Body No Fly

&

Template Fit

We need to ensure that no hardware (e.g., bolts, washers, alignment pins, clamps, etc.) encroach into the path of the cutter. We therefore need to designate a "no fly" zone to define the outer limits of the body cutout toolpath. Once we have the no fly zone, then we need to determine how to adjust the layout template in relation to the body and origin to specify how much, if any, Y-axis shift is required from the body tooling tooling origin.

The No Fly zone will be a space offset from the outermost (roughing) centerline cutter pass.

Display the guitar body's layer and the finish and rough passes as shown above.

Unlock the guitar body as necessary and use the Modify -> Offset command to create a 0.560" offset.

Why a 0.560" offset distance?

0.250" - Body to finish pass (i.e., the radius or R)
0.030" - Finish to Rough offset (nominally 6% of DIA)
0.250" - Rough centerline to outside of cutter (R)
0.030" - Additional clearance (~1/32") for "slop"

Rule of thumb: use the same offset of the body edge to rough pass as the rough pass to No Fly.

Note that the curl in points begin outside the No Fly zone so we need to now modify the no Fly zone to include the curl on.

Draw a circle with the center on the plunge in point and a radius equal to the rough pass to no fly distance (in this case, 0.280").

We need to then offset the outermost curl on pass.

Create a circle on that pass (typically the finish pass).

Next offset that "curl on" circle by the same distance as the radius of the circle at the plunge in point (0.280").

This new circle should be tangent at that plunge in point.

To reduce the clutter, delete the circle on the curl in arc and turn off the centerline tool paths .

Select the three objects:

No Fly edge polyline;

Plunge in circle; and

Curl on circle

Use the Modify -> Trim command and delete the unnecessary geometry.

You are typically left with an ear-shaped bulge on the No Fly edge.

We now need to create a layer for the No Fly edge.

"EDT-Body-NoFly"

with a color of a light blue will do nicely.

Select the Body No Fly edge and

Push the object to the EDT-Body-NoFly layer

Now is the time to have a look at how our body will fit onto the Guitar tooling on the CNC router. Let's display the three (3) Template layers

Make the following CPZ (i.e. Laser) layers visible and unlocked:

CPZ_Template_Rename-Raster_Etch
CPZ_Template_Rename-Vector_Cut
CPZ_Template_Rename-Vector_Etch

Zoom -> Extents to see the Body & Body-No Fly edges and the Template

Select the Body NoFly edge polyline and copy it from 0,0 to 40,0

Now zoom in on the template and let's see where the outer limits of the guitar cutter paths sit in relation to the mounting hardwear

GREAT! IT BASICALLY FITS.

(If it didn't, we might need to rescale the guitar a bit...

in other words, head back to the Refining the

Body Shape step)

As it is, we can see two obvious problem spots:

(Upper left corner) The no fly edge of the upper horn interferes with the large washer; and
(middle left) There is a wee bit of interference with the no fly edge and the middle left large washer.

Note: As the no fly width is oversized by 0.030", #2 is probably OK as is. Also, we could specify a "Small" washer. But we'd rather not do either.

By inspection, the appropriate template data needs to be shifted up a bit—say, from 3/4" to 1"—for the Body NoFly edge shape to fit comfortably from the mounting and alignment hardware.

Select pretty much all of the template data

That is everything except the middle bits (such a s the neck, the two humbucker center holes and note and the bridge ground and not)... that data stays with the guitar body (i.e., doesn't move...yet).

(If you do select and move the middle bits, no problem.

We can fix it later)

Use the Modify -> Move command to shift the template data in the positive Y direction enough to clear any/all interference.

In this example, we moved (relative) 0,0.75

Δ X = 0"

Δ Y = 0.75"

Let's update the "SHIFT" value

Select the "Y±9.999", right click and choose "Edit" then change to the correct value which, in this case, would be "Y-0.750"

NOTE: use the negative of the value the template data was shifted in the Y direction.

Once the template data has been shifted, delete the Body-NoFly (light blue) edge object... we'll bring it back later with all of the appropriate guitar data.

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