be made for solid wood. As I stated earlier, I built a 30' L shaped solid mahogany bar about 3 years ago for an upscale Italian restaurant. The restaurant has since changed owners and is now owned by a Greek family. I received a phone call about 3 months ago from the new owners to come look at some damage to the bar top. Apparently, every Sunday night is Greek night, and a very drunk large woman climbed up on the bar with high heeled shoes and started dancing on the bar top. Before the owners could get her down, a half dozen dime sized dimples over 1/8" deep were now in one of the bar top sections. Fortunately, the finish didn't fail. Had this been a 1/8" veneered top, it would have been ruined. As it turns out, I gave the owner two options, repair it, or live with the bar's new "character." Once he saw the price, he chose the latter.
From contributor D:
You gotta love the Greek ladies that dance on the bar - and in high heels!
I would project that if the bar top was W oak 1/8" thick on MDF, the heel damage would be far less - maybe 1/16". Not only is the W oak much harder, but the MDF is also harder. If you ever do the math to figure out the PSI coming from a 200 pounder in spikes, it is scary. Note that you don't see flooring in mahogany. As responsible woodworkers, we don't want to do anything to prevent dancing on the bar.
