Bridgeport Mill Induction Checklist

Induction Check Sheet
Bridgeport Milling Machine
Inductee level of experience with similar machinery:
Safety	Completed Tasks
Personal Protective Equipment (PPE): When working with the milling machine ensure that you are dressed appropriately. Ensure that you: Do not wear baggy clothing. Do not wear any jewellery. Tie your hair back appropriately if it is long. Wear eye protection at all times. These all have the potential to get caught in the moving parts of the machine. The list is not exhaustive and it is on the operator to apply common sense.
Surroundings and Setup Check that: The machine is set up how you expect. Check: The locks for all 3 axes. The quill feed is engaged/disengaged. The spindle is set to turn in the direction you expect. Your work is clamped securely. If you find it set up in a certain way don't assume it's safe. The floor area you are working in is clear of cables, obstacles and potential trip hazards. Ensure there are no obstacles in the travel envelope of the tables. Wear eye protection at all times. These all have the potential to get caught in the moving parts of the machine. The list is not exhaustive and it is on the operator to apply common sense.
Preventative Maintenance Prior to using the machine please ensure to press the one shot oiler 3 times. It's on the left hand side of the machine, behind the table.
Main Controls The primary power switch for the machine is a big red rotary switch on the box on the right side. Vertical is on, horizontal is off. Facing the front there's a row of 4 switches. Up is on, down is off. Left to right, they control: Spindle ? ? ? I can't remember :) The primary power switch for the machine is a big red rotary switch on the box on the right side. Vertical is on, horizontal is off. Spindle direction is set by the switch on the top left of the machine. Left is clockwise, right is counterclickwise, middle is disengaged (looking down). Spindle speed is set by the 3 position pulley gearbox inside the spindle head.
Moving the Bed As you face the machine: The X axis moves left and right. The Y axis moves forwards and backwards. The Z axis moves up and down. Every axis has a lock. You may want to engage the locks to maximise accuracy, as machining forces (usually during heavy machining) can move the axes without user intervention. The X and Y axes are connected to the DRO. The X axis has an autofeed.
Changing Spindle Speed Consult the table on the front of the machine for your desired configuration. Stop the spindle. Set the spindle motor to disengaged by turning the spindle direction switch to middle. Loosen the belt tensioning lock. Move (rotate) the spindle motor to loosen the belt. Move the belt into the desired position. Move (rotate) the motor to tighten the belt. Tighten the belt tensioning lock. Power the spindle, ideally without a tool to ensure it rotates freely and sounds normal.
Changing Tool Stop the spindle. Set the spindle motor to disengaged by turning the spindle direction switch to middle. Using the spindle brake to lock the rotation of the spindle, use a spannner to undo the draw bolt until it is fully unscrewed. You will be able to feel it come free. Using a wooden, plastic, copper or otherwise not hard hammer, gently tap the top of the draw bar to free the tool from the spindle. This will cause the collet (and tool) to fall out. Ensure to support or cushion it appropriately. Brittle tools e.g. carbide can crack from falling short distances onto metal surfaces. Insert a new collet. Tighten the new collet. Set your desired spindle direction. Power the spindle to verify the spindle rotates freely and the machine sounds normal.
Digital Read Out (DRO) The DRO simplifies precision positioning your work relative to the tool. A typical DRO workflow may look like: Jog your tool very slowly until you hear it start to touch your work. For the axis, set the DRO to minus half the tool diameter. Repeat for all axes (so just 2 usually). Jog X and Y to 0. The center of your tool is positioned above the datum of the workpiece. The DRO supports: Metric and Imperial units. Setting an axis to a arbitrary value. Adding or subtracting arbitrary values to the current readout. Polar coordinates.
Rapid Feed Rapid feed can be used to jog the machine quickly, and to ensure a constant feed rate (amd therefore an even surface finish). The controls are: Power: Switch on the front panel. Up is on, down is off. Speed: Rotary dial on the control panel on the right. Speed is logarithmic so don't just crank it to the max. Direction: Left/middle/right lever on the right of the bed.
Quill Feed The quill feed allows the spindle to operated like a pillar drill. During normal machining, the quill feed should be locked using the rotary lever on the front of the machine head. To operate the quill feed, disengage the quill feed lock. Make sure to lock the quill feed after you finish using it. The quill feed has limit nuts that can be adjusted to get a repeatable drill depth.
Cleaning up Please ensure you clean and tidy the machine after you finish working. Ensure that: The main power is off. All the switches on the front panel are off. The bed is free of swarf and debris. There is no tool in the spindle. The autofeed is set to disengaged, i.e. in the middle position. The spindle motor is disengaged via the middle position on the spindle direction switch. The quill feed is retracted and locked.