Expert: Jamie Yocono - 1/16/2007

Question
Hello again Jamie and thanks for the quick reply.Ok here is the deal with the inlay on the top.First I will surface 1 face and edge and glue upe a 4x4 blank.Then take this top to a cnc router to surface and cut the top.Then set the machine up for the wedge groove(5 degrees) 2 inches in from the sides.After this swith boards.On the inlay board, be sure to reference off of the same surface as the groove was cut,matching bottom I.D. with top O.D.The inlay stock is thicker by a quater than it's inset so it can be surfaced off after insertion.This is my idea.I am interested in your view.Thanks'Will.
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Hello again Jamie and thanks for the quick response.I think I am going to go with 8" after all thought.I can't go below this for the customer wants the base as inconspicuous as possible.She also despises the "country" look so I must keep the base tucked as much as possible.I will definately experiment with this before actually committing.This table will have a circuler inlay 2" in from the side.It will be wedge shaped and only 5/8" deep into the top.What are your thoughts on this?Thanks,Will.
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Thanks for writing back so soon Jamie.When I first wrote you the question I was more concerned with the top not having enough apron suppuort under the edge grain side however you raise a very valid point.The wood I am using is very heavy,Jatoba,and the legs are 2 3/4" solid stock.What do you think of nine inches on the cant?
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Hello Jamie.First I would like to compliment you on your clear and precise replies.I am building a  4'0"X4'0" round Jatoba table for a client.I plan to cantilever the top 12" around a leg and apron base fastened with figure eights to the apron.The glue up will consist of 4 3/4" widths,1 1/4" thick.Is the 12" cantilever too much?
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Hi Will,

Thanks for your nice words about my answers on this site. I sure hope they help the people who write to me! Sometimes, it's hard to tell.

Anyway, let me get this straight- you're making a round table top (4' diameter) and putting it on a square base? And then- you're using figure-8 table top fasteners to attach the top, right? And your question is regarding the 12" overhang that you want to use, am I correct?

To be honest, I think a 12" overhang is too much on a 4' table. Look at it this way- if your top is 48" and you have a 12" overhang all the way around, your base is 2' by 2'. I think it's not enough of a footprint to keep your table from tipping. Think of how people get up from a table- they slide their chairs back, and push off of the front edge of the table. If someone big does that, it's quite possible that the table could tip.

Now, don't get me wrong, I recently built 2 large tables that incorporated a 12" overhang. It can be done. But the tables were big - one was 6' square and the other was 4'x 6'.  They both had a large footprint, and VERY heavy legs. The legs were 5" x 5" solid wood. So a large person pushing off of one of those tables wouldn't be able to tip it, since the tables were quite weighted. The large overhang was counterbalanced by the large table/base configuration.

But on a table the size that you're working with, I don't think it's going to be stable enough.

I've thought about this for a while, and the only solution I can come up with is to make the base bigger, say with a 6" overhang all the way around. This would kick the legs out closer to the edges, and make it less likely to tip. I was going to suggest a center pedestal, but I've always thought those are rather easy to tip, too. So I think the only solution is to broaden the base.

I hope this helps, let me know what you think. If you come up with a different solution I'd be glad to answer any questions you might have. Good luck, you've putting a lot of thought into this design, and I'm sure you'll come up with a proper solution.

Jamie Yocono
Wood It Is! Custom Cabinetry
Las Vegas, NV
www.wooditis.com

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Will,

I really feel that the design question here isn't about the edge grain having enough support, but rather, about the small footprint of the base and it's proclivity toward tipping.

If your top is properly made, that it- with the seasonal rings facing alternate directions when the planks are positioned, it shouldn't bow or cup at all. Furthermore, most woodworkers agree that a glue seam is actually stronger than the wood itself, so if you tried to break apart that top, it wouldn't break on the glue lines, but rather- somewhere within one of the boards. That said- it shouldn't make any difference what part of the top is cantilevered over the edge- whether it's the end grain or the side edge of the top.

Once again, I go back to the tipping factor. I am not familiar with Jatoba, but since you say it's a dense wood, I'll assume that you feel pretty comfortable with it's weight. Certainly a 9" overhang will be better for your design that the previous 12" dimension.  

I suggest two things- both involve a test of this design. First- have you sketched this our on paper, or with a drawing program on your computer? I use a Mac computer, with Mac software (MacDraft) and I just drew a thumbnail of this design. To my eye, it looks top heavy, and somewhat out of proportion. I am going to try and send it here, but I am not sure the All-Expert's site allows for any graphics in their answers. Anyway, I drew the table with both a 12" and then a 9" overhang, and the 9" looks much better.

(It doesn't work, the graphics would have shown up right here.)


So drawing the design to scale is a big help- visually - for your design. Next, is there any way you can rig some sort of a mockup to text whether it will tip. I have a good friend who is an engineer, and he helps me out from time to time with the physics of some of my designs. So I'm sure he would be able to apply some mathematical formula to this design and say definitively if it will tip of not. The reason I'm saying that is that people solve problems differently. He's a math geek, so he solves it with a calculator. I'm a designer, so I solve it by making a mock up, or testing the design somehow. Is there anyway to clamp up you table, without actually building it? It won't be 100% accurate, because the weight of the wood (both the base and the top) will help in keeping it stable. But what you're testing is more the physics of the table, and whether a 9" overhang will work.

I think making the base bigger makes a big difference in the stability, so if you can do that, combined with the density of the wood, your design will probably be fine. That's about as detailed an opinion that I can offer. I hope it helps you decide about this. I looked in a couple of tablemaking books that I have on my shelf and none of them really address this issue. So it's really about experimentation on your end.

Good luck, you're putting a ton of thought into this, I'm sure it's going to be a nice looking table. One thing- if there's any way to add a little more weight in the table base, by adding stretchers or some sort of design element, perhaps that would counterbalance the large overhang enough to not have to worry about any of this. So you might want to consider adding something- stretchers? spindles?  that will weight it.

Have a look at my website- on the Portfolio page, there are the 2 dining tables that I built that have 12" overhangs. Look at the bases and see how they are constructed. Perhaps if you do something like that, you can go back to your original design of a 12" overhang.

Write back if this doesn't make sense! It's possible, as I've only had one cup of coffee so far today!

Jamie Yocono
www.wooditis.com
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Will,

I'm a little unclear about the inlay, so I can't give you much of an opinion.

Is it wood? Tile? Mother of pearl? Depending on what it is made of, combined with the depth of 5/8" - it might (or might not!) be a problem. Write me back with more detail and I'll try to help.

You know, this is separate from your questions, but sometimes it's really hard to please a customer and yet still be a good woodworker. For example, I had a customer one time who didn't like the look of a thick top. Yet I was making her a pretty large foyer table and I was afraid that making it with a thin top would be problematic. She wanted it so thin, I could barely attach it w/ screws and table top fasteners.

So my solution was to taper the edges of the table top, from the underside. To look at the table, it looked like the top was only about a half inch thick. But when you looked underneath it, you saw that the main body of the top was 1 1/8" thick, and just the edges were tapered to give that effect.

Be careful about following your customer's request (about the base being hidden) too closely. If that table ever tips on them, they'll be the first one's to complain.

There are other ways to camouflage a "country" look to a table. You could achieve this by altering the shape of the legs or the shape (or some design element) in the apron, too.

Anyway, write back with more details and I'll try to help.

Jamie Yocono
www.wooditis.com

Answer
Will,

If I understand what you wrote correctly, everything sounds OK. Take your time with the glue-up, that's one if the areas where things can go wrong. Your inlay can squirt out when you apply pressure to the clamps, or you can apply too much adhesive and have it muck up the top. So be careful with everything and think stuff through ahead of time.

It sounds like you've thought this project out thoroughly, you're on the right track with everything. Now that you've changed the overhang, I think this will work well. Good luck, let me know how it turns out.

Jamie Yocono