I’m building a floating vanity countertop out of a large walnut slab. It’s about 6cm thick.
It’s wide and long enough that I can rip it on the front (facing the user) and on one end (the floating end, on the right) to give the top an apron.
I want to do that for esthetic purposes, so that it feels more like a tree and less like a shelf. And to hide the pipes under the sink a little. Therefore the mating edges will be mitered.
While I don’t need the aprons to support anything except themselves – the joints do need to deal with possible bowing/twisting of the top. The slab is completely dry (9%) but who knows what tensions will release once I cut it.
Originally I was thinking of a simple miter joint. Though “simple” is just a word when it comes to something this massive. And on the right (see drawing) it’s going to attach end-grain-to-end-grain, which given the weight and the fact that it’s floating will probably not hold.
So I thought – is it possible to combine the simple miter joint with a finger/box joint to get both the looks and the strength I want?
I made box joints very successfully using the method I learned on FineWoodworking (see Ed Pirnik video). But I don’t know if that will work if I have to hold one of the VERY heavy pieces at 45% while pushing a sled. In fact now that I wrote that – I think that’s unrealistic.
What do you think? Do you have any suggestions for a better solution?
Thanks in advance.