In making cove molding, you need to come up with a basic design that is pleasing to the eye. Something that is different, something that doesn't look store bought. For furniture you want to make it out of the same material as the body of the piece. In this section I will walk you through the process of making a period cove molding. Once you come up with a design put it on a piece of 3 mm plywood. Cut the plywood to shape and sand it. Examine it and see if it's what you have in mind. Hold it next to the piece to see if it will look good. I liked the design that I came up with and proceeded with it. Using the tools that are in the shop this is how I did it. In woodworking there are many ways to accomplish the task. Everyone may have a different approach, based on skills, tools available, etc. The end result will be the same with this path being surprisingly easy.
Use several test pieces (18' -24" long) in addition to the final piece. The size of the wood is 7/8" thick by 3 1/16" wide. You can't see it very well here, however, I did position and trace the plywood pattern onto the end of the wood. Here the cove was nibbled away to obtain the depth of the cove. Not being happy with the shape of the cove I tilted the blade slightly to open up the width of the cove. This gave it the appearance of a longer cove.
These are the router bits used to shape the molding. The bottom two are from Sears and not even going to tell you how old they are. You don't need the latest and greatest equipment to complete projects. Just take a few extra minutes and think how to use your equipment wisely.
First I ran the molding through in 3 passes adjusting the fence on each pass. This allowed me to put the straight lines in for the transitions. Look closely towards the top of the molding (farthest away from fence) the two straight lines will define the quarter round that will go in here. With the 1/2' quarter round installed and set to position, a pass is made on the bottom edge of the molding. This will define the majority of this. Later on we will come back and clean up the internal portions of the quarter rounds by hand.
On this piece you can see the layout and it starting to take shape. The chamfer bit is being used to make a square front on the top of the piece. Trust me! It will be square. The wood behind the two thick black lines will be removed in a while.
With the above setups completed this is what the molding will look like to this point. The two pencil marks are delineating the top and back edges of the molding.
Here is the chimney cabinet crown molding in progress. The piece on the left in the actual molding and the one on the right is the practice piece. What has been done to this point is: made the cove cut on the table saw and used the router table to cut the groves to define the quarter rounds. On the test piece I have rounded over the quarter rounds. A couple of different methods were tried and quickly settled on one to give me the greatest degree of accuracy. It is very important to maintain a uniform thickness all the way through. When it comes time to cut the miters and assemble it will be a lot easier.
The top of the molding was cut with a 37' angle with the back of the molding on the table saw top. The bottom of the molding was cut on a 37' angle as well. Lock closely at the top of the fence. For a piece like this I should have used a sacrificial fence that was at least 1-2 inches higher. It felt just a little tipsy at the top. Another important note: when doing work like this make sure to use a zero clearance insert.
The molding is square. This is the first real look at what it will be like.
Tommy Nielsen will probably be mad at me. I modified both ends of one of the scraper blades that came with this Lie-Nielsen scraper to fit my needs. Most likely I will live to regret doing that! But at the time it sounded like a good ideal. What I did here is us the smaller, modified end to scrape a quarter round into the top of the molding. Currently I'm using the larger modified end to scrape a larger quarter round into the bottom of the molding.
Using a good sharp card scraper clean up the large cove. Once done move onto the sand paper and finish it up.