# Cast Iron Table legs to Slab wood Table top



## Slade (Nov 14, 2018)

My first time posting, but I've always found helpful advice to questions when reading others posts. Take it easy on my drawing skills, as i'm just learning sketchup. So I'm building a slab table. Its a large slab of Sycamore. 30-35"W x 100.5"L x 2.1/4"D. I did a epoxy finish on the table and i think it look pretty slick. My concerns are with the legs. I have some cast iron wishbone legs that i'd like to use for this beast. The top plate of the Legs are 12" x 5 1/4" with four holes in them. Do you think this is a large enough plate to simply recess into the bottom of the wood and i'd be safe from racking? I've attached a 'default' picture of what this would look like.










Since I'm not sure if that would be safe from racking, i was toying with the idea of making a larger top plate that i would weld four bolt shafts at the same locations as the 'default' top plate. This way i could attach the legs to the larger top plate. I would also epoxy the 'new' top plate into a recess thats routed out and then screw it in to the table top. I think this would serve two purposes. one is to make it more sturdy and two would make it easily movable in the future as i could just remove the four bolts and the legs will come off.



















If thats still not enough to prevent racking an additional thought i had would be to run a horizontal 1/4"x4" plate connecting the two new top plates and recess that as well.

Any advice would be appreciated.

Slade


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## bilyo (May 20, 2015)

I think your Sketchup drawing is just fine. Better than I could do. My gut feeling is that your top plate connection to the table will be OK. My gut also makes me more concerned about the top plate connection with the vertical leg member. I wonder if this and the vertical piece will be strong enough and stiff enough to resist flexing, table wobble, and maybe failure. At the least, I wonder if some gussets at that top connection and a stretcher between the two legs would be advised. You might find someone who can do a structural analysis based on the strength of the steel (did you mean cast iron or wrought iron?) and the welds.


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## 000 (Dec 9, 2015)

The way it is may be OK but not great. Attached with some 1/4" or 5/16" lag bolts.

If you could weld or bolt a separate plate turned sideways, it would be more help with the racking.


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## Manitario (Jul 4, 2010)

Adding more bolts or larger attachment plates probably won't help with the inevitable racking the table will experience. The wood is going to fail long before the hardware will, and even with larger attachment points, you're expecting them to deal with a large amount of force. This would be fine if it was a coffee table but I'm not sure how it'll stand up to 20y of big uncle Jim slamming his gut into it at every family dinner.


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## Slade (Nov 14, 2018)

Thanks guys. The legs are cast iron depicted below. Thats why I'm going the bolting on route, as i dont think welding to cast iron would work out.










I was caught up on extending the top plate i didnt think to run it sideways instead of the same direction it was running.

So JBay, if i went your route, would i need to mess with running a piece between the two plates, or do you think just the bigger plates turned sideways would suffice?

Manitario, whats the best option to reduce the racking so it would last with big uncle jims gut upsetting my bulid? lol. Would welding two 4" wide 1/4 thick plates on each end of the plates fix this? That way the legs are reinforced by the these two cross bars, that i could also recess and bolt into the tabletop.

Maybe something like this?









Man its so nice to get some feedback, i appreciate it. This stuff keeps me up at night!


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## Phil32 (Aug 31, 2018)

One question that has not been raised is the actual weight of the slab top. The 2-1/4" thick slabs of sycamore that I've dealt with are fairly heavy, depending on the moisture content.


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## Unknowncraftsman (Jun 23, 2013)

Those are really good looking table legs.
I would mock the whole thing up with just the minimal amount of fasteners to see how much wobble there is.
My gut tell me you will not get a ridged table without adding a brace from leg to leg. This is your chance to be creative. 
Go back to where you found the legs with a open mind and look around.
Good luck


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## AZWoody (Jan 18, 2015)

I would probably slot the holes side to side to allow any wood expansion or contraction. Will help in preventing some cracks or warping of the wood as the seasons change.


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## Slade (Nov 14, 2018)

Its about 200lbs and ~10% MC. Noted on the slots side to side.


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## NormG (Mar 5, 2010)

Gorgeous legs. Maybe a 3 inch by the width of the legs, with bolts going through the leg. You place it wherever you think it looks the best


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## bilyo (May 20, 2015)

Those are indeed handsome legs. I agree with Aj2, I think you definitely need a brace from leg to leg. Or, you could also place an angle brace from about the midpoint of the vertical part of the leg up to the table top at about a 45 to 60 degree angle. Especially with the larger top plate, I don't think there will be a stability problem form side to side. But, from end to end, it will not be rigid enough without additional bracing.


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## Slade (Nov 14, 2018)

Thanks for all the feedback, I think i'm going to try for the below setup. Two sheets of 12×24 1/4 plates recessed, epoxy'd and screwed in and connected by a welded on 4×49 1/4 plate. I'll then conect the legs with 4 bolts that are welded onto the 12×24 sheets. "Hold my beer" I'm goin for it.


