How to make an expanding dining table with stored leaves

[Alan S]

You might also want to consider a Dutch pull out table.

[MarkSingleton]

You might also want to consider a Dutch pull out table.

  NOW I know what to call it.  Our dining room table has two 'leaves" that pull out from
under each end. They store underneath the unattached top, which has a 'key' that fits
in a fixed atop the center section of the top of the hay rake base. 

  Which I hope describes what is in that link above.

 Ours is six feet long in base mode.
Each leaf is thirty inches long, so both extended (which we have done exactly once 
since we bought it) makes eleven feet long. 

  Thanks for posting that link, and sorry for the hijack of the thread. Well sorta related
so not much of a hijack!!

[barryvabeach]

Mark,  how sturdy is the table when extended?

[MarkSingleton]

Very sturdy. Never been a problem. There is a bit of a learning curve pulling out the
leaves and putting them back, but it is not bad. Don't know what it is made of, or who
made it. The store we got it from is long gone. No markings on it at all.
But it is very sturdy and well made.

[barryvabeach]

Mark,  thanks,  I am still in the design phase trying to get ideas on how big, and small, I want it to be.

[barryvabeach]

So I finally finished the table. 

    The point of this post is to highlight some of the mistakes in case someone makes something similar.

So I selected a design which I thought was similar to this -   https://www.youtube.com/watch?v=3i-JcDBq3pU, and spent a ton of time watching the video to determine how it worked.  I decided that the leaf rode an a cartridge that was set inside the frame ,  and as the leaf came up, it rode in slots that raised it in the carriage so that it would clear the frame.   I decided i did not like the look of the long cantilever,  and it seemed it could tip if someone sat on it. Also I wanted a smaller table when closed, but I wanted the legs to get further apart so i could fit 3 chairs on each side, and one on each end.  To do that, I built a frame with one visible end with legs attached by mortise and tenons, and on the other end,  each leg was attached to a long rail that was made of birch ply glued up to 1 inch thick, with a skin of veneer on the outside.  The side rails were built as a box, with solid maple on the outside, and birch ply on the inside, and kickers near the top and at the bottom, so that each leg rail fit as a piston inside the box.   It turns out that it was a success, and a failure.  It is easy to extend the legs, and they stay in place when open or closed with a cam clamp set inside the frame, and they easily hold the weight with no sag from the top.  On the other hand, when you pull them out, since the legs are not attached to each other, the table will rack from side to side with any lateral push.  I ended up making it better with a stretcher that gets placed on the legs when they are extended, the stretcher has a rod that goes into each leg to give it some side to side stability, and stores under the carriage carrying the leaf when not in use

   

The sliding part of the table, which is the part that is visible when closed, came out great.  I made an x frame out of 1/2" ply, attached a strip of aluminum stock on each side, then used a table saw to cut a groove in the side of each of the side rail boxes.  The top floats a fraction of an inch above the frame and slides back and forth easily. The x frame is attached to the underside of the top through slotted holes, so that as the width of the table changes with humidity, the x frame will stay the same size.  

   

So the hidden leaf presented the most problems.  I made a number of mockups of smaller sizes, and tried bronze bushings, then nylon, bushings, then finally ball bearings to get the hidden leaf to rise up out of the cartridge.  While I got the profile of the slot okay in the mockup, when I ended up with the full size top ,  it was pretty hard to get it to make the final part of the climb. 

     After putting it in place and trying it a few times,  a friend and I went and looked at the video.  We watched it several times in slow motion, and after a while, we saw that the cartridge moved differently in the video than the way I did it, and realized that instead of the extension part being lifted by the cartridge, it actually rides on rollers set on the rail, and the cartridge just falls away as it is extended.  I rerouted the channels the rollers slide in to make it open,

    ( sorry these two photos show it from the other side, so it looks upside down, in use , the slot goes up as you go towards the end.) put rollers in the end stretcher, and now it works much more smoothly.  Mine does not work as well as the one in the video, because in the video, the visible top, and the hidden extension are both much longer than wide, so when you extend the extension, it is very easy to push down on the outboard end, and the inner end rises up .  On mine,  you need to put a bit more weight, but the leverage is not as much, though it is still easy to do. I put 3/4 black pipe welded to a plate, and screw one assembly to each side of the cartridge and made a u shaped bracket attached to the inside of the side stretchers. When you push the top table out, you lift the leaf and the cartridge tilts very easily on the black pipe, then when the leaf is totally extended, you push down on the part that is outside the stretcher, and the entire cartridge lifts up, the black pipe riding up the slot, allowing the top to clear the side rails.    When you slide it forward, the metal tabs lock into the slots in the top of the legs, and the tenons slide into mortises in the visible top, and that, with the rule joint, makes the hole thing pretty steady.

     
Overall, pleased that I could get a table to go from 4 to 8, with onboard storage of a leaf, but realized it is tough to figure out how something works from a video, and even if I had figured it out, I doubt I would have recognized that changing from a long rectangular top to a more square top would change the leverage factors that were in play.

[barryvabeach]

Closed  -  seats 4

[newzll5]

barryvabeach, looks pretty awesome! Talking of which, here is a resource ( website: https://www.woodroutersreviews.com/best-...ble-plate/ ), where I found Aluminum Router Table Insert Plate. It says that this router table is resistant to rust. Have you tried it, for say it's true? What do you think, should I choose this table or maybe something else from that list?

[jteneyck]

That's pretty amazing Barry.  Doubly amazing for how much effort it took to get there. Congrats for sticking with it.  

John

[barryvabeach]

John,  thanks.  Pretty embarrassed when I went back and looked at the video and said to myself ,  what are those black things in the end stretcher, and realized they were rollers, but in the end it worked out okay.