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5 replies
12k views
5 replies
Casting sink countertop in concrete
Hello.
I have now read everything available on the subject of casting your own concrete countertop, and I feel confident to dive into it.
But there's one question I haven't been able to get an answer to.
If I want a sink, can I place the sink at the bottom of the mold, make sure it's really pressed against the bottom, and then pour in the concrete.
Shouldn't the sink be flush-mounted then?
Is there anything negative about this? Apart from the fact that the sink is hardly replaceable.
Grateful for answers
I have now read everything available on the subject of casting your own concrete countertop, and I feel confident to dive into it.
But there's one question I haven't been able to get an answer to.
If I want a sink, can I place the sink at the bottom of the mold, make sure it's really pressed against the bottom, and then pour in the concrete.
Shouldn't the sink be flush-mounted then?
Is there anything negative about this? Apart from the fact that the sink is hardly replaceable.
Grateful for answers
Hello,
When I made a concrete countertop with a sink, I created a model of the sink in formply and Styrofoam so that when I removed it after casting, I could lower the sink into the countertop to the thickness of the formply and attach it with the appropriate mounting. I don't think the casting would be a problem if you cast the sink in place, but keep in mind that you would probably want to sand the surface a bit, and it might be difficult to avoid sanding the sink, making it less visually appealing.
However, my solution did not allow the sink to fit perfectly, so I chose to silicone around the sink, which didn't look very nice after a while. The easiest solution is probably to ensure that you cast a hole in the countertop corresponding to what you would cut out of a wooden countertop (a piece of Styrofoam glued in place or similar) and install the sink "on top" of the countertop. I don't like this solution as it becomes troublesome to wipe down and sweep debris into the sink since there is a small ridge.
/Ola E.
When I made a concrete countertop with a sink, I created a model of the sink in formply and Styrofoam so that when I removed it after casting, I could lower the sink into the countertop to the thickness of the formply and attach it with the appropriate mounting. I don't think the casting would be a problem if you cast the sink in place, but keep in mind that you would probably want to sand the surface a bit, and it might be difficult to avoid sanding the sink, making it less visually appealing.
However, my solution did not allow the sink to fit perfectly, so I chose to silicone around the sink, which didn't look very nice after a while. The easiest solution is probably to ensure that you cast a hole in the countertop corresponding to what you would cut out of a wooden countertop (a piece of Styrofoam glued in place or similar) and install the sink "on top" of the countertop. I don't like this solution as it becomes troublesome to wipe down and sweep debris into the sink since there is a small ridge.
/Ola E.
If you have a really cheap ho, like a 3-400 kroner one from Ikea, maybe you can plastic/oil it so that you can remove it when the concrete has set. Then you can sand without risking ruining it. If it can't be removed without extreme force (so it breaks), you've "only" thrown a few hundred in the lake...
I've never tried it, but I've personally thought of doing as described when I build an outdoor kitchen!
I've never tried it, but I've personally thought of doing as described when I build an outdoor kitchen!
Thank you for your answers. I understand the issue of potentially damaging the hon during sanding.
I was thinking maybe I could put duct tape on the inside of the hon and possibly remove the hon before sanding.
I will go with an IKEA sink as @ejeras describes so it's 3000 at worst that I sacrifice.
But to avoid damage when sanding, I should be able to wrap the hon thoroughly before sanding and be careful so that there are no damages.
@ola.eriksson how long did it take you to sand the countertop? Did you use a machine or do it by hand?
I was thinking maybe I could put duct tape on the inside of the hon and possibly remove the hon before sanding.
I will go with an IKEA sink as @ejeras describes so it's 3000 at worst that I sacrifice.
But to avoid damage when sanding, I should be able to wrap the hon thoroughly before sanding and be careful so that there are no damages.
@ola.eriksson how long did it take you to sand the countertop? Did you use a machine or do it by hand?
I tried to rent a diamond grinder like an angle grinder but it didn't work at all, way too coarse a tool so I ended up hand sanding with wet sandpaper. I've seen there are machines where you can also add water but couldn't find one to rent. Maybe there's one in your area. Regardless of how you do it, make sure to get as smooth a surface as possible from the start (after casting) because it's not fun to sand concrete.P PBPB said:Thank you for your answers. I understand the problem of possibly damaging the sink when sanding.
I thought maybe I could put duct tape on the inside of the sink and possibly remove the sink before sanding.
I'm going to go with an IKEA sink so as @ejeras describes, it’s 3000 I'm sacrificing in the worst-case scenario.
But to avoid damage while sanding, I should be able to wrap the sink properly before sanding and be careful not to cause any damage.
@ola.eriksson how long did it take you to sand the countertop? Did you use a machine or by hand?
Hello!
I am facing the same challenge. I have cast a countertop once before and used foam for the sink. It worked well, but as someone previously mentioned, it was difficult to fasten the sink with Ikea screws, so I had to supplement with silicone. It turned out fine, but maybe not optimal.
This time, I'm considering if it would work to cast with the sink in the mold. Therefore, I'm wondering how it went for you or others who have tried.
Did it turn out well?
Was it possible to remove the sink during sanding? Did you use oil to remove the sink?
How did you secure the sink in the mold to ensure it was really tight?
Anything else to consider?
Looking forward to a reply in a very old thread.
I am facing the same challenge. I have cast a countertop once before and used foam for the sink. It worked well, but as someone previously mentioned, it was difficult to fasten the sink with Ikea screws, so I had to supplement with silicone. It turned out fine, but maybe not optimal.
This time, I'm considering if it would work to cast with the sink in the mold. Therefore, I'm wondering how it went for you or others who have tried.
Did it turn out well?
Was it possible to remove the sink during sanding? Did you use oil to remove the sink?
How did you secure the sink in the mold to ensure it was really tight?
Anything else to consider?
Looking forward to a reply in a very old thread.
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