Baseboard gaps on outside corners

Old 09-08-21, 03:34 AM
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Baseboard gaps on outside corners

Iím in the process of completing a basement project to include hanging drywall, laying floors and installing doors.

im currently installing the baseboards. My mudding job was terrible at best most of it is square however I have a couple outside corners which are giving me up to 1/4 in gap on my baseboard. The gaps are about 3-8 inches long near the outside corner.

what should I do to take some of the gap out? It doesnít have to be perfect. My plan was to just use a razor blade to score the mud and chip mud out near the outside corner to bring the gap down a bit and just caulk the rest. Is this going to be an issue or a suitable fix?
Old 09-08-21, 03:53 AM
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The more you can do to square up the corner the better the base will fit. As a painter I've had to dress up many bad miters. You can do a lot with painter's putty. Sometimes caulking will stay put better but is harder to make the bad joint disappear.
Old 09-08-21, 04:48 AM
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I'm assuming you are talking about a gap along the top of the baseboard near the corner? If that is the case I would not "chip mud out" because all that would do is recess the base into the corner, making the reveal on top look weird. The best fix would be to just add more mud behind the baseboard to make the wall straighter. You don't need to do the whole wall, just enough to make the base look straight. A 10" knife would probably be perfect.

You could also put the base on straight then mask off the top edge to keep it clean and then apply your mud. The idea is to fool the eye and make the wall look just as straight as the base is.

If the gap on top is because of a bulge on the bottom part of the corner bead, then it likely needs more sanding or some scraping with a chisel. But the top edge of the base shouldn't really be recessed into the mud so much that it looks narrower. That would be just as bad as caulking a big gap and making the top edge look wider.
Old 09-08-21, 05:19 AM
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You can adjust the miter on baseboard for walls that are not meeting at 90 degrees. This does not fix gaps in the miter due to either or both walls not being vertical. One fix is to use a cheese grater/ bondo file. Grate the walls vertical back one stud (maybe 2) from the corner the height of the baseboard. Install miter. Another fix is to first nail the miter and fit each board of miter to length. Tape shims on wall to fill gap between baseboard and wall at the nailing points where needed. Mud wall the height of baseboard and thickness of shims plus. Nail baseboard at each shim until base board is tight against shim. Remove excess mud. Cut shim at top of base board when mud is dry.

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