Hello Lemmy,
Youve been so helpful over the last few months. Maybe someone can help me with this.
I have this butchers block countertop with an undermount sink. I had it installed 18 months ago. I sealed it, and then this part was being warped and forced apart. I put in wood block, I resealed it. But as you can see, its coming apart again.
I followed all the advice of the handy men I know, including the one that installed it. The only thing I can think of is, aside from reblocking and sealing it, maybe a line of silicon around where the faucet comes up, and around the lip where the sink is flush with hole its mounted in, both things they assured me wouldn't be necessary. Should I be concerned about a leak on the underside? Am I just hosed?
(More pics of the whole set up on request)
If bowing of the entire counter is forcing the center apart, -maybe- you could stop it (or possibly correct it somewhat) by screwing in strips of some non-warping material (wood maybe, metal might be better, like beefy aluminum angle) at intervals underneath the counter. Orient them perpendicular to the direction of the butcher block strips. Put screws in every few inches.
It was fear of this warpage happening that when I redid our kitchen with butcher block counters, I chose a drop-in/overmount apron front stainless sink. Has like a 3” wide lip all around on top of the counter, and is thin enough (roughly 1/16”) that once I put a bead of silicon at the edge, I can still easily rake crap off the counter right into the sink. Faucet, etc is all mounted on the sink, so less water exposure. About the worse thing so far has been some surface crud on the wood between the back lip and the wall.
I may be a little too deep to replace the sink. I guess drop ins aren't that expensive.
Do you have any suggestions for angles?
Maybe something like: https://www.homedepot.com/p/Everbilt-1-1-4-in-x-5-ft-18-Gauge-Thick-Zinc-Plated-Slotted-Steel-Angle-15152/332733420
Not aluminum, but galvanized steel, so should be ok in moderately wet environment. Plus, it’s cheaper than the 1/8” aluminum angle at HD. You could prob get 2 strips from each, or they may even have longer lengths for cheaper.
You’d just have to make sure you’ve got 1.25” clearance (e.g. don’t screw it in right above a drawer).
Of course, one of the things with butcher block is that it’s gonna expand and contract with humidity, so you can’t completely restrict it. But I think that if you use screws that have diameters that are smaller than the pre-drilled holes on that angle, even when they’re screwed in tightly, they’ll have adequate lateral movement.
Disclaimer - I’m not a “carpenter” by any means, but I do nearly all of my own home repairs, and the above is what I’d prob try if faced with your problem.