LumberJocks

Improving this dining table base

  • Advertise with us

« back to Designing Woodworking Projects forum

Forum topic by inexile posted 01-19-2022 08:59 PM 845 views 0 times favorited 34 replies Add to Favorites Watch
View inexile's profile

inexile

19 posts in 1320 days


01-19-2022 08:59 PM

Topic tags/keywords: table base oak woodworking furniture structural

Hi there.

I just completed a mockup of this white oak dining table for a friend. The base itself (what you see from eye level) is what my friend is after.

All components are 1.5×3.5 and the proportions seem fine in the mockup. However, the upper long stretcher and three cross-supports aren’t doing anything to prevent twisting/racking.

Looking for your suggestions on how to stabilize the table without changing the “look” of the base.


34 replies so far

View Aj2's profile

Aj2

4455 posts in 3257 days


#1 posted 01-19-2022 09:09 PM

I would move the parts up at least 7 inches off the floor. I think the table will rock if the floor isn’t flat and it will make cleaning easier.
I would also make the legs parts thicker.
The connection points or jointery leave something to be desired
Good Luck

-- Aj

View Andybb's profile

Andybb

3489 posts in 2063 days


#2 posted 01-19-2022 09:37 PM

^ Agreed. And I’d use c-channel on the bottom if you’re worried about movement unless that’s a processed piece of dimensional lumber.

-- Andy - Seattle USA

View inexile's profile

inexile

19 posts in 1320 days


#3 posted 01-19-2022 10:03 PM

I think the table she’s trying to copy had a steel base. Are you thinking that this joinery won’t work in oak? the base is connected with dominos, and it feels strong enough to me.

View NohoGerry's profile

NohoGerry

59 posts in 169 days


#4 posted 01-20-2022 12:20 AM

Since you don’t list the dimensions of the table top, I’ll take a guess that it’s a good sized table-say able to accommodate 6-8 people at a meal.

If that’s the case, I’d try to persuade your friend to reconsider the base. The way it’s sketched out, people at the table will have a real challenge finding room for their feet-when they pull their chairs up to the table to dine.

If this is in fact an idea from a table with a steel base, it might be that that steel members are narrow enough in dimensions to support the weight of the table without seriously reducing room for feet. But even having said that, the space under the table with the base designed as shown is a little busy looking.

Just my opinion, but if you view lots of dining room tables, the supporting structures are usually designed to maximize the space under the table for either diners feet, or chairs pushed into the table when not in use.

Gerry

View bilyo's profile

bilyo

1550 posts in 2562 days


#5 posted 01-20-2022 02:18 AM

I don’t think that the size of the members and the joinery are adequate to resist twisting and racking. Even if the size of the members increased and the joinery were interlocking, there will be extreme twisting and racking forces that will eventually cause joint failure. I agree that the bottom members laying flat on the floor are going to have issues with the slightest unevenness of the floor. Some adjustable feet are needed.

View Andybb's profile

Andybb

3489 posts in 2063 days


#6 posted 01-20-2022 06:16 AM

Taking another look, in addition to the other suggestions about feet, oak is heavy as hell. If that is 8’ x 44” x2” it’ll weigh in excess of 200 lbs. alone and you can’t rule out that a couple of 200lb men might sit on it. Never seen a dining room table you couldn’t sit on. I think that base has to be metal. A wood base would need to be like 4×4 beefy with a few cross braces under there in both directions and some rock solid joinery and that would ruin the design. Also, those cross braces could also double as c channel.

As far as seating, I think people would have no problem sitting at that table. Maybe even better than most. Your feet wouldn’t go anywhere near the centerline and because there are no legs at the corners 2 people could sit at each end. I like the design because of that.

-- Andy - Seattle USA

View RClark's profile

RClark

291 posts in 3644 days


#7 posted 01-20-2022 11:21 AM

The real test of good design is in how well the piece performs in its intended use. If it looks attractive, but is limited in use because of some unforeseen flaw, then the design isn’t workable.

If it was me, and since the supporting structure members are 1.5×3.5, I think the plan calls for a real mock up using dimensional framing lumber. Pick through the stack at the big box so it will be straight. Put it together; screws are fine for this purpose and then get some chairs and move around it, sit at it, and so on. Use sheet goods for the top.

I’m less concerned about twisting and racking of the top. If you use properly dried stock, I think it should remain flat. Consider bread board ends for the top.

I think those corners could be “tippy” in this configuration. I realize that it would take a lot, but crazy things happen when company comes over.

The floor contacting surface of the supporting structure is very likely to rock at least a little as designed in the drawings. A truly flat floor is a rare thing. I would modify the design to get the long cross members on the bottom up off the floor maybe 1/2 or 3/4 of an inch.

As for joinery, I’d use double bridle joints for the corners of the vertical support structure, half laps for the cross pieces supporting the top, and I’d mortice the two verticals on the long cross piece where they come up to meet the supporting cross member structure under the top.

I don’t have a domino machine, and have never used them. My sense, though, is that I just wouldn’t trust it to handle the joinery in this heavy piece.

-- Ray

View Kudzupatch's profile

Kudzupatch

395 posts in 2668 days


#8 posted 01-20-2022 01:57 PM



The real test of good design is in how well the piece performs in its intended use. If it looks attractive, but is limited in use because of some unforeseen flaw, then the design isn t workable.

