Jul 5 11

AJAX CNC How To Retrofit


How to Retrofit a Bridgeport Boss

  Finall Boss Retrofit

This Bridgeport Series II mill, originally equipped with a BOSS 5 control, began experiencing drive problems very common with aging BOSS systems. Instead of spending $1800 to replace each of the stepper drives, an AjaxCNC control was the obvious choice.

This page briefly describes the process of retrofitting your machine with an AjaxCNC control kit. The entire installation process took about 16-20 hours to complete. The end result is a servo-powered CNC machine capable of far more than the original control could ever do! All for around $5000.

The process below is not just specific to a Bridgeport BOSS, but applies to any AjaxCNC retrofit.

Step 1: Remove the Old Control

In order to prepare your machine for an AjaxCNC retrofit, you must first remove all of the old control components. This consists of the control, motor drivers, and power supply. If you are retaining your original servo motors, you’ll want to leave the motor transformer as part of your new power supply.

The items you will want to keep are the contactors, disconnect, fuses, limit switches, lube, and coolant. In the case of the Bridgeport BOSS, you’ll also retain the spindle speed up/down & brake air solenoids. All of these items can be connected to and controlled by the AjaxCNC control.

Bridgeport Step 2

Step 2: Install the Motion Control Card

The first step to building your own CNC is to Plug in the Ajax CPU10 motion control card into the PC’s motherboard PCI slot and snap/screw in place the PC breakout bracket and connect a few cable connectors to the board. This takes about 5 minutes.

Bridgeport Step 3

Step 3: Install the Hard Drive & Software

After installing the CPU10 card, you are ready to install the AjaxCNC software. The PC requirements for an AjaxCNC control can be found on the Ajax Software page.

The AjaxCNC control software as well as the Linux OS come preinstalled on a flash hard drive. Simply plug the new drive into the primary IDE slot on the motherboard and connect the supplied power connector.

Bridgeport Step 4

Step 4: Mount the New AjaxCNC Components

For this Bridgeport Boss retrofit, we have reused the sub-panel from the original control cabinet. We simply stripped off all the unwanted components and are now reusing the panel to mount our new AjaxCNC components. The AjaxCNC installation manual has a suggested panel layout drawing. It is only a guide for a typical layout, and you can easily move any component to an ideal position to accommodate the cabinet you are using.

Mount the DC3IO drive first, as it is the largest component. Once the DC3IO board is mounted, it’s time to bolt down a few contactors to the sub-panel. We have added a spindle motor reversing contactors. We could have reused the reversing contactors from the old control, but in this case they were pretty nasty looking, so we decided to install new contactors. Next to the reversing contactors we installed the E-stop and the Flood pump contactor (from left to right).

Bridgeport Step 5

Step 5 – Reinstall the Sub-panel into the Original Cabinet

Before bolting the sub-panel back on, we cut a rectangular hole with a jig saw in the back-facing side of the electrical panel to give us a way to run all our axis motor cables, limit switch wires, spindle power, speed up/down/brake, lube pump and flood pump cables through one hole. This eliminates the need for multiple holes and strain reliefs. We also cut another rectangular hole in the back-facing panel for access to the control computer’s floppy/CD drives. We then fabricated a simple latched and hinged door that covers the hole while the floppy/CD are not being used.

In this photo we have just put the PC into place and ran the motor cables through the new hole in the back of the cabinet.

Bridgeport Step 6

Step 6: Hook Up the Components

Once all the components are in place, it is time to hook them up! Just follow the full-size wiring schematic included with your AjaxCNC kit. Simply connect up the components to the labeled outputs on the DC3IO. No special tools are required for the job.

The orange input/output connectors you see in the picture are very convenient to use. They unplug from the DC3IO and directly accept wire with no crimp-on connectors necessary. You’ll use these to hook up all the machine accessories to the Servo Drive/ PLC board.

The two small green boards to the right of the flood contactor are extra relay output boards that are included with the Boss control kit. They are used to control the stock Spindle Speed UP/DN and Brake air solenoids. A special Boss PLC program is supplied. All the Bridgeport PLC programming is done for you.

Bridgeport Step 7

Step 7: Mount Display, Keyboard, & Control Pendant

We have retained the stock control console support arm. We didn’t even have to remove it from the machine. For this install we made a simple steel box to house the color 14" VGA display and PC keyboard. We also permanently mounted the CNC machine control pendant to the right of the display.

Alternatively, we also offer a mounting arm for the keyboard and monitor. This includes a place for the pendant.

Bridgeport Step 8

Step 8: Ready for Check-Out

Be sure to inspect each and every connection before powering up the system for the first time. Once you feel confident in your work, you are ready to configure the machine.

Bridgeport Step 9

Step 9: Configure the New AjaxCNC Control

All that’s left is to do is power up and set up the machine configuration. With an AjaxCNC control it’s simple to set the turns ratio (screw pitch and pulley ratios), set the backlash of the machine (the control will remove unwanted backlash), set up the travel limits (the control will know the travel limits of the machine), and tune the servo motors. The digital DC3IO is self-tuning. It automatically sets all the axis motor parameters for the best possible machining performance in just a few minutes! Unlike the competition, our digital servo drives have no trim pots to adjust.

Bridgeport Step 10

Step 10: Start Making Chips!

Here is one of the first parts made on this machine with the new AjaxCNC control. Intercon conversational part programming (included with all AjaxCNC kits) was used to produce this part using the extensive canned cycles included in Intercon. The canned cycles used for this part were: Drill, Drill Repeat, Chip-Breaking, and Counter-Bore. In addition, the Mirror and Repeat cycles were used to take advantage of a symmetrical part therefore reducing programming time and effort.