# Structural design



## Perfect45Degree (May 16, 2011)

Hello all,
This is an update to my original questions about my table design for a thick top dine table:

Here is my table I call Mondrian Inspiration. I removed beams from my home to make more room for my shop. He, he! Milled to discover beautiful clear grain in most. I laminated the ones with knots with cvg pieces taken from the good beams.

Inlaid with Walnut and Cherry.

This is incredibly strong. I made a through spline one each end and created a bolt system holding the ends on. The legs are removable. I made steel plates and mounted them to the tops of the legs, threaded inserts into the table top. The steel plate is recessed and supports the body of the table as well.This has worked out perfectly as the top of this table is incredibly heavy! Moving it to a trade show, the shop, and back has told me exactly what I needed to know about having the legs be removed.










The plugs on the ends are removable access to the threaded rod and bolts. The rod is about 16" long and runs down the center of the 2 1/4" thick top. I anchored the rods with washers and nuts embedded in epoxy. The channel the rod sets in allows it to move back and forth as the main body of the table expands and contracts. The breadboard ends are glued on in the center only, then the spline and these bolts hold it to the table and in alignment. I made the interior of the breadboard end slightly curved so that when I glued on the pieces they would be compressed at the outer edges of the top. Everything worked like a dream. It is solid as a rock. Looking like it will indeed last generations.

Thanks for the input! This is such a great group of people to share ideas with!


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## SPalm (Oct 9, 2007)

Ummm. I understand the question, but what do I know. It seems like your rendering has a minimal skirt. I like that both for beauty and strength. I would vote for permanent, with such a small skirt.

Does the leg actually go through the top as in the picture? Or is that just an illusion. I would think that you do not want it passing through the top.

Are you just playing with leg ideas? I like the one in the front - used on all four corners.

But what do I know?
Steve


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## CharlieM1958 (Nov 7, 2006)

I really don't see an advantage to removable legs. Moving a table with fixed legs is rarely a big problem, and how often do you plan to move it anyway? With such a minimal skirt, I don't think bolt-on legs would be as stable as one would like.


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## BillWhite (Jul 23, 2007)

I would use a skirt and fixed legs. Mortice and tennon for sure. If not M&T, dowels for sure If ya want it to be minimal, maybe a laminated thick and narrow skirt that will be rigid (ply between solid woods). Kinda like a glue-lam joist. Also consider a cross member in the center of the table. Won't be visible, but sure will add to the stability.
I build lots of tables, and I feel that the skirt adds so much to solid "feel" to the table. Don't want mine to act like a drum top. Tap it. If it resonates, it ain't solid.
I also use table top fasteners (the "z" shaped metal clips"). They'll allow the top to move as the moisture changes.
I like the design, and the different styling on the legs adds to the feel of the piece.
By the way, it is "tennon". Tendons are in your arm as you sand your a$$ off (my humor for the day).
Bill


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## shipwright (Sep 27, 2010)

Hi Jacquelyn,
I actually like the Idea of having no apron and fitting the leg up into the top with or without a brace at the innermost corner. With a 2" thick top and 4" square legs you could, with a step or two in the mortise, have a massive glue area. Of course you would glue it with hide glue for greatest strength and then if it ever did fail it would be an easy fix. I do think however that it would take a nasty fall off a truck to break it.

I know I didn't directly answer your question but I just wanted to cast a vote for your first, original idea.


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## tinnman65 (Jan 19, 2009)

I might be in the minority with this opinion but I feel that a breakdown table would not detract from the overall quality of the piece, If it is well made no one will know the difference. I sure would not want to move a 42" x 88" table with a 2" thick top without removing the legs. I have a high end factory produced dining room table that is rock solid and has removable legs, and I can assure you I'm very happy of that fact, and it doesn't have a 2" top! "I associate break down work with lesser quality" I remember that was once said of furniture that had veneer on it and we know that's not true. Whatever you chose to do I look forward to seeing it when its done!


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## Sawkerf (Dec 31, 2009)

I wouldn't try this on a table that will get a lot of use and abuse - and a dining room table gets plenty of both. You're trying to keep everything solid with only two inches of glue surface and ~28" of "lever" that will be wanting to pry it loose.

This might be neat for something like an end tble that doesn't get a lot of pushing, but it probably isn't best for a dining table. Those skirts are there for a reason. - lol


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## a1Jim (Aug 9, 2008)

Jacquelyn I think this is a very interesting design. If it was something a client of mine wanted I think I would encourage them to ad an apron for structural reasons. If you minimize the apron to much it will also minimize it's value as a structural member. I think it may be ok with out the apron but that's why I would include an apron is that it *May* be ok. If you decide to have removable legs an apron is even more important. I think there are a great number of valuable tables that have legs that are removable.


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## Perfect45Degree (May 16, 2011)

Thank you everyone who piped in! I have received advice and opinions that basically cover each option. On my drive this morning I realized that I really don't want an apron around the table and then it hit me that I made "Bob's Desk" with nothing like that. His desk is bolted to the wall at one point which adds tremendous strength but it is many hundreds of pounds heavier and before I bolted it to the wall it was very sturdy with the three legs. Anyhow, I realized that I can do a similar attachment which will be able to be removable and I believe it will be plenty strong. I'll post pics of the process as I make it this week. Basically I think I will make steel plates that recess into the top and bolt to it using threaded inserts. The steel plate will have a large post which will go down the center of the leg and set in epoxy.
I feel very convinced that this will work and after just experiencing this "ah ha" moment I'm pretty certain it is the path I will take. However, I reserve the right to change my mind as I seem to be doing with this particular question.  Please feel free to share your opinions with me and especially if you have any particularly good "ah ha" moments yourself!
Back to work . . . .


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## LeeBarker (Aug 6, 2010)

I'm having trouble with the apparent lack of elegance in the steel plate-and-post idea. Even though it doesn't show, it troubles me.

There are other ways to do it, discussed here, that will have more of your hands and your soul in the product.

Just my $.02.

Kindly,

Lee


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## Perfect45Degree (May 16, 2011)

Thanks for your two cents! I appreciate it. I think metal and wood can go together and the way I will shape and finish the metal will be fitting. I've been contemplating bringing the metal into other aspects of the table for continuity but the expansion and contraction issues have backed me off of the idea. I'm still thinking about it. There are a lot of people combining these materials right now. For me the trick will be to do it with integrity. I realize not everyone will always be pleased with my decisions but I have to do what feels right to me and follow my own path. Keep on sharing your views with me though . . . it's great to hear from you all!


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