Dropped undermount kitchen sink

[Havingago]

Hi. Undermount kitchen sink has dropped. Various advice on Google. Would something like Araldite epoxy be ok?

[MitchellMc]

Welcome to the Workshop community @Havingago. I'd be happy to help with your question.

Undermount kitchen sinks are adhered to the counter-top with silicone sealant. They might also have mounting hardware.

Araldite epoxy could have issues bonding to a polished stone benchtop and is rigid glue. I would recommend a polyurethane adhesive like Sika 300ml Black Sikaflex 11fc Plus Polyurethane Adhesive Sealant which has some flex to it and will bond well to those surfaces.

If you require further assistance with the process or had other questions, please let me know.

Mitchell

[Havingago]

Thanks very much Mitchell. I'll try that.

[koko]

Hi Mitchell. Same issue at my joint. Do you then also have to

 

 

seal the top with silicone or is the sika product all in one. Installer used pictured putty type product 5 years ago 

[StevieB]

Welcome to the Bunnings Workshop community @koko.

Let me tag @MitchellMc so he's alerted to your question. He'll be happy to help when he's back on the site on Friday.

Thanks for your patience in the meantime.

Stevie

[koko]

Cheers appreciate that StevieB

[MitchellMc]

Hi @koko, and welcome to the Bunnings Workshop community.

The Sikaflex 11fc is also a sealant, so there is no need to apply an additional silicone sealant.

In your circumstance, it looks like there is enough room to apply the sealant from within the bowl without removing it. Can you tell if any silicone has been used to stick the bowl to the underside of the bench, or was the putty the only thing holding it in place? If silicone has been used, you might need to remove the bowl to clean it from all surfaces. If no silicone is present, you'll need to clean the top lip of the sink and underside of the benchtop with a toothbrush. Once again, it looks like the sink has dropped enough for you to clean the mating surfaces in situ adequately.

You'll then be able to caulk a liberal bead of sealant around the full perimeter of the sink's lip and brace it up against the underside of the bench. You could use a piece of timber cut to the correct size to jamb under the sink. Dip your finger in soapy water and run it around the inside lip of the sink, forming a cove shape transition to the sealant. Allow a full 24hours for the sealant to cure before putting any weight in the bowl.

Please let me know if you need further assistance or have questions.

Mitchell