I just put in MDF baseboards and have patched the nail holes. My question is on the outside corners I did not make accurate 45 cuts. There is a small gap which I thought I could fill in with a painters caulk. Where the 2 pieces come together one side is about a 1/16 to long. Should I caulk the gap and then sand them down or should I sand them down and then caulk? The baseboards were not painted. I need to caulk , touch up primer, and then paint. Anything else I should know and what order I should do them? Should I use Dap painters caulk with or without the silicone?
I would sand down that 1/16th inch, then caulk. I use a paintable caulk that has silicone, 35 year. Don't use pure silicone caulk, it's not paint-able.
I generally paint the baseboards before I put them down, then touch up after. And having problems with the corners is nothing new or unusual. It's all part of the 'fun' of construction.
For wood joints and nail holes I use Elmers wood putty.
Where the trim or molding meets the wall etc., I use caulk.
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