What kind of joints do you have at the bottom of your end frames and at the ends of your long stretcher?

 

You need to provide dimensions.


George

 

The lower stretcher is a cross lap joint. I’m thinking it will be a dry joint because I want to be able to assemble/disassemble the base in case we move. I’ll maybe put a dowel through it that I can remove at a later point if necessary.

The top supports are attached to the legs with glue and (4) 2.5” wood screws and covered with 1/2” plugs.

The lower cross pieces are connected to the legs with 2.5” pocket hole screws and glue. I wanted that to be a through mortise joint but it’s still a bit outside my skill level.

The top is 5/4 ash, 93.5” L x 43” W

Each of the legs is 3.25” x 3.25”

Top of table will be 30” H

 

I don't know if this would help, but my father built a knockdown/trestle table about 25 years ago, the top is about 7ft long, 3ft wide, with the legs about 5ft apart, and made of 2x6" pine. No direct supports along the top, and is not permanently attached to the legs. It's still flat.

 

Depends on the rigidity of the joinery. If the bottom stretcher is solidly joined so there is no play, and the top is joined so there is no play, then it should be fine. Basically it comes down to the quality of the joinery. I've only built smaller trestle tables but they all had only one stretcher at either the top or bottom, none had 2, and they were all rock solid. But again, I've never built one that size and I think the top will play a significant role.

 

I’m close to beginning sanding on an ash table I’m building based on my own design and a few online photos I used for inspiration (hence no plans to go off of).

Good for you...sounds interesting. I love this style of table and build several traditional versions each year...

My question is do you think I need a piece spanning between the top of the two bases? In other words, another piece running lengthwise that would be fastened to the underside of the top with more buttons.

Usually there is (traditional about 40% to 50% of the time) on those with thin board tops.

I only use joinery...NO HARDWARE...Usually built traditional with only green or "unwaged" wood...and they are always "knock-down" as that is the nature of these tables, design and use context for the most part. They are the tables of the "common folk" and meant be be well used and last generations.

I would (very much) shy away from any "biscuit work" as these have not context in the table, are weak, and only meant for alignment when doing glue up and even then I find them worthless when compared to a toggle (aka free tenon.)

My thinking is this would give the whole base structure extra rigidity if someone were to lean on the end of the table, thus reducing stress on the rest of the base’s joints.

Yes..and if you think you need it (your gutt!) THEN!!! you need it!!!

Feel free to send me an email...I'm on a timber frame project so do see them or this forum much accept on weekends or when I come into town...

Good Luck,

j

 

I’m leaning towards adding a top stretcher and two kickers, similar to this photo

The more I think about it, my cross lap joint is snug but not as tight as I wanted it. Given that I’m assembling during the summer and winter low humidity is around the corner, I worry about racking due to that joint loosening.

Maybe years down the road as my skills evolve I’ll move towards all traditional joinery with no fasteners but for now, this will do job for a big Thanksgiving and Christmas spread!

I’ll try to update the post with updates and final shots for reference.

Thanks everyone for your input.

 

sagging and the braces .......

I think you'll be ok, if you locate the trestles 18-20" in from each end, that's an unsupported span of about 58" max. You shouldn't have an issue with 5/4 ash.



BTW, the angled braces shown will not support the top from sagging.



If you were going that way, I'd be looking at angling the braces off the trestle bottom and angling up toward the middle). With or without a stretcher under the top running between the trestles.

Exactly! Just reverse the braces and angle them up towards the top.
A center spine will help prevent racking if the braces are connected to it. However, that may not be necessary, because the center plank of the top used as the anchor point, will prevent any racking also.

:vs_cool:

 

I think you'll be ok, if you locate the trestles 18-20" in from each end, that's an unsupported span of about 58" max. You shouldn't have an issue with 5/4 ash.



BTW, the angled braces shown will not support the top from sagging.



If you were going that way, I'd be looking at angling the braces off the trestle bottom and angling up toward the middle). With or without a stretcher under the top running between the trestles.

 

Yes I’m not too concerned about sagging. The top is STOUT. But since I’m looking at going this route and the aesthetic won’t change much by reversing the angled braces and I would gain some resistance from sagging, it might make more sense to do that.

I’d never really thought about all the leverage involved in a table before building one of this size!

 

Quick update for anyone following along or considering this for your own creation -

As was suggested above, I went with my gut and added a top stretcher and two angled kickers.

The top stretcher is a lap joint which will be attached to the base with 3 screws.

With two lap joints and the angled kickers there is basically zero play in the base. And I can still take the entire table apart into four pieces if we temporarily need space or move some day.

I’m sure with proper joinery someone could have made this setup rigid without a top stretcher or kickers.

Tonight I’ll be applying Rubio Monocoat finish. Tomorrow night I’ll be attaching the top to the bases with z clips and possibly screws in the middle board.

 

Very nice work!

Quick update for anyone following along or considering this for your own creation -

As was suggested above, I went with my gut and added a top stretcher and two angled kickers.

