I just finished a project using flexible molding and thought I would give a report on my impressions. The molding is flexible polyurethane trim I purchased online from Flexible Moulding Concepts
. I used flat stock but it is available in many profiles. I purchased it in eight foot (243.8 cm) lengths although it is available in lengths up to 20 feet (609.6 cm).
The project was trim for a curved opening between two rooms. The first two photos show the before and after. Since the trim is painted I used half inch (12.7mm) MDF for the casing with 3/4" (19mm) thick molding for the casing cap and 1/4" (6.4mm) thick molding for the fillet along the bottom. The top cap is 1 1/4" (31.8mm) wide and the bottom fillet 7/8" (22.2mm) wide. Both were glued to the edge of the 1/2" MDF with Loctite polyurethane construction adhesive. Since I was attaching to the edge of MDF is could not use nails or brads. Install would have been much easier if I could.
The thick top trim was pretty stiff to work with but once I got a few key clamps on it was manageable and bent well to the shape of the casing [photos 3 and 4] . On the other hand, the bottom trim is like working with a wet noodle. [See photo 5] I had a difficult time clamping it. After running out of clamps, I finally resorted to holding it in place with masking tape every few inches until the glue dried over night.
It was shipped coiled in flat boxes [Photos 6 and 7]. The polyurethane wants to hold that coil shape. I dry clamped it place for 24 hours but when I took off the clamps it immediately wanted to return to its original shape. Not a big issue, but in my application the cap hangs over the casing by 3/4" on the ends and the original coil gives it a slight curve even in that short distance.
The material cuts and machines easily but since it doesn't lay flat I don't see how it could be machined on a router table. For painting I used Glidden's primer and sealer as a base coat because it will stick to most anything. Top coat was with a water-based interior enamel. The manufacturers say the material can be stained. I haven't tried it but I suspect we are talking about using a polyurethane gel stain of some type.
Final score: 7 out of 10 for my needs.
Pros: Flexible, easy to machine
Cons: Awkward to work with, wants to retain shipping shape, needs polyurethane glue
Would I use it again? Yes but only for special cases like this project.