It is hard to believe that it was almost ten years ago I witnessed a CNC router in action for the very first time. I was fascinated and simply had to have one! Although I had been in the creative end of the three dimensional sign business for most of my life I didn't really know what I would do with one of these machines - but I just knew it could do fantastic stuff.

Along with the CNC router I discovered the wonderful material called Precision Board and the glues, primers and other companion products they offer. Since then we have gone through many tons of the material using it in most signs and projects we tackle. This journal will chronicle our many adventures both past, present and future. I'll talk from the perspective of someone who pushes these products to the creative limit on a daily basis. I'll be adding to the stories two or three times each week. -dan

Saturday, July 3, 2010

Creating a Precision Board panel with a plywood insert

I am traveling to Danville, Illinois in about a month to take part in a 'WALL DOG EVENT'. The old time sign painters who painted billboards and buildings with giant advertisements and murals were called wall dogs. The Mural painting event in Danville celebrates that tradition by gathering sign painters from all over and then painting 15 murals in only three days. One hundred and sixty-five artists are traveling from across Canada, The USA and beyond for this exciting event. I will be project leader for one of these murals. It will be the fifth time I have participated in such an event in this fashion. It will also be the 115th historical mural I have painted over the last 28 years. This is the mural I have designed for the occasion.
One of the events taking place that weekend is to erect a Sign Post Forest similar to the one in Watson Lake, Alaska. That world famous attraction was started by a lonely soldier from Danville - more than 70 years ago. We as wall dogs want to honor him by bringing signs to Danville, featuring our home towns and the milage to get back home. My sign simply has to be a dimensional one of course and I'll be using EnRoute to design it and my trusty MultiCam will be pressed into service. As always I'll be using 30 lb Precision Board to build it from. Because it will be screwed to telephone poles I will reinforce it with 3/4" plywood laminated inside. Although most folks will use miles to designate the distance to their home town I decided to use kilometers - just for fun.
I used the vectors from a new font I am working on to create the lettering. It's a cartoon design - very informal and fun. I'll combine this with the driftwood to create a weathered plank. I'll sculpt a cartoon bird on top to suggest the distance is 'as the bird flies'. I imported the vectors into EnRoute, then the driftwood bitmap which I traced. Then I selected the outline, and created a relief with a domed top (13 degrees). This rounded the top of the wood nicely. I added the driftwood texture bitmap using a value of 0.3".
Then I created an offset outline around the lettering and arrow of 0.2" I created a flat relief of this shape. Then I drew an oval around the relief and selected them both. The oval will be used to modify the relief in a dome shape using that same 13 degree angle. Once done I deleted the oval.
As you can see in the side view the lettering is now shaped with roughly the same profile as the wood grain panel.
I used the lettering vectors to then create chiseled lettering which were done at about a 21 degree angle. Before merging them to the wood grained panel I created a second copy of the panel and flipped it for the back. This side would have no lettering. To make room for the 3/4" plywood insert I used a copy of the vector outline. I used the outline tool to create an inside offset of about half an in thick. Then I drew a rectangle inside the panel leaving a generous border around the edge. I used the 'jigsaw weld tool' to create this new shape and then deleted the components I used to make it. I grouped the outline of the panel with this new shape and then used the toolpath tool to create the routing offset which would cut out a 3/4" panel with the hole in the middle for the plywood insert.
I then tool pathed the other panels and sent them to the MultiCam. They were routed in two passed - a rough cut using a 3/8" bull nose bit and a final pass with a 75% overlap using a 1/8" ball nose bit.
Once routed I removed the dust and then set about gluing them up using PB Bond -240, a Precision Board product. This glue is a one part adhesive activated with a little moisture. Gluing went quickly using a small bondo spreader to get an even coating. Once the three layers were coated and lined up I used plenty of small clamps to secure things nice and tight.
I'll be back soon to show how I worked up the edges of the sign to match the front and back... then a little sculpting and we are on to paint.