The top stretcher is a lap joint which will be attached to the base with 3 screws.

With two lap joints and the angled kickers there is basically zero play in the base. And I can still take the entire table apart into four pieces if we temporarily need space or move some day.

I’m sure with proper joinery someone could have made this setup rigid without a top stretcher or kickers.

Tonight I’ll be applying Rubio Monocoat finish. Tomorrow night I’ll be attaching the top to the bases with z clips and possibly screws in the middle board.

Besides looking just awesome, it will come apart for moving! I don't know if there is a way to attach the top without fasteners, but that would be very cool if there was. I have found 2 sided carpet tape to be very "aggressive" so just a couple of strips would work. You just don't want a sudden bump to shift it on the base, especially with a table full of food and dishes. :surprise2:

 

Why rectangles "rack" .....

When you added the angled braces, that stopped the racking. The reason is a triangle will not collapse when pressure is put on the sides or a corner, unlike a rectangle, which will. Put a diagonal brace inside a rectangle and it will not collapse. This forms 2 internal triangles and that why bridge or construction trusses are all made with triangles.


No amount of joinery will replace the angled braces .... unless you use welded steel. :|

 

When you added the angled braces, that stopped the racking. The reason is a triangle will not collapse when pressure is put on the sides or a corner, unlike a rectangle, which will. Put a diagonal brace inside a rectangle and it will not collapse. This forms 2 internal triangles and that why bridge or construction trusses are all made with triangles.


No amount of joinery will replace the angled braces .... unless you use welded steel. :|

Exactly! They made a huge difference.

 

I have never built a table without stretchers or otherwise supports.
I really like the table design in post No.8.
So this leads to the following question:
I know of calculators for joists and other house construction beams. Are there any charts or calculators for span lengths used in furniture construction?

 

I have never built a table without stretchers or otherwise supports.

I really like the table design in post No.8.

So this leads to the following question:

I know of calculators for joists and other house construction beams. Are there any charts or calculators for span lengths used in furniture construction?

I’ve come across something called the Sagulator specifically for shelves but could probably be applied to tabletops. It calculates the sag based on size, span and wood species.

 

Alas the table is done (minus attachment of z-clips). Quite pleased with how it came out and I especially love the buttery smooth satin finish of Rubio monocoat which allowed me to maintain the light color of the wood.

One thing I’m not wild about is how much darker some pieces of wood are than others, specifically the legs. Not a huge deal but something I will like give more consideration for future projects.

 

Great JOb
Looks beautiful and the legs are what they are. Take it from me, I'm a leg man.

Walk through larger furniture stores and you will notice that even manufactured tables dont always have matching legs nor do tables and counter tops always have matching boards. That is what separates the natural from the artificial.

Be proud of your work.
And whatever you do, don't go around pointing out the legs to other folks. Let them see them on their own and they will comment.

 

I recently completed a live edge walnut dining table, 10'x 43", with two live edge slabs for legs. The construction question was the same as yours, how to attach the stretcher for maximum strength. After much consultation and thought, the answer is really kind of obvious. In my case, in order to maximize stability you want the stretcher to be as wide possible between the two legs and the joint to be rock solid. This stands to reason, a 10" stretcher, firmly attached to the legs, will have more strength than a 4" stretcher similarly attached. If the stretcher is attached so it won't move, this will eliminate any rocking of the table end to end.

What i did was to to use draw bolts and a threaded cylinder to mechanically bring the 10" stretcher and two legs in tight as tics. I bored holes horizontally through the legs, match those holes to two horizontal holes in each end of the stretcher and then drill two vertical holes in the stretcher to accept the threaded cylinders. The tricky part is getting all the holes to line up so that the bolt will thread into the cylinder correctly. The best way to do this is to make all the holes a little oversized so that the bolts and the cylinders have a little wiggle room and the threads will bite. You will need some good washers for the bolts, but the threaded cylinders will work just fine in a slighlty larger hole. You will need a way to insert the threaded cylinders into the holes and keep them in place while you thread the bolt into them. My solution was to put a shop magnet on one the end of a drill bit and carefully insert the cylider into the vertical hole until I could get the bolt to bite into the threaded cylinder.

 

...What i did was to to use draw bolts and a threaded cylinder to mechanically bring the 10" stretcher and two legs in tight as tics...

Hi EdS,

That is a very interesting and solid solution within a modern context and application for a table of this size type, though with the challenges you did mention.

However, for the context of actually designing and creating a Harvest-Farm Table in the original context (what many readers are trying to achieve) your solution is out of context as it uses hardware and a "modern solutions" to what was/is more simply and effectively done with joinery alone.

Please note, this is not meant as a criticism in any fashion at all for your work or solution created by you for it. Your resolution for this challenge in the stretcher connection is more than adequate for sure!

I only shared the above for those that want to create one of these fine tables in the original historic context that have functioned as well as they have for millenia, and in knowing it can be down with just traditional joinery modalities just as easily and with no hardware required.