Replies

1. 
   Jamie_Buxton | Sep 08, 2004 01:05am | #1

   Ooo boy, that's a big one.   Opinions...

   * Make sure you understand how you're getting the table from your shop and into its new home.  Building it in one huge piece is probably not practical.   From the beginning, the design should include breaking the thing into smaller modules.   Smaller modules will be easier to handle in the shop, too.

   * I'm a big fan of torsion boxes for objects this big.   They're much lighter than solid lumber, and much more likely to stay flat over time. 

   * A trestle base is a good choice; it naturally dissassembles for transport.   You should consider having more than two trestles.   Using three or four will give you good support for the top, and allow you to break the top into pieces which each bear on two trestles.

1. 
   nohrn | Sep 08, 2004 01:26am | #2

    built a 4' by 10' table that will seat 14 tight.. I built it in one peice.. I made the frame from 2x6 yellow pine bolted together like a pool table . Ithen wrapped a 1x6 oak skirt . I made the legs (only 4 ) from glued up 2.4 covered with 1/4 " oak plywood and bolted to 2x6 fames.

   the top was 3/4 " ply wood , covered with backer board then 16" tile that was left over from the floor. The tile was set in 1x6 border of solid oak, recesed so to was flat.

   Ther is a long span with a lot weight but no sag what so ever. The tile was put on in place and I doubt if I woud ever move it.  If you aare in terested I can send pics. when I get my camer back from repair.  I bought matching chairs. Oak is plentiful for a varity of additional peices. Have matching oak buffett also.

1. 
   Buzzsaw | Sep 09, 2004 05:43am | #10

   Bob,

    I am not the original poster of this thread but would love to see the picture of the table top.  I am currently building a kitchen island and the top is going to be 3/4" plywood, then backer board, and my wife is going to tile it since she is the expert on tiling.  I am interested in your oak border and how it looks.  Did you router it with a roundover of chamfer bit?  A picture will tell the story.  Thanks.Regards,

   Buzzsaw

2. 
   Elcoholic | Sep 08, 2004 02:33am | #3

   The length sounds a little tight for 7 arm chairs on a side.  The rules of thumb are 30" for arm chairs and 24" for side chairs and 42" wide.  If you put one person at each end then you need 6 on a side at the required spacing between the trestles.  The overhang at the ends can be as little as 16".  This also reduces the span between trestles.  Some folks (like the Shakers) locate the stretcher pretty high, but the geometry and strength is better if it is lower.  I would build the top as one piece if at all possible, the extra joints in a modular approach will never line up or look as good down the road when the veneer chips.  I'm not a fan of veneered work, but you may not have a choice due to the weight.  I haven't read his book, but based on his postings here and a trip to his web site I'd expect you find some good info in Kim Carlton Graves's table book.

   John O'Connell - JKO Handcrafted Woodworking

   The more things change ...

   We trained hard, but it seemed that every time we were beginning to form up into teams, we would be reorganized.  I was to learn later in life that we tend to meet any new situation by reorganizing; and a wonderful method it can be for creating the illusion of progress while producing confusion, inefficiency, and demoralization.

   Petronious Arbiter, 210 BC

3. 
   JohnWW | Sep 08, 2004 03:16am | #4

   Peter,

   This would be a natural for Shaker style, their tables had to seat dozens and yet they were graceful and not at all institutional looking. 

   Consider building a plank top that could be separated into three or four long planks that would be easier to deliver.  You could use draw bolts, recessed into the plank's bottom face, to pull them together for tight joints.

   Your base structure will be the source of stiffness for the top, even a thick top spanning an unsupported 10 feet would be flexible, the top will at least need a center stretcher, which was commonly used in Shaker design.

   A good place to start would be Chris Becksvoort's book, "The Shaker Legacy", or John Kassay's "The Book of Shaker Furniture".

   If you haven't built and veneered torsion boxes already, a piece this size is not the place to start, there's quite a learning curve.

