Introduction: Digital Manufacturing - Laser Cut Box Project

About: Fixer, Finder, Fabricator. I teach engineering to high school students, at St Marys Secondary College in Nathalia VIC Australia

This is the forth in a series of Instructables on how to use CAD (Computer Aided Drawing) and CAM (Computer Aided Machining)
if you have been following along you should be getting quite good at using prodesktop so there is not as much detail in the photos and we will be focusing more on the design part of the program as engineering drawings and photo album have been covered in the first three instructables.
This project is a simple laser cut box which little kids love to play with, or you can cut it out of clear and use it to display an object.

If you haven't seen project one, take a look as it covers where to get the Prodesktop, how to activate the software, how to navigate the screen, what you will need and the mouse functions.

Digital Manufacturing - project one Key tag
Digital Manufacturing - project two desk name plate
Digital Manufacturing - project three 3D printed box
Digital Manufacturing - project five printed toy car

As computer tutorials don't translate to text very well, for this series of instructables most of the info is in the photos. So click on the first photo and use the arrows to go to the next photo. The boxes in the photos show the location of the icons and have have text in them when you hover the mouse on them.

Step 1: Learning Intentions and Success Criteria

Learning Intentions

  • To work safely in the workshop
  • To improve my understanding of how the CAD software works
  • To operate a laser cutter

Success Criteria

  • I understand the safety rules and I am working safely in the workshop.
  • I can produce 2D and 3D CAD drawings and convert them to a DXF file.
  • I can produce an assembly drawing.
  • I can produce a photo album drawing of my project.
  • I can operate a laser cutter safely and work safely in the workshop.

Step 2: Designing the Front and End

As a normal box has six sides it may surprise you to know you only really need to design the front and end of the box. The top and bottom just need to be traced.
A couple of things before you start, if you make the box too big, it may not fit on the laser cuter, so think a ahead, will six sides and the lid all fit on the bed of the laser? The other problem with making a large box out of acrylic is the material is not very strong so a large box is more likely to break if it  is dropped or handled roughly.
Also fitting legs to  box will help protect the bottom from scratches and also help the box to sit flat on a surface.

Ok let get started, click on the photo and use the arrows to follow along.

Step 3: Assembling the Front, Back and Ends

Assembling the front, back and ends is required to set up the next step and is the easiest way to get the design of the top and bottom correct.
We need to keep our 2D drawing so cut and paste the parts into new designs, and is is also important to get the parts correctly orientated so we will be using the "work-plane new sketch" command

As always click on the photo and use the arrows to follow along.

Step 4: Tracing the Top and Bottom

We are going to sketch in the assembly drawing, tracing the top and copying it into your 2D drawing and a new design. It important that after you do this, that you delete the sketch from the assembly drawing. You can then extruded the bottom and fit it to your project.

click on the photos...

Step 5: Designing the Handle and Final Assembly

In this step we are gong to copy the front, end, and bottom, and design a handle for the top. You can then copy the handle and top into new designs and extrude, then assemble the last two parts of your project. This is the time to check your project to make sure everything fits and it looks the way you want.
If you have a problem when assembling a part often is is easier to delete the component and  add it again

Click on the photo to begin

Step 6: Speeding Up Cut Time and Exporting to DXF

This step will show you how to move the pieces around to minimize the cut time of the laser and reduce the amount of material waste. If you are hiring a laser this will reduce the cost of your project, as the cut time is reduced, and if you have your own laser your increasing the life span of your equipment.
It is important that you delete the "lines on top of lines" as if you don't the laser will cut in the same place twice.
This step also covers how to export a DXF file which is the format the laser cutter needs to cut out your project.

click on the screen-shots...

Step 7: Laser Cuttting and Glueing

Once you have laser cut the box, it can be glued together. A cotton bud works well to apply the glue but make sure that you get the glue on the right edges. It also helps to tape the sides on while the glue drys and sit the box on a flat surface so the box doesn't rock around after the glue drys.