If it was me, and since the supporting structure members are 1.5×3.5, I think the plan calls for a real mock up using dimensional framing lumber.

Best answer in the thread!

I to have doubts but there is nothing like testing the idea and seeing it in action. Lot of people do things I never thought would work and odds are it didn’t work the first time they tried it either.

-- Jeff Horton * Kudzu Craft skin boats* www.kudzucraft.com

View bondogaposis's profile

bondogaposis

6183 posts in 3811 days


#9 posted 01-20-2022 01:58 PM

That design depends on a dead flat floor. Something that rarely exists. The corners are not stable either. If someone leans on a corner the table is going to tip. Nobody will be able to sit at the center of the table because the legs are in the way. I would re-design it.

-- Bondo Gaposis

View inexile's profile

inexile

19 posts in 1320 days


#10 posted 01-20-2022 03:21 PM

If it was me, and since the supporting structure members are 1.5×3.5, I think the plan calls for a real mock up using dimensional framing lumber. Pick through the stack at the big box so it will be straight. Put it together; screws are fine for this purpose and then get some chairs and move around it, sit at it, and so on. Use sheet goods for the top.

I m less concerned about twisting and racking of the top. If you use properly dried stock, I think it should remain flat. Consider bread board ends for the top.

Already built the mockup (see my original post). It’s built from dimensional lumber I dressed on the jointer/planer. Their are two dominos at each corner joint with half-laps in the expected places. The base is solid at these joints, but when I put the top on (8’ x 40”) it wants to twist – not stable at all. We’ll rethink the base.

View inexile's profile

inexile

19 posts in 1320 days


#11 posted 01-20-2022 03:25 PM

I think the table she’s trying to copy had a steel base. Are you thinking that this joinery won’t work in oak? the base is connected with dominos, and it feels strong enough to me.


Taking another look, in addition to the other suggestions about feet, oak is heavy as hell. If that is 8’ x 44” x2” it’ll weigh in excess of 200 lbs. alone and you can’t rule out that a couple of 200lb men might sit on it. Never seen a dining room table you couldn’t sit on. I think that base has to be metal. A wood base would need to be like 4×4 beefy with a few cross braces under there in both directions and some rock solid joinery and that would ruin the design. Also, those cross braces could also double as c channel.

As far as seating, I think people would have no problem sitting at that table. Maybe even better than most. Your feet wouldn’t go anywhere near the centerline and because there are no legs at the corners 2 people could sit at each end. I like the design because of that.

- Andybb

Thanks Andybb – great insight. I also agree that the legroom is great here. In fact, that’s the reason my friend chose this design. But I’ll have to rethink the base – it’s just not beefy enough.

View RClark's profile

RClark

291 posts in 3644 days


#12 posted 01-20-2022 03:40 PM


If it was me, and since the supporting structure members are 1.5×3.5, I think the plan calls for a real mock up using dimensional framing lumber. Pick through the stack at the big box so it will be straight. Put it together; screws are fine for this purpose and then get some chairs and move around it, sit at it, and so on. Use sheet goods for the top.

I m less concerned about twisting and racking of the top. If you use properly dried stock, I think it should remain flat. Consider bread board ends for the top.

Already built the mockup (see my original post). It s built from dimensional lumber I dressed on the jointer/planer. Their are two dominos at each corner joint with half-laps in the expected places. The base is solid at these joints, but when I put the top on (8 x 40”) it wants to twist – not stable at all. We ll rethink the base.

- inexile

Ok; when I read (and re-read) your post, I noted that you did say mockup, but since there wasn’t a picture of the physical mockup I took it to mean that it was in drawing only.

-- Ray

View Lazyman's profile

Lazyman

9602 posts in 2847 days


#13 posted 01-20-2022 03:57 PM

I think that the center backbone needs to be much beefier to resist twisting or flexing. If you clamp one end and can flex it at all using some leverage, it is not strong enough. I would also us bridle or finger joints to join the vertical legs to the horizontal base so that you can put a foot or pad there to elevate the horizontal pieces off the floor they don’t act like runners on a rocking chair.

-- Nathan, TX -- Hire the lazy man. He may not do as much work but that's because he will find a better way.

View inexile's profile

inexile

19 posts in 1320 days


#14 posted 01-20-2022 05:04 PM


I think that the center backbone needs to be much beefier to resist twisting or flexing. If you clamp one end and can flex it at all using some leverage, it is not strong enough. I would also us bridle or finger joints to join the vertical legs to the horizontal base so that you can put a foot or pad there to elevate the horizontal pieces off the floor they don t act like runners on a rocking chair.

- Lazyman

Thanks Lazyman. So what if I thicken the backbone to 2” (from 1.5”) and all of the other base members to 1.75” and change from mortise/tenon to a bridle join for the base connections? I also need to raise the cross members so they’re not flat against the floor.

View JackDuren's profile

JackDuren

1858 posts in 2419 days


#15 posted 01-20-2022 05:26 PM

You’ll have to have rubber feet under it for leveling. My concern is the jointer over time..

1/2 lap everything possible and box joint the angled parts

showing 1 through 15 of 34 replies

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com