I should have done a WIP !
When I started I really had no idea how it was going to end up or look. So the timber started out much thicker than the end product. I got the width exact and slid it along the wooden floor until it butted up against the tiles. Then it came back out again as I realised there was a lot of grout and bits of cement in the way! Cleaned all that up then slid the wood back and ran a pencil line along the wood using the tile surface as the reference.
That gave me a line for a sloping rebate to follow the tiles. How to cut it ? I'm fortunate that I have a very nice sliding table on my combi. I made a couple of marks on the wood about 3" in from each end and stuck don on the sliding table a couple of pieces of masking tape that coincided with those marks. I moved the timber to one end and aligned that end of my cutline with the table saw blade (riving knife removed...!
) then marked up a reference line on the masking tape so that I could put the timber back in the right place again....hope this is making sense.. I then moved the sliding table along and got the other end of the cutline aligned to the table saw blade and marked that position on the masking tape.
So now, even if I moved the timber on the sliding table I could re-position it in the right place against those two marks. Removing the riving knife wasn't a problem as I have a clamp on the sliding table (sneaky, huh?) thus keeping fingers clear. Adjusted the height of the blade to give the depth of overlap for the timber over the top of the tiles. Made the cut.
Now I have to make another sloping vertical cut to complete the rebate. This time I dropped the blade to the lowest level I needed and ran the timber over it. Then raised it a little, repositioned the timber so that the next cut would start a bit further down the rebate where I needed that deeper cut. And so on until the last pass finished the rebate.
Offered up the timber and realised the rebate needed a little finessing. Again I'm fortunate to have a couple of skew planes which made short work of that. Offered it up again, then I took a step back and looked at it from both sides. Realised it was too high over the tiles and so ran another pencil line about 1/8" above the tile top. Bandsawed that excess off the timber.
Then went to look at the timber from the bedoom side and saw that it looked wrong because of that slope on the bedroom floor.. So ran another pencil line along that vertical and that now gave me something to aim for. Back in the workshop, planed and sanded until it looked right. Because I needed a twist on that top surface (has to be).
Hope that helps...shout if anything's not clear.
If opportunity doesn't knock, build a door.