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Under-mount sink problems

Author: turbines (NC)

I have 1 inch marble vanity counter with a ceramic sink. The sink had to be mounted after the counter was installed due to space restrictions and a non-standard room size. After applying silicone the sink was positioned and the four furnished brackets and wing-bolts were installed. During this installation one of the threaded inserts in the bottom of the marble just fill out. When I examined it the material around the insert looks like epoxy but is soft enough to peal away with my fingernail. It's like epoxy that never cured and hardened. This causes me to suspect the other three inserts to be in similar shape with little or holding tension. Right now I have the sink wedged in place with boards until I find a permanent solution. I am thinking there might be a better support solution then trying to replace the four inserts. I have no experience with epoxy and marble. I would appreciate any ideas or suggestions.

Re: Under-mount sink problems
Author: hj The inserts and brackets may be the best way to support the sink, but the design of the cabinet and sink would determine that. WHO installed the sink and/or countertop? It is up to them to insert the anchors properly and secure the sink.

Re: Under-mount sink problems

Author: sozoal (CA)

Adhesive caulk might be a better choice than silicone, if the inserts are loose, have the supplier replace the unit, do not try to 'fix' these yourself.......yes I've been there before, and the 'puppy eyed' customer asked if we could just fix it instead of waiting weeks for a replacement and while gently re-inserting the inserts with epoxy, the @#**%$ marble cracked....because it is really weak at the insert points

Re: Under-mount sink problems
Author: turbines (NC) Counter came with inserts installed. Someone suggested a bead of PL Premium.

Re: Under-mount sink problems
Author: Shoemaker2 (MA) I would probably devise something out of finish plywood that could be secured to the inside of the vanity cabinet. I never liked those wimpy clips anyhow.

Re: Under-mount sink problems
Author: hj The countertop may have come with the inserts inserted, BUT somebody had to put them there so they would be in the right places. Granite does not come with them as part of the material.