I was able to purchase a 3/4 inch thick solid PVC board today from a local supplier. The board was 18 feet long and 7.25 inches wide. It should yield 24 ADA door signs making the price of each sign blank about $1.87 each.
I cut a small piece off of the end of the board and routed a test sign blank on my CNC Router. The PVC routed beautifully, cuts like butter and it sands real quick with an ROS. PVC is very light compared to Corian, it machines just like wood.
I painted my test piece and will do a little more testing tomorrow to see how well the paint adheres. So far I am very impressed with PVC as a less expensive alternative material to Corian for certain types of signs. PVC is available from my local lumber yard in various board sizes and in sheets up to 120 inches by 48" and thicknesses from 3/8" to 1". My memory isn't reliable but I believe the price quote I received for 3/8" thick sheet 48" by 96" was $69.00. Purchasing full sheets should bring the price per sign blank down even more.
Laser Engraving isn't an option but it can be routed on a CNC router or on a rotary engraver at very high speeds, thus reducing the fabrication time considerably. I will be glad to share pictures and my final data when the first couple of sign blanks are complete if anyone is interested.
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