How to Curve Moldings

Molding is found around doors, windows and many other areas of the house. It is made out of many different materials, including wood, vinyl and composite. Some houses have an archway that will require molding to be bent. Molding can also be bent to form shapes around the exterior of your home. Archways are shaped in a half circle and the molding can go around the outside of the archway. Vinyl and composite molding can be bent easily by heating them up, but bending wood molding involves a little more time and detail.

Things You'll Need

• Tape measure
• Pencil
• Reciprocating saw
• Clean rag
• Wood glue
• Heat gun
• Gloves
• Safety goggles

Instructions

Bending Wood Molding

1. Measure the length of the curve where you will be installing the molding. Record the measurement. Transfer that measurement onto the piece of molding you will be bending.

2. Lay the molding down on a flat surface with the bottom facing up. Make a small line with a pencil every inch along the width of the molding where the bend will take place. These marks are where the kerf lines will be cut. Kerf lines are small grooves cut into the back of the molding in a straight line.

3. Cut kerf lines into the molding with a reciprocating saw. Line up the blade of the reciprocating saw with the first mark on the molding and cut slightly into it with the saw. Hold the saw with both hands and cut about half the thickness of the molding. Follow carefully along the pencil mark lines and repeat the process along the entire width of the molding.

4. Move up to the next mark and repeat the process. Continue until all of the cuts have been made with the reciprocating saw. Using a clean rag, wipe any sawdust and debris from the area where the "V" cuts were made.

5. Squirt wood glue into the grooves where the cuts were made. Let the glue dry overnight so it does not drip out when you are bending the molding. This will also allow the molding to strengthen and not break when it is being bent. Bend the molding over the area where you are installing it until the proper curve has been achieved. Repeat the process for any other pieces that need to be bent.

Bending Vinyl and Composite Molding

1. Measure the area where you are going to bend the trim with a tape measure and record the measurement. Lay out on a table a piece of molding that is long enough to cover the area where you will be doing the installation.

2. Plug in a heat gun and turn it on. Position the heat gun so it is 4 inches from the molding. Move the heat gun back and forth over the molding, beginning at one end and working toward the other. Do not hold the heat gun in one place for too long or it might melt the molding.

3. Shape the trim by hand. Bend it to the desired angle based on the measurement of the archway. Continue heating it up from one end to the other with the heat gun and bending it by hand until the shape you want is achieved.

4. Let the trim cool down for at least one hour before attempting to install it. Repeat the process for any other pieces of trim that you want to bend with a heat gun.

Tips & Warnings

• Safety goggles are recommended when you are using a heat gun.

• Wear gloves when you shape the trim after heating.

References

• OnlineTips.org: How to Bend Wood Molding
• Wood Web: Heating and Bending PVC Trim