Here's a little update showing how to take this approach one step further to make a nice little trim ring for your routed opening. The great thing about a router template is the way it eliminates all guesswork about fitting or reproducing a certain shape. Once you have put the time into the template you can make as many holes or parts as you need.
In this series of pics I am modding the side panel a of a Silverstone Sugo for a client. I'm enlarging the opening and making a two part bezel or trim ring of aluminum and UV reactive acrylic. The Aluminum Bezel fits over the Acrylic Bezel so only the edge shows and glows and functions to hold down a piece of powdercoated hex mesh over the opening.
Starting off by taking a piece of 3/4" Melamine and lining up the side panel where I can mark the cutout. The Melamine will be my router template for the side panel, aluminum and acrylic bezel pieces.
Once I have the side panel where I want it I mark the inside of the window as well as the outside of the panel to facilitate alignment later.
The new opening is just taller and uses the existing sides of the opening. But it needs to be perfectly symmetrical and fall exactly on the panel.
Using a trisquare I find where the tablesaw blade will cut when jacked all the way up. This is prep for a drop cut to start the template.
Tablesaw drop cuts completed I can now finish it with the jump up and down saw.
Rough cut completed and now it's time to block sand it true.
Perpendicular and straight and flat. Ready to use as a router template.
Realigning the sidepanel to mark the waste material I will cut out with the Fein Multimaster.
Waste material remived. I only want to route 1/8" of waste from the panel for safety and for the best results.
Stuck to the template with DS tape.
Routed.
Pattern for routing the outside of the trim ring or bezel that secures the mesh over the opening.
Bezel blank routed and removed from template and now I am removing the waste material from the center using a step bit in my cordless drill and the Fein Multimaster.
Bezel fixed to the template ready to route.
Completed bezel. Ready for powdercoat just about.
Matches opening in side panel exactly.
Cut a piece of powdercoated mesh.
Just about a finished product.
Only piece left to make is the UV Reactive Blue acrylic bezel that fits under the aluminum bezel. I'd like to figure out how to hide the screws under that aluminum bezel...I think that would look really trick. The edge will flouresce naturally and any UV light source will make it really glow.