ShopBot Tools

Technical Q & A

I'm experiencing intermittent position loss in random axes

Most Common Problem: Computer Interference:

PC Setup
The PC setup can be daunting to many users, and you may need an IT professional to help you, but to succeed with the ShopBot and have it work as smoothly as possible, the control computer must be set up accordingly.
If you are in an educational setting you need your IT dept to provide you a standalone workstation that is not managed by group policy or on the network.

For all applications, the PC must be a clean installed standalone workstation. This will wipe/delete all data/files/programs from the computer.

For the workstation setup a clean install is needed, below is our best information on how:

--- Computer Requirements -
Installing Windows with USB Installer -
Installing Windows with CD -
Setting up Control Computer -
Installing the Control and Design Software -

1.)    Make sure we are not using a port that is 3.0 if earlier than Windows 10. This is usually a blue colored port or labeled with an SS icon or will just say 3.0 or USB 3.0. We do not want to use this. It is not going to be compatible with the controller. USB 3.0 is fine for windows 10
2.)    Make sure the usb cable is not over 10ft or extended in any way.
3.)    Make sure the usb port is connected directly in the computer and not a hub.

Electrical Interference

Make sure the cabling for the tool is laid straight and flat without loops/coils. Do not put extra cable in the box.

Ensure the power cable for the cutting head is separated from the other cabling by at least a 1" air gap over the entire course of its run.

Ground tool – usually grounding dust collection system is sufficient. Otherwise, may want to ground table bed (PRT tools only).

Grounding dust collection

Links on Dust Collection Grounding

Ideally, use a hose that has copper core wire.

Otherwise, coil a wire up into the hose (this is not ideal).

Connect the copper wire to a large metal object or building ground (preferable) at the dust bag end.

Also make sure the metal body of the dust collector is grounded.

DO NOT have any metal connection running between dust collection and tool – this will cause static to be discharged to the tool rather than away from it.

Other Solutions

Load Firmware.

Check Com Speed.

Check if tool is looking at the wrong port.

Check if the driver is actually loaded.

Check if the excess motor cables are looped up inside the control box.

Check to see if the low voltage sensor cables bundled with the motor cables/power cables.

Check if USB-Serial adapter is dead.

Checking Communication Speed

Depending on the version of the software, perform a baseline test on the communication speeds for the tool. If the version is unknown, check the ShopBot software’s Command Console under Help->About.

This only tests the USB/Serial connection, it does not test the PC in any way.


For 3.8.x versions, perform a move command over a distance of 12 inches. Do this through the command console and not the Keypad by typing a command like: MX, 20 (Move->X axis, 20 inches).

After the move command completes, go to Utilities->Diagnostic Information. The last value on the bottom right of that list should be a value called Packet_et. This is a rough check on how long a command takes to communicate with the controller. This should result in a value of ~35 or less.


For 3.6.x and lower, there should be a program in the C:\Program Files (x86)\ShopBot\Diagnostics folder called USB Speed Test. Perform the test and the tester will display a percentage. The percentage should be 75 or greater.


If these tests result in a poor communication speed, replace the cable connecting the PC to the tool.

Need additional information? Let us know

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ShopBot Tools, Inc.

Toll Free: 1-888-680-4466

Phone: 919-680-4800
Fax: 919-680-4900

ShopBot Tools, Inc.
3333-B Industrial Drive
Durham, NC 27704

Office Hours
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After Hours Tech Support
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Saturday–Sunday: 10am–5pm EST

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