My upstairs hallway is 23' long and one of its sides has no doors on it, meaning the baseboard on that side covers it continuously. I am using 1×6 poplar for baseboard and the longest piece my local lumber yard sells is 16'. I was thinking of joining two pieces but I don't want to have a visible transition.
The one idea that comes to mind is to biscuit join the two pieces or dowel them somehow. I also wonder if it would be better to just route a groove along the 6 side of each plank in the middle (so approximately 3/8" from each edge) and insert a joining strip of some sort that is elongated (i.e. looks like a popsicle stick). Once the joining and gluing is done, sand it really well.
Does one of these approaches sound right or is there a better way? I am sure there must be a way to fabricate really long baseboards from smaller pieces with a seamless transition.
Best Answer
The standard practice is a 30 degree scarf joint preferably joined on a stud. I like to miter my two end with the same setting so I know the angle is perfect(when possible) then take my pieces to their wall a little over sized and scribe them to the floor (making sure the top line of the trim is on plane) and mark out for your end cuts. Once fit, position your pieces and join them with glue and micro pins(skip this if you don't have a micro pinner, brads just make a mess). Let it tack up for a minute and the start securing it with finishing nails. Try to crisscross nails at the scarf without getting too close to the joint. Cheers!