First I squared two sides of the chunk, then I drilled two 13 mm holes for the half-round grooves. Then I ripped it lengthwise.
Like so. I cut it to length but kept it a couple of mm long, the reasoning being it’s better to have a slightly larger footprint to cover any boo-boos from removing the old one.
I tried to use a chisel to shape the three-sided pyramids but I could just as well have used the chisel on a piece of glass. So I roughed them out on the belt sander. I know! Show me a builder who’s made more derogatory remarks about abrasives than me and I’ll be impressed.
Then to make amends I switched to a French handcut rasp, crazily expensive but for this, invaluable.
And here’s where we’re at. I won’t go further without the old bridge beside me, but the heavy work is done and with the luxury rasp, a sharp file and some scrapers I can continue in the apartment.
