Thread: Advice needed on a big/heavy table. Help out a first timer :)

Unless you can't actually move the components, I say go for it. A few things that come to mind for you to consider:

You may need some sort of bracing across the width to stop it from sagging under its own weight and to keep cupping in check. I'm thinking along the lines of 25x25x3mm L-section steel screwed into routed grooves with slots (rather than holes) to allow for movement around the screws.

Assuming 550-600mm across the top of the stump, you'll have about 450mm overhang on each side which may give you stability issues (there's always someone who sits on the edge of tables), especially if you're just sitting the top on locating dowels with no fasteners.

You could probably use epoxy to fill voids and stick back any bits that fall out of the heart during milling.

Maybe look at sandblasting the stump clean? No idea how much it'd cost, but at least it would stay dry. A wire brush head on an angle grinder is also a fast way to chew through bark and rot without damaging the healthy timber; I did it a little while ago on some redgum, it vaporized the crappy bits but the solid part had nothing more than some friction burning. Full protective gear (face shield, breathing gear, etc) is, of course, a MUST with this method.

Originally Posted by elanjacobs

You may need some sort of bracing across the width to stop it from sagging under its own weight and to keep cupping in check. I'm thinking along the lines of 25x25x3mm L-section steel screwed into routed grooves with slots (rather than holes) to allow for movement around the screws.

Assuming 550-600mm across the top of the stump, you'll have about 450mm overhang on each side which may give you stability issues (there's always someone who sits on the edge of tables), especially if you're just sitting the top on locating dowels with no fasteners.

You could probably use epoxy to fill voids and stick back any bits that fall out of the heart during milling.

Maybe look at sandblasting the stump clean? No idea how much it'd cost, but at least it would stay dry. A wire brush head on an angle grinder is also a fast way to chew through bark and rot without damaging the healthy timber; I did it a little while ago on some redgum, it vaporized the crappy bits but the solid part had nothing more than some friction burning. Full protective gear (face shield, breathing gear, etc) is, of course, a MUST with this method.

I did have concerns about it's own weight being an issue, I guess my having a more traditional leg design with frame this wouldn't be an issue. The stability concerns I had prompted my to consider getting the stump cut in two and then spacing them roughly 600mm to give more support.

Hadn't thought using epoxy to rejoin like that would yield a decent result, but thinking about it more now, why wouldn't it!

Sandblasting is not a bad idea at all, I'll look into it. I've used the steel brush technique before, and couldn't agree more about the protective gear. The look I'm really wanting with the stump is the aged grey/silver dried hardwood so I'm unsure if in order to achieve this I need to actually leave it out in full weather. Any ideas?

You can still use the stump in 2 halves if you incorporate a frame. I'm thinking hardwood, 80-90mm high and 35-45mm thick, glued and dowelled together (3 70x12mm or 4 50x10mm per join should do) then have a slot in the top of each half stump for the frame to fit into and fix with 3 150mm long coach bolts in each end and screw up into the table top (go for 25-30mm penetration in a 40mm top). Something like this:
IMAG1291.jpg
I'd go for about 350mm setback from the sides and 600mm from the ends. That will control both flexing and stability all in one hit without being visible unless you're standing a long way back.

Not sure about the weathering. Leaving it to weather naturally could cause it to crack/split. Maybe have a look at chemical ageing? I'm sure there are recipes out there that use readily available or household chemicals.

Originally Posted by elanjacobs

You can still use the stump in 2 halves if you incorporate a frame. I'm thinking hardwood, 80-90mm high and 35-45mm thick, glued and dowelled together (3 70x12mm or 4 50x10mm per join should do) then have a slot in the top of each half stump for the frame to fit into and fix with 3 150mm long coach bolts in each end and screw up into the table top (go for 25-30mm penetration in a 40mm top). Something like this:
IMAG1291.jpg
I'd go for about 350mm setback from the sides and 600mm from the ends. That will control both flexing and stability all in one hit without being visible unless you're standing a long way back.

Not sure about the weathering. Leaving it to weather naturally could cause it to crack/split. Maybe have a look at chemical ageing? I'm sure there are recipes out there that use readily available or household chemicals.

That's a good idea, hadn't thought of recessing the frame into the stump halves, certainly a way to make it as low profile as possible. My only drama with screwing into the top is I really wanted to make it so the base and top could be separated and then put back together easily and without damage. It'll be so hard to move as two pieces. I guess each time it's moved could move the screw points. Would screwing as you mentioned cause problems with restricting movement?

Thanks for the detailed response

some comments on the size of your table

a live edge dining table measuring 2800mm x 1500mm and 40mm thick

a table that size will require a space about 4500 x 3500 to allow people to move around people seated at the table -- do you have this space?

2800 x 1500 is more a conference than a dining table

a "standard" place setting is 600-700 wide and 300-350 deep
a table wider than about 1000 presents difficulties for passing items (the salt and pepper) across it and also holding conversations.

Originally Posted by ian

some comments on the size of your table

a table that size will require a space about 4500 x 3500 to allow people to move around people seated at the table -- do you have this space?

