Concrete tabletop

[markw]

A tabletop made of reinforced concrete.

• The project
• More inspiration for your table project

The project

I did a bit of research to find suitable materials for this project, which was to make a concrete top for my table. Here's a quick overview that others can hopefully find useful. 

To make the form, I used this melamine. This is the concrete I used and this is the reomesh. I used WD-40 water protective silicone to ensure no sticking to the form. This is the silicone I used for rounding the corners of the form. I used this silicone scraper set for rounding the silicone in the form. 

I cut the pieces of melamine and I made it so the concrete will be 40mm thick. The size was 2 x 1m. I needed 8 bags of concrete for this size.

Then I screwed the sides on. Then I ran a thin bead of the silicone around the edges and rounded them using the scraper set. This meant the corners of the tabletop would be nicely rounded.

Prior to adding the concrete, ensure the melamine is clean, then spray all over using the silicone spray.

Mix up the concrete according to the instructions on the bags. I had to add an extra couple of hundred mls of water to what it said to get it a nice consistency. Fill the form up ½ to ¾ with concrete. I left the edges a bit longer so it was easy to grab onto to pull them off later.

Then you'll want to vibrate it a lot on the sides and bottom. I used a reciprocating saw with no blade in it and ran it around the sides and underneath for about half an hour. You will see all the bubbles coming up. But otherwise, you can use a rubber mallet, or even a hammer. You may have to do it longer to get good results.

Then add the reomesh. I needed slightly more than just the one sheet for the length, so I cut a bit off another sheet I already had. Then fill up with the remainder of the concrete. After that, vibrate again for as long as there's still bubbles coming up. I smoothed the surface a few times and vibrated again. I did probably 45 mins or so of vibrating.

Then that's it for the casting. Just smooth the surface as much as you want (it will be the bottom once you flip it, so it doesn't matter too much). Cover it with plastic so it dries slowly. It might need a light spray each day for a couple of days. Then put the plastic back on.

Remove the sides and flip it and remove the top. The sides and top came off super easy. Then I wet it down and used 240-grit wet and dry to sand it, then 400-grit for final wet sanding. After that I sealed it using penetrating sealer. I used a microfibre cloth and poured it onto the table and just rubbed it round as much as the table would take before it wasn't soaking in any more. I'm super happy with how it turned out. It's really strong and doesn't have any flex when you lift it from the two ends.

More inspiration for your table project

Workshop member kel19 created their own D.I.Y. dining table using plywood sheet and dressed Pine. 

 

Community member sammilne used three pavers to create this stylish travertine side table for just $66.

Check out our Top 10 most popular indoor furniture projects for more ideas. 

[teerodz]

@markw looks great!well done !what type of concrete did you use?sorry the link doesn’t work

[markw]

Thanks

 

 @teerodz, this is the concrete I used.

[Akanksha]

Hello @teerodz,

I agree - @markw has definitely done a terrific job with this tabletop. 

Are you looking to do something similar? Let us know if you need a hand with your project. We'd be happy to help.

Akanksha

[Random_will]

I'm really impressed it looks great. Did you use any additional additives or sealer?

[Dave-1]

Morning @markw 

How did I miss this project! Spectacular outcome, I have wanted to build myself a table top or benchtop for years and have come down to pretty much having it in my mind the way you described it. But you did it and have the pictures to show us how! It looks so professional its not funny,  

Really nice work and definently filing this away for future reference.

Dave

[Jason]

Thanks for joining in the discussion @Random_will. Let me tag @markw so he is alerted to your question about whether he used any additives. I note above Mark says he used a penetrating sealer - he might like to clarify exactly what he used.

Welcome to Bunnings Workshop. We're pleased to have you join the community and look forward to reading all about your projects and plans.

Jason

[markw]

Thanks @Dave-1 

@Random_will I used only the penetrating sealer, which is pretty good. It will be fine to protect the tabletop from most things as long as any spill is cleaned up right away. But if something acidic or oily for example is left on the surface for an extended period of time, it could leave a mark. An epoxy sealer could be the way to go to make it completely resistant to any stains, but I wanted to keep the natural look.

I have a clear vinyl tablecloth that I can put over it it's being used for a kids party etc.

[markw]

I can't figure out how to edit the original post to add any more pictures, but here's a picture of the table after I installed the legs.

I used these screws to secure the legs to the bottom of the table https://www.bunnings.com.au/ramset-10g-x-32mm-black-ankascrew-10-pack_p0261459

[Jason]

Thanks so much @markw. Great to get an updated photo. I have made it the hero image on this Featured Project article.

Jason

[billbum]

@markw 

Thanks this was really helpful. My slab tabletop is doing as i type this!

Couple of questions:

- how long did you keep it covered in plastic, and how often did you wet it while it's drying?

- which sealer did you use, and how much (do i need a 1 litre, 15 litre cab etc)?

Thanks!

[markw]

@billbum I kept it covered for a few days, and just checked it when I thought about it really. Probably a few times each day, and gave it a spray with a spray bottle.

1ltr would be plenty for the sealer.

Let me know how it turns out when you're done!

[JacobZ]

Hi @billbum,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

For a high gloss concrete sealer, Crommelin 1L Gloss Wet Look Concrete And Paving Sealer should be a good option.

You can also check out @markw's original post here - Concrete tabletop project. 

A number of questions have already been answered that might help you with finishing up.

Let me know if you have any further questions and please remember to share your project once finished. It would be fantastic to see what you come up with.

Jacob

[billbum]

@markw 

Thanks again.

One more question - which sander did you use or did you do it by hand? And which specific sandpaper (brand, type etc)?

I'm planning to pull the form off this weekend.

[EricL]

Hello @billbum 

It's fantastic to hear that markw's concrete top has inspired you to make your own. Let me tag @markw to make them aware of your question. It would be technically possible to use an electric sander, but it is critical that you keep the sander moving to prevent creating an uneven finish on the surface. Staying too long in a single spot could cause you to accidentally create a shallow dip on the surface.

Please remember to post an update, I'm sure our members will be keen to see how you made your concrete benchtop.

If you need further assistance, please let us know.

Eric

[markw]

@billbum I wet sanded it by hand, I think I started with 400 and went to 600 grit. I found that wet sanding gave a nicer finish than using an orbital sander to dry sand.

[billbum]

Here is my (almost) end result. The sealer is still drying so it's a bit splotchy. 

This is only a bbq work area, not a dining table so i cut a couple of corners which cost some aesthetics but very happy with the result. 

1. I didn't wait for the silicone in the form to dry, it grabbed the edges which are a bit rough. 

2. I set the form up on another, bigger, table so i couldn't access the bottom to vibrate, so there's a few tiny air bubbles. I filled the bigger ones in the centre with dune multi purpose filler so they don't catch food etc when I'm cooking.

3. I wasn't too worried about the finish but wet sanded it for 5 mins with a 320 grit sponge anyway and it is super smooth.

4. Used a natural finish rather than wet look sealer.

Vital statistics

1650 x 600 x 40

4 x 20kg bags

cost of materials and a couple of tools i didn't have approx $250

Thanks Markw!

 

 

 

[JacobZ]

Hi @billbum,

Nice work!

It looks like a fantastic workspace for when you're barbecuing up a storm.

Thank you for the update.

Jacob

[Dave-1]

Evening @billbum 

The bbq bench top looks great, nice work

Love the Bunnings buckets showcase as well

Dave