OnShape CAD and Laser Cut Tabbed Boxes
Onshape has become one of the most popular CAD platforms because of its ease of use, powerful features, and ability to run on the cloud. We use Onshape in our classes here to teach concepts of design, precision, and engineering communication. We recently discovered a couple tools that allow you to quickly generate the tabbed box artwork directly from Onshape for your laser. In this guide, we'll walk you through just a few of the basics.
Onshape FeatureScript Add-ons
FeatureScript is the programming language designed by Onshape for automating parametric models. There are two FeatureScripts that we'll use for creating the tabs and generating the artwork for laser cutting.
There are several copies of these add-ons. I don't know how important it is, but the ones we used are:
FeatureScript: LaserJoint v1 - Auto-generates tabs on parts that intersect.
FeatureScript: Auto Layout v3.1 - Flattens your design and lays it out onto a sheet for cutting.
Search for these under the add-ons on the far right of the toolbar menu. Click on the FeatureScript once to add it. Note: if you click it a second time, it will remove it from your toolbar.
After adding these, you'll see the new tools under the pull-down menu on the far-right side of the tool bar. You only need to do this step once. The next time you open Onshape, these tools will automatically be available.
Building the box
To start, we will create a five-sided open box. Each of the five sides of the box must be a separate part.
Step 1- Create the base:
Sketch with a rectangle to form the base.
Make the dimensions of the base equal to the width and length of your box. In this example, we'll make it 3" x 4". (Length x Width)
Click the check to finish the sketch.
Step 2 - Extrude the base sketch
Click the extrude tool or (SHIFT+e).
Extrude it upward a thickness of 0.125"
Make sure that the Extrude is set to create a New part.
Click the check to finish the extrude.
Right click on the part (Part 1) in the Parts Tree on the left hand side and rename it Base.
Step 3 - Build the sides
Step 3a - Create the sketch
To build the sides, rotate the view so that you can see one of the edges. Start another sketch on this edge.
Draw a rectangle that will be the size of this side.
In this example, we make it 4" x 1.5". (Width x Height)
Click the check to finish.
Step 3b Extrude to make a new part
Click the extrude tool or (SHIFT+e).
Select the entire sketch and extrude it inward a thickness of 0.125" so that it overlaps with the base.
Make sure that the Extrude is set to create a New part.
Click on the check to complete this step.
Repeat this step for the other three sides until you have an open 5 sided box.
Five-sided Open Box
You should now have a box with five intersecting (overlapping) sides that are each 0.125" thick.
If the sides are not intersecting, double check the direction of the extrude you did in the previous steps. Each extrude should go into the base.
You should also have five separate parts. If you don't double check that each extrude feature resulted in a "New Part" as opposed to "Add to Part".
Last, clean-up your drawing by making sure each part is named. I use these general conventions in naming my design:
Base
Right
Left
Front
Back
Making the Tabbed Finger Joints
Now, to make the sides of the boxes tabbed, we'll use the Laser Joint FeatureScript you added.
Click the Laser Joint Tool from the Custom Features Toolbar
On the pop-up, select Automatic
Now, select each of the five pieces of your box.
Set the number of pins to 2 or more.
Add an Allowance of -0.005 in. for the kerf of the laser.
Click the checkmark to finish.
When you are done, you should see the tabbed box with the tabs overlapping by 0.005 in. to account for the laser kerf.
Click the check to finish the laser joint tool.
Creating the Artwork for Laser Cutting
Now, to generate the artwork for laser cutting, we need to flatten the sides of the box. To do this, we'll use the Auto-Layout FeatureScript Tool
Click the Auto-Layout Tool from the Custom Features Toolbar
Set the thickness of the material to 0.125"
The script will use the sheet width / height to layout the most efficient layout.
For this example, set the sheet width to 12" and set the sheet height to 6"
Click the check to finish the Auto Layout tool.
Create a drawing for the laser cutter.
Last step is to create a drawing of the part studio. Drawings are 2D projected views and isometric views of your parts.
Click on the plus icon on the lower left corner to Insert a new element. Select Create Drawing…
Click Custom template and click Do not include the Border and Do not include Title Block
Set the page size to B.
A blank drawing will open. Click on the Part Studios icon.
Click on the Part Studio 1 to import the entire part studio.
Insert the entire Part Studio Layout to the drawing.
Set the view orientation to Top.
Set the scale to 1:1
Click on the drawing to set the view.
Tap ESC on the keyboard to exit.
Export Drawing as PDF
Right-click on the Drawing 1 tab and select Export…
Set the format to PDF.
Set the Options to Download.
The downloaded file can now be imported into Inkscape for additional modifications or directly to the Glowforge App for laser cutting.
