Properly securing a solid wood table top to a base?

There are two issues that people bring to mind with solid table tops; warping/bowing/cupping, and seasonal movement.

From what I understand, from my research so far, the table top should be allowed movement. My question though is how to properly connect this to allow for the movement but still keep a sturdy surface. The articles I read were complicated.

I'm also wondering how to keep the top flat. My table top will probably be about 3'x4' and about 3/4" thick, with solid oak boards. I know the basics like keeping the boards 4" wide or less, and alternating grain patterns, but I don't know if this alone prevents movement.

Alternating grain might reduce warping, but it doesn't have anything to do with movement.
When wood dries it shrinks perpendicular to the grain. When it gets humid it gets bigger, and so on. Since a table top will have short grain fastened to long grain in the apron, the table will move relative to the apron.
You can't prevent movement, you have to accommodate it by letting it move. You can use special table top fasteners, screw into slots, etc.
If you google you will come up with lots of ideas.

However in a airconditioned/humidified house wood doesn't move much. If you just screw your table top on, the screws will allow the tiny amount the wood wants to move. That said, I still do it right because it isn't that much more trouble.

8 years ago I made a tight fitting drawer front with the grain going the wrong way because it looked much better. I expected I would have to rebuild it because the slightest amount of movement would bind it, but it looked so much better that I wanted to try it. No problems...

Welcome to the wonderful world of woodworking. At the stage you're at, you need lots more info than the couple of questions you're asking in this post. I recommend two books. One is Understanding Wood ,by Bruce Hoadley. It is all about the physics of wood -- how and why it moves, and many other topics. The other is Tage Frid Teaches Woodworking ,by Tage Frid. Frid was a furniture maker, and teacher at Rhode Island School of Design. His book is an introduction to woodworking, with discussions of design, joinery, and many other issues. (The Frid book was originally published as three books. I think it is now only available as one book, containing the first two of the books in the trilogy.)

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Originally Posted by Jamie Buxton

Welcome to the wonderful world of woodworking. At the stage you're at, you need lots more info than the couple of questions you're asking in this post. I recommend two books. One is Understanding Wood ,by Bruce Hoadley. It is all about the physics of wood -- how and why it moves, and many other topics. The other is Tage Frid Teaches Woodworking ,by Tage Frid. Frid was a furniture maker, and teacher at Rhode Island School of Design. His book is an introduction to woodworking, with discussions of design, joinery, and many other issues. (The Frid book was originally published as three books. I think it is now only available as one book, containing the first two of the books in the trilogy.)

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Both look interesting, it would definitely be worth checking them out it seems like. Understanding wood seems like it would help out a lot with general knowledge on wood,a md the tage fridge book looks like it explains everything in the actual woodworking

Just don't glue it... and you'll be fine. Screws still allow tiny movement. I am planning on using pocket hole screws... enough to make a solid connection but not enough to prevent all movement.

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Originally Posted by Tai Fu

Just don't glue it... and you'll be fine. Screws still allow tiny movement. I am planning on using pocket hole screws... enough to make a solid connection but not enough to prevent all movement.

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Better check some wood movement charts. A 3' wide top may move close to .3", depending on the species and how it was cut from the log. Pocket screws will not allow that much movement. You can use them in the middle, but bigger holes will be needed near the ends. I prefer steel offset table top fasteners into slots in the aprons. I use the biscuit joiner to cut those slots.

I think they're called "Z" clips and you can also use figure 8 fasteners. I've have them on a table I built 12 yrs ago and don't have any problems with movement.

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Originally Posted by Troy Turner

I think they're called "Z" clips and you can also use figure 8 fasteners. I've have them on a table I built 12 yrs ago and don't have any problems with movement.

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I second the use of "Z" clips. I've used them several times. I've also made my own - kind of a big wooden L shape. Doing the same thing. The just let the top do what it must. Without breaking or coming away from the frame below.

Rockler sells the Figure 8 fasteners by the bag.

They work.

Here is a relevant link http://www.sawmillcreek.org/showthre...ing-Table-Tops

Also - it is important to start with each board of your top being flat independently of the others even before you bring them together. For this reason I typically start with stock that is thicker than my intended finished dimension. For a 3/4" to 7/8" top I would not start with less than 5/4" stock. I have never paid any attention to alternating the ring orientation of the boards. There are theories to support doing that and others that support simply gluing up with the orientation all the same. My choice is to go for the best looking surfaces and/or the best yield. Flat boards, a flat glue up and proper connection to the base are the essential considerations. For what it's worth, I have never had a table or other solid wood top fail.

Using narrow stock can be useful depending on your shop limitations for flattening stock (hard to flatten 7" boards if all you have is a 6" jointer) but there is no otherwise good reason to use narrow boards other than because you like the look or that's all you have to work with.

You may want to pass on rocklers figure eight fasteners.They stopped making the thick steel ones,And now are flimsy sheet steel the screws just pull thru the holes.The z shaped one are only ones that are any good.But I bet they will be going away soon.As the race to the bottom continues!

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Originally Posted by Jim Matthews

Rockler sells the Figure 8 fasteners by the bag.

They work.

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I too favor the thick steel figure 8 connectors. I take a pass on the stamped ones.

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I like the wooden "buttons". (Odd name for them, though.) You can quickly cut a suitably thick slot with two cuts from a biscuit joiner, or you can do a neater version using a router with an edge guide.

Oak is ok from a hardness perspective (check out the Janka hardness scale). If the wood you are working with is dense enough to be tapped then I would favor that to screws. I did a waterfall bubinga table and my only option was to tap it because it was SO dense that screws would have likely just snapped off in it. If you tap it then make sure you take your time. Chase the first full depth tap with CA glue, let dry, and then tap it again. That should leave you with some nice threads that won't be an issue.

I would suggest going with 5/4 stock at a min for the table top unless you are going for a delicate look. 4/4 can look kind of thin but on a smaller table that might be ok.