Altar Build: The Double Arches

 

With my template that I cut out earlier laid onto my newly cut to width front panel, I could trace out the double ogee arch decoration that will go there. I drilled some holes on the insides of those lines and carefully cut the middle parts of each are out, leaving about a quarter inch of material between my cut and the line. The reason for that is because I was using a jigsaw to cut out the middle parts and it leaves a very rough cut, the blade doesn't always track straight up and down and it tends to splinter the edges of the wood being cut which isn't very attractive. I have a secret weapon for fixing all those defaults but it only works if the majority of the waste wood is removed first.

This is how the double arched panel looks after I cut it out with the jigsaw. You can see the lines I drew still there and the wavy edges left by the jigsaw.

Above is a closeup of the front panel with some double sided carpet tape adhered in a few spots. I will put my template on top of the tape, aligning all my markings up and stick the two pieces together. This allows me to use my secret weapon tool.

Above is the business end of my secret weapon tool. Essentially, it is a router that I built into one end of my table saw table. In it is what is called a compression cut bit. In essence, it cuts in both directions toward the center of the bit. The double helical cutting surfaces that do this are not easy to see if you don't know what you are looking for but it works quite well. If it has a single helical cutting head as most of my router bits have, it tends to blow (woodworking lingo for splintering) wood out the backside of the cut which mars up the surface of your project. This bit ensures all the worst forces are centered on the thickness of your board where surrounding wood fibers can provide the most support. The bearing on top of the bit it adjusted in height to ride around on my template guiding the cutting portion of the bit.

The end result is that the bottom piece, the piece going into the altar, is cut exactly on lines in a perfectly straight or curved line that follows the template exactly. Using this method and the same template, I could make exact duplicates of the arch hundreds if not thousands of times. In my case, I only needed to do it once more. The one drawback is that the guide bearing doesn't fit into corners very well so I have to clean up the corners by hand using a sharp chisel to square them up.

Once that was completed, my front panel is now done for now. Eventually, I will cut thin strips of wood with a decorative bead on the edge to apply to the inside edges of each are to cover up the exposed plywood core veneers that make plywood ... well plywood. It will also dress things up a bit.

Finally, I aligned the six different individual panels that will make up the front panel assembly of the carcass. I needed to layers in order to have something on the backside of the arch openings. Someday, the church might buy some decorative symbols or ornamentation of some kind to mount inside the double arches. I am going to use epoxy to bond the panel surfaces together since it has a long open time (measured in hours and not minutes like wood glue) which will give me a lot of time to get the panels situated exactly where they need to be and clamped together. To clamp them together, I will be using dozens of screws from the backside to hold things together. Epoxy gives me time to do all of this before it starts to set. Unfortunately for me, I need around 12 hours of above 55 F weather in order to bond all those panels together and allow the epoxy to cure properly. The 10 day forecast for here has the high predicted to only be in the middle 50's each day for the next ten and the lows in the upper 30's. The one exception is tomorrow which has a high of 70 degrees forecasted and unclear if it will remain that way for a full 12 hours. More than likely, I'm not going to chance it and will just delay the build for a week until more reliable warmer temperatures are here to stay.

One thing to note. The seams on the front face of the panel assembly, on either side of the double arches, will be covered up by the fake columns that I will build once the carcass is together. I had to put seams in because I can't get plywood in the width required and still have the grain direction running vertically as seen above.