2800 x 1500 is more a conference than a dining table

a "standard" place setting is 600-700 wide and 300-350 deep
a table wider than about 1000 presents difficulties for passing items (the salt and pepper) across it and also holding conversations.


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This table is really being designed based around my parents building a new home when they retire and they've assured me they'll make the space. Agreed it is certainly large, it's only slightly larger (wider) than the table we grew up with and we always found it frustrating trying to get two people on an end. You'd end up straddling a corner or something, this was also a driving reason behind using the stump for a base to eliminate the corner leg issue. We do have a large family and once you add on significant others you quickly have over 10 people. I guess the exact dimensions don't have to be settled now, I will be constantly checking with them to make sure they want that size

To clarify something else- I'm counting on milling the slabs at around 50mm in order to get 40mm finished. Does this sound right? Too much? Not enough?

Originally Posted by JackAttack

That's a good idea, hadn't thought of recessing the frame into the stump halves, certainly a way to make it as low profile as possible. My only drama with screwing into the top is I really wanted to make it so the base and top could be separated and then put back together easily and without damage. It'll be so hard to move as two pieces. I guess each time it's moved could move the screw points. Would screwing as you mentioned cause problems with restricting movement?

Thanks for the detailed response

How often are you planning on moving it? You should be able to re-use the screw holes many times without stripping them, just be sure to pre-drill them or you'll end up snapping screws off half way in. An even better way would be something like this:

Make dimension 'b' 1-2mm smaller than 'a', the tongue on the block should be a snug fit in the groove.

Originally Posted by JackAttack

To clarify something else- I'm counting on milling the slabs at around 50mm in order to get 40mm finished. Does this sound right? Too much? Not enough?

Can't say this with any authority, but I reckon you need to go thicker to allow for movement as the slabs dry. Maybe 60mm?

Hope your parents plan on having one wall of the new house open up - something that big is going to be.....interesting to get onto place if it has to go around corners, up or down steps or through doors.

One amusing sight sticks with me over the years - about a dozen very big Pacific Islanders trying to get a big slab table top up a set of stairs at a convent - they got stuck at the second turn in the stairs and all stood around head scratching, no going up or down. I had to attend to other work so I never did find out how they managed - or didn't.

If it were me ...

I'd be looking at an extending table about 900 wide sized to seat 3 each side plus one on each end (total 8), that could be extended to accommodate a further 6 diners (total 14). There are designs that incorporate an extending frame and two leaves that stack on top of each other. The "base table" would be about 2400 x 900, extending to 4800 x 900.
The advantages would include easier to move into and out of the house, and the room iot would live in would be easier to build and configure than a squarish rooms.

I'd be looking at the top being no thicker than about 30mm -- mainly because I think 40mm and thicker tops look too heavy.

also, a 30mm hardwood top shouldn't sag under it's own weight -- but if you are concerned it might, a strut down the centre would be sufficient

2400x900 would look a bit narrow and 4800x900 is going to look downright silly. You have to keep the width in proportion to the length or it's going to look wrong. A dining table that long should be a grand piece of furniture, not a line of trestle tables. Sorry to be so blunt, but I can't let that one go.

On a 2400 long table I'd say 1000 is the minimum width, probably go for 1050-1100, 3m and over in length should be 1100-1250 wide and over 4m long should be at least 1200 wide.

Originally Posted by elanjacobs

2400x900 would look a bit narrow and 4800x900 is going to look downright silly. You have to keep the width in proportion to the length or it's going to look wrong. A dining table that long should be a grand piece of furniture, not a line of trestle tables. Sorry to be so blunt, but I can't let that one go.

understand your thinking

but a grand piece of furniture needs a grand room and accompanying grand pieces like chairs and sideboards, etc.
if the table will be used daily by mum and dad, most of it's length would just be a giant dust catcher -- perhaps best left under dust covers till the family assembles for special occasions.

with significant others the OP is already looking at over 10 diners, add in a few kids and the number of diners is approaching 20.

For that number the table in Government House Sydney wouldn't be out of place -- but that one has removable leaves.

Originally Posted by elanjacobs

On a 2400 long table I'd say 1000 is the minimum width, probably go for 1050-1100, 3m and over in length should be 1100-1250 wide and over 4m long should be at least 1200 wide.

After having a bit more of a look and play with a tape, I'm thinking the 1100-1200 is a more sensible width. I'm not really wanting to go below the 1100, as stated once you factor in us kids having our own kids + other guests it very quickly approaches 20 people.

Got the timber milled monday, and moving it to it's home (at least for a few years while drying) at my place. The double handling of stacking it once and then unstacking it, moving it and re-stacking it isn't ideal but, whatcha gonna do? Hoping I've got my drying principles/rules right, it'd be a real shame to come out with bendy boards (albeit unlikely with ironbark)

Good idea, 1500 sounds big but when you actually have it in front of you it's bloody huge. There's a 2700x1500 table sitting at work at the moment and its a bit ridiculous.