Getting Started
As with any project, you have to do your research.
I needed to answer questions like: What do tombstones
look like? How are they shaped? What do they say on
them? How are people using them in their Halloween
displays? Most importantly: How do I make them on a
CNC router? So, I got a lot of great design ideas
examining epitaphs and tombstones using Google image
search. Unfortunately, most of the models I found required
3D contouring. With that type of work, I would first need
to spend the time creating a 3D model and even more
hours carving it out.
There are three primary phases to a CNC project:
1) Design: The drawing or CAD model.
2) Tooling: Creating the tool paths with CAM software.
3) Machining: Running the tool paths on the machine.
I am admittedly an impatient man. With time being a
finite resource we can never get back, isn’t everyone
looking for a faster way? So, let me show you how you
can use CNC routers to shortcut the 3D contouring
process. First and foremost, you want to create your basic
shapes and features using 2.5D operations. This is by far
the biggest time saver. I’m talking about pocketing,
profiling, and drilling mainly flat features on flat parts. You
then follow it up with a bit of hand sculpting. This
marriage between CNC and hand work produces
impressive results for this type of project, while shaving
valuable time from the process.
To start, I needed an inexpensive material that I could
get from my local home improvement store that was easy
to work with. The obvious choice was 2” thick foam
insulation which I purchased in a 4 x 8 foot sheet for
about $28. It’s thick enough to allow for a lot of depth
and contrast in my design, which really pops when hit by
a spot light on my lawn display. I happened to pick up a
panel of pink Owens Corning — the one with the Pink
Panther mascot (Figure 1). Other brands in other colors
should work equally well.
By Len Shelton and Melissa Shelton
September 2014 81
Save Time and Money
Making CNC
Halloween Decorations
Create complex 3D contoured parts
by combining fast and simple 2.5D
pocketing and profiling operations
with manual finishing techniques.
Post comments on this article and find
any associated files and/or downloads at
www.nutsvolts.com/index.php?/magazine/
article/september2014_Shelton.
When my friend, Vern asked me if I'd write an article for Nuts & Volts
demonstrating how to create a Halloween decoration tombstone on a CNC
router, I was psyched. I’m always looking for new and interesting ways to
show off all you can do with CNC machines. So, I agreed to give it a shot.
FIGURE 1.
Cutting my
2" foam
stock.