The most popular and versatile knee mill ever produced, setting the standard in manual milling.
The Bridgeport Series 1 Knee Mill is the original milling, drilling and boring machine with over 370,000 machines built over the past 70+ years.
Built the Bridgeport Way
The long-term reliability of a Series 1 mill is the result of its design features, the quality of its components, and the craftsmanship of its hand-scraped ways and precision ground fits. Every Bridgeport knee mill is built as though we’re going to use it ourselves. That’s why the resale value of a Bridgeport mill remains consistently high. The “bargain” imitators can’t say that. Our competitive prices are a result of our higher volume—not from building a cheaper machine. Rigidity starts with the main frame components of a machine, and for this reason, the strength and damping qualities of gray cast iron was chosen.
Patented 2J head
The unique and patented air cooling system of the “2J” head ensures that any heat buildup in the spindle bearings, belt or quill area is kept to an absolute minimum. This is achieved by air being drawn into the belt housing and past the spindle bearings by the rotation of the drive belt. It is then exhausted out of the head assembly at the top of the casting.
Distortion and inaccuracy due to excessive heat rise is kept to a minimum by maintaining the operating temperature within 20 degrees fahrenheit of ambient temperature. This also results in increased belt and bearing life, as well as more consistent accuracy. Also, with no external cooling fans, vibration is reduced and the ongoing maintenance or threat of a fan failure is eliminated. Fans also frequently require a step-down transformer if the machine is wired for power greater than 110 Volts.
Series 1 One-shot lubrication
Adequate lubrication ensures a long accurate life for the machine. It also reduces maintenance and makes the machine more sensitive and easier for the operator to use. A metered, centralized system lubricates all of the ways and screw assemblies of the machine. Operation of the system by a single lever saves the operator time and makes it easy to always provide the correct amount of oil, predetermined by a series of metering valves built into the system.
Many competitive systems do not meter lubrication, which allows sliding member may receive more oil than another, possibly causing excessivewear to the area that is not getting properly lubricated. An optional Automatic Lubrication System is also available.
Hand-scraped ways
All alignment ways and gibs are completely hand scraped to within tenths of a thousandth. This ensures optimum machine geometry, rigidity and accuracy.
Bridgeport’s signature painting process
Castings are fully inspected, shot blasted, annealed and oxide coated, totally free from rust and contamination. They are then spray filled, sanded and painted with part polyurethane coating to seal the castings. Painting before machining builds the depth of gloss, which is required of all Series I machines. The last process prior to skidding for shipment is to spray a final finish coat of the best polyurethane coating available.
Machine Specification
Table & Ways Table Size 49” x 9”
No. of T-slots 3
T-Slot Width 2.5”
Table Ways Dovetail
Knee Ways Dovetail
Column Ways Dovetail
Max Table weight 340lbs
Travels X Longitudinal 36” (33” with power feed)
Y Cross 12”
Knee 16”
Ram 12”
Motors & Spindle Spindle Motor 3Hp
Variable Spindle Speed rpm 50-3750
Low Range 50-420
High Range 420-3750
Main Spindle Taper R8
Spindle Travel 5”
Quill Feed (mm/rev.) .0015 / 0.003 / 0.006 in/rev
Head
Swivel (R&L) +/- 45deg
Head Tilt (Up/Down) +/- 45deg
Dimensions & Weight
Overall Height 87”
Net Weight 1930lbs
Standard Equipment
- Patented air cooling 2J Head
- Hardened Chromed, X, Y & Z Ways, hand scraped for precision
- T-slots are ground to provide reference edge for positioning your workplace
- Hardened & Ground Table Surface
- Hardened & Ground Spindle
- Coolant System w/Pump & Switch
- Flexible Segmented Coolant Nozzle
- 7/16” Imperial Drawbar R8
- Variable Speed Drive
- Articulating Head for Compound Angles
- Worm gear angular positioning of head in two directions
- Lever-operated manual rapid quill movement
- Handwheel for fine quill feed
- Adjustable automatic feed disengagement for quill feed in both directions
- Micrometer depth stop
- Reversing switch for clockwise or counter clockwise operation
- R8
- Spindle Brake (Hand operated)
https://www.colchester.co.uk/products/bridgeport-series-1-knee-mill/