   John W.

4. 
   pauldowns | Sep 08, 2004 04:26am | #5

   The actual length of the table required will be determined by the size of the chairs. One of the other respondents mentioned 30" per arm chair and 24" per side chair, but you can squeeze 14 into a smaller table than those dimensions would suggest. To determine the correct size of this table, you need to know:

   1. The dimensions of the room. If the table is to seat 14 at all times, then any edge of the table should be no closer than 36" from the nearest object (wall or furniture).

   2. In what situation will seating 14 be required. Is this every day, every week, or just family holidays? Families are generally willing to be seated very tight, in which case 22" per side chair would work. You could have a table that is 54 x 120 and seat 14, but it will be tight. If the client wants COMMODIOUS seating for 14, then 24" per side and 30" per arm is about right and the room should be at least 20 feet long.

   We have made many tables this large or larger, but here is one that was specifically designed to seat 14. It is 54 x 144, swells to 60" wide at center:

   http://www.shop.pauldowns.com/OTDries.html

   3. Construction. Don't even think of making the top a single piece. You'll regret it. Making it in two halves is feasible. A sturdy pedestal will work, but make sure that it is extra chunky. If all 14 people decide to lean forward and put their elbows on the table at the same time, you just added a half ton of weight to the top. Torsion boxes are a lot more work than 8/4 maple, but the solid will weigh a lot. And you will have to flip it several times when finishing, so if you don't have a helper than the torsion box may be the way to go.

   4. Make sure that it will fit in whatever vehicle you plan to use to move it. Get help when lifting the top in the shop, or you could blow out your back.

   5. Good Luck!

   Paul Downs

1. 
   jptenberg | Sep 08, 2004 06:57am | #6

   Paul--

   Thanks for your input.  I looked through your website, and I must say that you have some amazing work represented there!  With regards to the larger tables, what type of substrate are you veneering to?  I have done a fair amount of veneering designs on smaller tables, and have always used 3/4"mdf as a base, but for something of this size would it be better to try a torsion box with 1/4" mdf skins?

   Also, do you think that it would be better to break the top into 2 pieces or 3 to achieve the 14 foot length?

1. 
   pauldowns | Sep 08, 2004 05:32pm | #7

   We usually use 3/4 mdf for substrates, but depending on the size of the table we might make a torsion box. Make sure that your client is OK with veneers before starting on this - some people won't accept them. On our larger conference tables we make a sandwich of 3/8 mdf, 3/4 birch, and 3/8 mdf to make the top more massive - and then we help each other move the pieces around.

   It would probably be easier on you to break the top into 3 pieces, and would look better to make it in 2 pieces. It really depends upon whether you want your own convenience to override the satisfaction of the client in the long run, although the client may not know or care the difference. And are you sure that the table needs to be 14 feet?

   Paul

5. 
   robkelly | Sep 09, 2004 01:48am | #8

   Your client wants massive and  a 14' x 2" plank will not look or feel massive. In the Renaissance, a table like this would have 3 trestles, but was built for function, not looks. The top you plan would in hard maple weigh about 400 lbs. 3 or 4 people can handle it. MASSIVE would be 16/4, but weigh 800#. 44" is an unnecessary width. 40" is plenty wide for diners facing each other, it leaves enough room for candelabra and condiment dishes, but if your client is thinking of tureens and platters on the dining table, rather than serving from a side table, 44" may be too narrow.

1. 
   pauldowns | Sep 09, 2004 04:43am | #9

   Rob -

   40" is way too narrow for modern banqueting. 16/4 stock would only leave 26.5" of legroom - not enough for many armchairs. People mean different things when they say "massive" and the OP should really ask the client about what he/she had in mind. You are correct regarding medieval practices, but on the other hand why stick to that level of development? We live in a different world, and our easy access to power equipment gives us different options regarding design and construction. Clients have different expections and will use the table very differently than in medieval days (no servants, for one).

   Paul