miter before or after scribing?

[Ken Fitzgerald]

I have one last wall and corner to install baseboard to finish the kitchen trim. The floor on that side has a couple "wows" on it and the baseboard will require some scribing. The wall is about 4' longer than the baseboard material I could buy so I will need to miter the end and splice a piece on to get to an outside corner.

Then the baseboard needs to wrap around the corner for about 3'.

Where the baseboard needs splicing, should I miter both pieces before or after I scribe the bottom of the baseboard to fit the rolling in the floor? My thought is miter the ends before I scribe so I have 2 straight surfaces on bottom of the 2 pieces of the baseboard to use as a reference.

Or should I scribe & trim the bottoms and then bevel the joint?

Opinions based on experience appreciated!

[Kevin Jenness]

Miter first. Otherwise you risk tearout at the visible top edge. Install both pieces level and the joint should fit. Because you have to splice the long section, that gives you a chance to fine-tune the miter angle if necessary.

[Chris Kiely]

+1.

Mitre first. Use the same setting on the saw so it's bang on.

Trim later to suit if needed.

[Peter Quinn]

I'd scarf and glue the joint first, then scribe, then cut the outside miter. You could make the scarf the last thing you do the day before, let the glue set, treat it as one long board the next day.