KSA FAB LAB > CNC Routers / Microscribe

Overview of Shopbot Digitizer

The ShopBot's digitizing probe allows you to use your ShopBot to map the 3D shape of an object or to record the object's outline. The probe works by moving towards and just contacting the part with its stylus. At contact, an internal switch is triggered. The switch signals the software to record the 3D location of the contact point and move on to the next point.

Installation

The probe itself installs into the 1/4" collet of your spindle/router. The probe comes fitted with a 1/8" stylus that is a good general purpose size for probing an object and then cutting it with a 1/8" bit if you are scaling 1:1.

Secure the probe in the collet so that it does not rotate. If your spindle/router rotates easily, a piece of tape usually works well to keep it from turning.

Loading the Copy Machine

Your ShopBot Control Software comes with special tools to put the probe to use. After you complete the installation and are ready to probe an object, go to: Tools > Copy Machine.

The Copy Machine will first ask you a series of questions about what you want to do:

What kind of copying do you want to do? Do you want to scan the top surface of an object, or do you want to trace the edge of an object, or just generate a single contour of your landscape?

What are you going to use to copy your pattern? For this question, you should answer "ShopBot probe"

What kind of output file do you want to create? This is entirely up to you - for this tutorial, though, we will specify a DXF file of points - which will then be reverse-engineered using FormZ. You can also generate a ShopBot .sbp file directly, or a polyline DXF file.

3D probe settings
This screen asks you to define the general parameters you will use to scan your object: how big your object is, the maximum depth the ShopBot should reach, and how frequently it should look for points. For this example, we've chosen a 3" square object with a maximum depth of 4" below the Z axis. We'll scan points every 1/4" throughout that area. The last 4 fields, covering the speeds, input switch number, and tolerance, shouldn't be adjusted.

If you want to know more about any field on this screen, hover over its value with your mouse - a pop-up window will appear that gives you more information.

At this point, you will be asked to specify the file where your scanned data will be stored. It's best to pick a file on the local hard drive (D:/) rather than scan directly to your User folder or the Transfer drive.

Are you ready to copy your pattern now? The ever-helpful ShopBot will ask you to confirm that you're ready to scan your object before proceeding.

The ShopBot will ask if you want to move to a different location before starting your scan job. If you do, follow the instructions in this popup window - if the ShopBot is already positioned correctly, just click "OK".

Assuming you have done everything else correctly, you should now be ready to start - so click "OK" again and the ShopBot will begin moving.

At this point, the ShopBot software will begin using the digitizing probe to scan the top surface of your object. The time it takes to complete the job will depend on the size and resolution you specified under the 3D Probe Settings window above. For example, the settings used here (3" square, 1/4" resolution) took 8 minutes and 27 seconds to produce a scanned object. The resulting scan is pictured below as it appears in FormZ.