Mark, don’t measure miters
Test the fit, then fine-tune the miters
Start by cutting your moldings a little long so you’ll have material to trim off if the fit is bad. Then hold the miter joint together, making sure the trim pieces are held parallel to the door or window jambs, and check the fit. If you’re lucky, the miter will fit perfectly and you can trim a bit using the same miter saw setting. If the miters have gaps, like the ones in the photo, adjust the miter saw slightly and recut the miters. Then check the fit again. You may have to repeat this process several times.
Use a shim to cut a back bevel
Smash protruding drywall
Use a brad gun for the best results
Don’t nail too close to ends or edges
Pin the miter before nailing the outside
Shim behind the miter
Required Tools for this Project
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
- Air compressor
- Air hose
- Brad nail gun
- Combination square
- Glue
- Hammer
- Hearing protection
- Miter saw
- Safety glasses
- Tape measure
- Utility knife
Required Materials for this Project
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here’s a list.
- Brad nails
- Wood shims