HelicopterJohn
07-16-2011, 08:58 AM
Hi,
I recently purchased a used Shopbot PRT 48 X 96 CNC Router. The previous owner had modified the unit to work with Mach 3 software. It had Gekco 202 geckodrive step motor drives. They were a little noisy, especially when running at lower speeds. It originally had a CNC4PC breakout board which successfully operated the Shopbot.
I cut a lot of plastics and had the need to reduce the spindle RPM in cutting this material. Being new to the DYI concept of CNC tools I did quite a bit of research on possible retrofits to bring new life back to this machine on various forums on the internet.
I decided to install a Super PID Speed control kit on the router with a minimum RPM of 5000 and still have good torque for cutting. I also decided to remove the current Shopbot control and make my own DYI control. The only remaining electronic items left were a couple of proximity switches and the Stepper motors.
I also installed the 2010 Screen Set for my Mach 3 software that is feature rich in that it allows you to do semi-automatic tool changes, probing etc.
Yesterday a friend in Florida helped me assemble and wire up all the electronic components. I couldn't have done this without his help. I used a PMDX-126 Multi-Mode Breakout Board, 2 each PMDX-133 Motherboards for mounting the new Gekco 203V geckodrive step motor drives, and a PMDX-107 isolated speed control which interfaced with the Super PID Speed controller. This allows me to have spindle RPM control via GCode that is run in the Mach 3 software. Using the 2 each PMDX-133 motherboards will allow me to use up to 6 drives. I also have 2 parallel ports one in the main CPU of my PC and also an add-on parallel port card in case I need any additional inputs etc. in the future. I hope to add a 4th axis sometime in the future.
I now have to install the components in a cabinet that my brother made for me and install appropriate cooling fans for the electronics.
The Shopbot now runs like a dream. QUIET and SMOOTH. The total cost for the retrofit was around $1500.00. All new electronics except for the stepper motors and a proximity switches.
John
I recently purchased a used Shopbot PRT 48 X 96 CNC Router. The previous owner had modified the unit to work with Mach 3 software. It had Gekco 202 geckodrive step motor drives. They were a little noisy, especially when running at lower speeds. It originally had a CNC4PC breakout board which successfully operated the Shopbot.
I cut a lot of plastics and had the need to reduce the spindle RPM in cutting this material. Being new to the DYI concept of CNC tools I did quite a bit of research on possible retrofits to bring new life back to this machine on various forums on the internet.
I decided to install a Super PID Speed control kit on the router with a minimum RPM of 5000 and still have good torque for cutting. I also decided to remove the current Shopbot control and make my own DYI control. The only remaining electronic items left were a couple of proximity switches and the Stepper motors.
I also installed the 2010 Screen Set for my Mach 3 software that is feature rich in that it allows you to do semi-automatic tool changes, probing etc.
Yesterday a friend in Florida helped me assemble and wire up all the electronic components. I couldn't have done this without his help. I used a PMDX-126 Multi-Mode Breakout Board, 2 each PMDX-133 Motherboards for mounting the new Gekco 203V geckodrive step motor drives, and a PMDX-107 isolated speed control which interfaced with the Super PID Speed controller. This allows me to have spindle RPM control via GCode that is run in the Mach 3 software. Using the 2 each PMDX-133 motherboards will allow me to use up to 6 drives. I also have 2 parallel ports one in the main CPU of my PC and also an add-on parallel port card in case I need any additional inputs etc. in the future. I hope to add a 4th axis sometime in the future.
I now have to install the components in a cabinet that my brother made for me and install appropriate cooling fans for the electronics.
The Shopbot now runs like a dream. QUIET and SMOOTH. The total cost for the retrofit was around $1500.00. All new electronics except for the stepper motors and a proximity switches.
John