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## Knockonit (Nov 5, 2017)

me thinks, a rod drilled thru the web in lower legs, threaded, with deco nut on outside, and stop nut on inside might look decent, giving legs some stability, just an idea. not sure if it will solve the shake and possible bake issue.
Rj

or bend an rod and still thread thru legs at web and turn up to under slab and connect, this for srue would give table some solidity


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## bilyo (May 20, 2015)

I think your plan will not give you the longitudinal rigidity you need.


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## Slade (Nov 14, 2018)

so i have to have another cross bar if i want this sucker to last and not fail, is what im hearing? something like one of these two options?

rough bar all the way through 









or 45-60 deg angled brackets?


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## bilyo (May 20, 2015)

That's the idea. However, neither would have to be connected to the legs that low down. For instance, your angle brace could be maybe 6" to 8" down from the top. Actually, a combination of the two will give the most rigidity. If you do that, the triangle at the top could be even smaller.


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## Knockonit (Nov 5, 2017)

you could also do a arch type piece to mimic the main feet, connect at legs somewhere, and at top of arch at bottom of top. Sorta like a trestle, but out of round stock 
just another idea
Rj


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## bilyo (May 20, 2015)

> you could also do a arch type piece to mimic the main feet, connect at legs somewhere, and at top of arch at bottom of top. Sorta like a trestle, but out of round stock
> just another idea
> Rj
> 
> - Knockonit


Good idea. It solves the structural problem and would be aesthetically pleasing.


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## Slade (Nov 14, 2018)

I like the round stock idea. Now i need to figure out how to attach the round stock to the legs as welding to cast iron, i dont think would be a good idea. I'm liking this idea more and more. It'll all flow together much better i think.


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## EEngineer (Jul 4, 2008)

I recently did something similar for a sander table for the shop. It will eventually hold my disk sander and the oscillating spindle/belt sander. I'll post final pictures when I finish.

The old cast-iron legs came from a Deming ironing machine. Same problem - racking. My solution was this:



















From the picture you showed of the cast-iron legs, I would place a nice piece of round stock (diameter as big as you can fit in that thinner web cast in the legs) and drill a couple of holes for lag bolts in each end. (two lag bolts each side to prevent turning). Finish to match the top.


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## ocean (Feb 13, 2016)

The cross bar between the the two legs will give you the support your looking for. I like what Knockonit says. Arched bar attached to legs with thru bolts drilled in cast iron legs as well as attached at the contact spot under table top. Go to a welding / metal shop for fabrication and see what they can do for you. Will cost you but they can do it right.


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## Knockonit (Nov 5, 2017)

drill a hole and put an acorn trim nut on the threaded part on outside edge, lotsa work, but once done will look great. Not easy, but not everyone would go to the trouble either.
best of luck
rj


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## bilyo (May 20, 2015)

> I like the round stock idea. Now i need to figure out how to attach the round stock to the legs as welding to cast iron, i dont think would be a good idea. I m liking this idea more and more. It ll all flow together much better i think.
> 
> - Slade


You could have a piece of flat stock welded to the ends of the arched round stock and bolt that to the leg. Or, you could have a bolt welded to the ends of the round stock at an angle that would be perpendicular to the leg and pass through a hole you drill through the leg web. Finish with an acorn nut.


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## Slade (Nov 14, 2018)

Thanks all. I'lll post some pics when i finish. really appreciate all the feedback and suggestions!


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## Jim Jakosh (Nov 24, 2009)

I think if you had a support gusset that attached to the vertical part of the leg just above the curved bottom and then go up at a 45 degree angle and screwed in at the top, you will have a very sturdy table. Those plates across the underside of the top will not give enough rigidity. You need a longer moment arm to counteract torques that you can get from the bottom end of the leg.

That second option you showed would do it.

Cheers, Jim


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## Slade (Nov 14, 2018)

Took some time, but i finally finished it up. thanks for all the feedback.


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## SMP (Aug 29, 2018)

I personally wouldn't do the angle brace. Kind of reminds me of folding tables. I'd do the long straight run. Probably black iron pipe for what i think would go well. Very cool legs.


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## bilyo (May 20, 2015)

That is one beautiful table. Good job. The legs are just perfect. The top looks like it is floating in space. And, look how deep the finish is. Wow!


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## JerryBa (Mar 10, 2019)

Seems as though the racking could be handled easily with a t brace with a leg length of 12". Screw pattern of four grouped on the end. With two to provide lateral support near the t.


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## JerryBa (Mar 10, 2019)

Absolutely beautiful table, congratulations !!


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## Snipes (Apr 3, 2012)

That's a nice piece of wood!! Nice work. What are the dimensions?


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