What is the best method for attaching metal legs to a large porcelain slab for an outdoor dining table, such as gluing wood to the bottom for stability?
Asked by Volkan Kumcuoğlu 
3 months ago
Last Updated: September 30, 2024
I have this huge 4ft by 10ft porcelain slab that I want to use as the top for an outdoor dining table. I’m considering getting some metal legs (check out the photo). How do you think I should attach the top to the legs? Should I stick a big piece of wood to the bottom of the porcelain and then screw the legs into that? Does that plan make sense to you? If it does, what kind of wood should I use? Any other tips? I’m pretty new to this, so please go easy on me. Thanks!
If the slab is heavy, you could try using silicone. It’s similar to what they use for stone countertops. Avoid using mechanical fasteners unless there is room for the materials to expand and contract.
I have experience with putting granite on wrought iron frames and simply using silicone for the attachment.
Wow, that is stunning! Where did you get such lovely porcelain?
Do you know the thickness of the stone? Porcelain can be delicate when laid flat and might need a support underneath.
I’ve seen a slab with raised mitered edges and plywood underneath the whole sheet, it appears to be about 1.5” or 2” thick from the side.
The slab is 1/2 inch thick. I’m thinking of adding 3/4 marine plywood underneath for extra support. Do you think that would be sufficient?
Yeah, I agree that sounds like a good plan. It might be helpful to consult with the stone supplier just to be sure.
If you’re planning on using plywood, I think galvanized deck bolts should work well. Maybe consider a strong adhesive to secure the slab to the wood.
The majority of people have recommended using silicone to bond porcelain to the plywood. Some have also suggested creating holes in the plywood for easier detachment.
That’s a little beyond my area of expertise. You’d need a really strong adhesive specifically made for that. You definitely don’t want it to fail with such a heavy slab.
Make sure your frame is sturdy enough to hold that big slab. I recommend using silicone acetate to attach the stone to the base. Best of luck!
How about applying silicone to attach the slab to the frame? It would be super sturdy and you would have to scrape it off (the silicone) to disassemble it. Similar to gluing wood to the slab first, just skips the wood.