The way I currently make frames has somewhat changed from when I first started. I used to make the frame around the piece as I was making it and would use multiple pieces to brace together the final piece. Now I usually make the frame and treat it with Tung oil all before the art piece is mounted. My process usually starts with 2x4’s or 2x6’s which are then cut into wide slats. I use a router to cut a groove out of one of the sides leaving a bottom lip and side wall. Those pieces are then cut at 45 degree angles into lengths for the frame. These pieces will then be glued and doweled together. I use clamps to hold them in place while drilling the hole for the dowel which is then hammered in with a mallet.
After the frames are assembled and sanded I use wood filler to fill any gaps or blemishes in the frame.
After the filler dries they are are ready to be sanded again and sealed with oil.
Sometimes I have a piece already made or at least the backing picked out which i’ll measure the dimensions of and make the frame for those specifications. I try to use as much of the wood as I can, so other times i’ll use whatever framing pieces I have around to create a random frame size and then will make pieces designed for that frame.
Treating the frames with Tung oil is a multi step process comprised of two steps repeated until the desired finish has cured. The two steps are sanding with a high grit sandpaper, and applying oil. To save space in the curing process I hang all the frames on long pieces of wood which can be slid into the bars of metal shelves and the weight of the frames keeps the wood in place. After each layer of oil has cured, the frame is sanded lightly, cleaned of dust, and then the oil is re applied with a rag. The number of times this is done depends largely on the type of wood used and desired finish. Most hard woods tend to not need as many coats to feel finished and the feeling I look for is a smooth matte surface which usually requires a minimum of 4 coats. The frame style I use is designed to be able to drop the piece down into the frame and use a combination of glue and dowels to fasten the backing to the frame. I then pour a two part clear resin on top to seal the top of piece and fill in the gaps between it and the frame.