I'm working on figuring out how to get my sink mounted before I put my countertops in place. I have an undermount sink, so I'll cut a hole in the plywood that I'm going to run under the countertop for support. The top of the sink will be on top of the plywood, so I have to figure out how to make it flush, else the piece of countertop around the sink will stick up by that much. So, any suggestions on what (and how) to do to make the area where the sink will rest on the plywood recessed enough so this won't be a problem?
undermount sink on plywood base
- Thread starter b_m_hart
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jonny round boy
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Easy!
Make the cut-out in the plywood;
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Drop the sink into place;
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Draw around the rim with a pencil, and remove the sink;
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Use a router to remove the excess material to the required depth (it won't be seen at all, so you can do this bit freehand);
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Then when you put the sink back in, the top edge of the sink will be flush with (or better still, slightly below) the face of the plywood;
[attachthumb=5]
Make the cut-out in the plywood;
[attachthumb=1]
Drop the sink into place;
[attachthumb=2]
Draw around the rim with a pencil, and remove the sink;
[attachthumb=3]
Use a router to remove the excess material to the required depth (it won't be seen at all, so you can do this bit freehand);
[attachthumb=4]
Then when you put the sink back in, the top edge of the sink will be flush with (or better still, slightly below) the face of the plywood;
[attachthumb=5]
dirtydeeds
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without being too obvious
whatever method you eventually plump for, even with good quality hardwood wbp / marine ply seal the edges against water / germs.
use a sanitary sealant with microban (if avaliable) NOT cheap builders mastic
im aware that wbp and marine ply are british quality standards that you will not recognise
the inference being, buy the best quality american ply avaliable
whatever method you eventually plump for, even with good quality hardwood wbp / marine ply seal the edges against water / germs.
use a sanitary sealant with microban (if avaliable) NOT cheap builders mastic
im aware that wbp and marine ply are british quality standards that you will not recognise
the inference being, buy the best quality american ply avaliable
You could also pour the counter with a spacer in the form, so that when installed, it leaves a void in the area of the sink edge. You could also set undermount bolts in the top when you pour it. I could think of at least two other ways to skin the cat, Jonny's would be right up there though. I'd agree with DD as well, and additionally offer that you use silicon on the top face of the sink before you mount the countertop.
jonny round boy
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Sorry, I should have explained this a bit better - you need the sink itself to be slightly (1-2mm) below, in order to have room for the silicone to form an effective seal. If it's flush, then pretty much all the silicone will be squezed out & there'll be too little in there to seal it properly.
Roland Chung
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- Mar 12, 2007
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JohnnyRoundBoy offers an excellent illustration. All I can add is a couple of variations.
Depending on the type of adhesive under the ctop or the condition of the ctop, there can sometimes be a larger gap between the bottom of the ctop and the substrate than anticipated. With JRB's method, you could put shims in from below to help snug up the sink to the ctop. Some installers run screws through the underside of the lip to push the sink up into the ctop.
Another variation is to cut the opening completely through the substrate and then attach blocks at several points below the substrate. You would shim or run screw to snug the sink up. The advantage of this method allows for an easier replacement should the need ever arise.
Roland
Depending on the type of adhesive under the ctop or the condition of the ctop, there can sometimes be a larger gap between the bottom of the ctop and the substrate than anticipated. With JRB's method, you could put shims in from below to help snug up the sink to the ctop. Some installers run screws through the underside of the lip to push the sink up into the ctop.
Another variation is to cut the opening completely through the substrate and then attach blocks at several points below the substrate. You would shim or run screw to snug the sink up. The advantage of this method allows for an easier replacement should the need ever arise.
Roland
