My sink attaches underneath, as opposed to having a lip which sits on top of counter. The sink detached, on its own - after 8 yrs. Originally they used brass inserts with a screw/wing nut/metal bracket to support the sink under counter - which is NOT Corian [I couldn't afford it then)], but is a slightly lower grade counter, which I see drills sort of like plastic.
I thought using larger inserts in the same holes would work but the insert's slot [for the screwdriver] breaks. Then I tested 2 inserts over night - put into enlarged, over-sized holes filled with Minwax Hi Perf 2-part wood filler. One insert failed. Original setup used 6 inserts. The sink is about 5 lbs.
Please comment on these ideas or offer better ones:
-Set it up with 4 inserts with filler which will stabilize the sink while I look and see if adding some wooden cleats can be done. I may be able to glue/screw wood -to-wood for the cleats.
-Set it up with 6-8 inserts with the filler and pray.
-Drill right thru the sink's lip and into pre-drilled holes in counter, using appropriate [which?] screws.
-As the sink had a layer of vinyl adhesive on its lip for water protection, I wonder if I could replace it with some kind of structural glue [which?]. This glue + 6 inserts might hold.
when i did my kitchen we got a sink that would undermount, flushmount or even mount sticking up above the counter. i made supports inside the cabinet for the sink to set on. maybe this would work for you. pictures would help. any chance of drilling new holes for inserts?