Laser Cut Pepakura
If your design’s polygon density has not been sized appropriately for an unfold the result
may be too many facets to glue together. Use the freeware, Meshmixer, available at
autodesk.com. to reduce the polygon count. Import your file to Meshmixer and click
Select. Click anywhere on the object, then Modify > Select All > Edit > Reduce. Advance
the slider and choose a percentage to balance the detail you want with the number of
pieces you’re willing to glue together. Additionally, reduce the complexity of overly
detailed areas with a smoothing brush. Accept it and Export as .Obj. The example below
was reduced by 98%.
Notes for Unfolding in Pepakura
Within Pepakura change from letter size pages to large pages for big projects, as
above. Poster board may be cut to the maximum size of 17” X 28” on the Trotec Speedy
300, 60 watt laser cutter which converts roughly to 430 mm X 710 mm. Designate page
size in Settings > Print and Paper Settings > Other.
Be mindful of your model’s dimensions, making sure they remain the same from
document to document. Before clicking Unfold, record them. You may need the
reference since changing among various software and formats may affect scaling.
After the unfold add tab numbers by selecting 2-D Menu > Show Edge ID. Default
results may be too small to easily read. Adjust numeral size by selecting Settings >
Other Settings> Others > Font Size 8 > OK.
For better placement on your unfold pages, rotating pieces can be accomplished by
smaller increments than the 90° shortcuts. Click the rotate icon on the lower left toolbar
or right-click on your unfold for a drop-down menu.
Export your model using; File > Export > Vector Format> .EPS and also .DFX. Also
include Export > .PDO. The .PDO file will be needed for navigation while assembling
the parts. Export > Multi-Files .BMP for photo printing and photocopying. Existing
artwork can be retained on unfolded parts.
Prepare Pepakura Exports in Adobe Illustrator CS6 for Laser Cutting
This method entails combining two of Pepakura's export files into one, using Adobe
Illustrator, for the purposes of laser cutting.
The laser cutter will need colors called out in RGB. Establish a color hierarchy in which
the perimeter cuts last. If the perimeter cuts first, exhaust from the laser cutter's fan may
disrupt alignment before all the pieces can be numbered and scored. Tape your paper
or cardboard edges to the cut bed.
Colors in the table below are suggested for the Trotec. However, black must be used for
etching and red must be for the first cut. Pepakura’s default perimeter color is red so it
must be changed and placed last on the list. Etching takes too long. Cut everything.
Layer
Etching
Numerals
Mountain
Valley
Perimeter
Color
black
red
blue
teal
green
R
0
255
0
0
0
G
0
0
0
255
255
B
0
0
255
255
0
Method One. To change the color of all the occurrences of a particular line type; select a
line, click Select > Same> Fill and Stroke, as shown in the picture below. Change the
color by double-clicking the stroke box and assign RGB values to those listed in the
table above. Click outside the box to affirm the color changes on screen. See table p.4.
Step One; Designate Colors
Open your Pepakura .Dxf file in Adobe Illustrator with a scale confirming that 1unit = 1
mm.
Select > All, record the Height and Width, found in the transform panel at the top right of
the screen. Numerals and dashes will be added after changing line colors.
Change all colors to those in the table above by using Method One above. Save As >
Colors .Ai.
Step Two: Add Numbers
Numbers must be copy/pasted from the Pepakura’s .EPS file, to Colors .Ai, as follows.
Open your Pepakura .EPS file in Illustrator. Select one of your model's tab numbers. Be
certain no lines are selected. Isolate it within a bounding box, or underlining will do. See
above. Selecting the remaining numbers by use of Method One, above.
Edit > Copy the still selected numbers and paste them to, Colors .Ai.
Check for proper alignment of the two files. If they need adjusting click Object> Group
while still selected. Click Window > Align for the Align Box. Click the Horizontal Align
Center icon then the Vertical Align Center icon. Fine tune the alignment by using your
keyboard’s arrow keys. If necessary, change their settings in Edit > Preferences >
General > Keyboard Increments. Change all numerals to red by the use of Method One,
above. Confirm that, Fill, is set to, None. Save As > Numerals .Ai.
There will be no differentiation between Mountains and Valleys after cutting if no further
steps are taken. EPS dashed lines are actually solid lines with raster dashes added for
appearance which means they won’t cut as dashes. Use Adobe Illustrator to change
Valley lines to vector dashes, as described in step three.
Step Three; Dashed Lines
Open, Numerals .Ai in Adobe Illustrator.
To select all of the Valley lines, begin by selecting one Valley line. Click Select > Same
> Fill and Stroke. Wait for it. In the, Window > Stroke dialogue box, check the, Dashed
Line box. In the first dash box enter a value of 6 pt. Change the dashes to editable
paths by clicking Object > Path > Outline Stroke. In the upper left of the screen change
the fill to, none, and the stroke to red. In the stroke box, enter a stroke weight of .001
mm and click Enter. Save As > Dashes .Ai.
Step Four: Copy Pages to Separate Files
Open Dashes .Ai in Illustrator and Select All to check the scale. Carefully select and
copy Pepakura's, unfold page one, separating it from the others as follows.
Since Pepakura squeezes pages very close together for export, place one within a snug
art board beforehand, as above, to help with accuracy in the separating process. Use
the Art board Tool, designated by the # icon, found in the vertical tool bar, to size it
properly. Zoom in to check the perimeter for accuracy. Any points outside it will be
eliminated. Copy > Paste to a new document. Designate a Stroke Weight of .001 mm.
Orient to landscape by: Object > Transform > Rotate. Size the art board properly and
Save As > Page 1 .Ai. Create similar files for the remainder of your pages. These files
are ready to cut.
Pepakura’s exported .BMP files, containing fused or baked texture mapping, may be
color copied to standard page size or photo finished to poster size. Costco’s largest
photo print size is currently 16”x20”.Precisely align these pages on the laser cut bed
with their Trotec cut files. The result will be photo finished unfold pieces to assemble.
Trotec settings for poster board and large photo paper: