The shape of the frame moulding is called its profile. These are a couple of dozen basic profiles and thousands of variations. There are also many ways to finish a moulding, and we cover that in the next post. Here we will talk about cutting and joining a pre finished length of moulding typically purchased 8 to 10 feet in length. When a frame is constructed by first joining an unfinished raw wood profile and then finishing it as a single unit, this is called a "closed cornered frame". We will cover also this in the next post.
When constructing a frame, the frame moulding has to be cut, and mitered (corners cut at a 45 degree angle) and then they have to be joined. Cutting can be accomplished by a hand saw, electric saw, or foot chopper. A chopper is a mechanical device where a sharp blade falls down on the moulding and slices through it at the proper angle. Each of these methods has its advantages and its drawbacks. Cut moulding pieces have to be evaluated for the proper cut angles and "dressed" to ensure that a good joined corner will occur.
Once the moulding has been cut to the proper length and width with the correct allowance (see previous post) it has to be joined at each corner. This is accomplished by gluing, thumb nailing (a plastic wedge driven into both sides from behind), brading (thin wire nails), and/or v-nailing (a v-shaped staple fem the back) the corners together. We use a combination of these methods here at our shop. We may glue the corners together held together in special vise, and then either brad or thumbnail in addition for added strength. Gluing and v-nailing can also produce a strong corner. Brads or thumbnails without glue are not sufficient. The shape of the moulding and the desired appearance and strength will help determine which method is used.
Prior to gluing we may touch up the raw ends with color to match the frame finish. Once joined the frame then is inspected for any minor flaws and either touched up or color matched putty is used where needed, particularly if there are brad holes.
Lastly we test fit the frame with the art to ensure size and dimensions are as intended, and set it aside while we build out the rest of the package which can include mats, glass, backing and other special materials as designed.