Lathe Information

ACER Lathe Digital Readout Basics

Basic Cutting Tools

Outside Diameter Cutting Tools:	Boring Bars for internal turning:
Carbide Insert Types:

How to Choose the Correct Turning Insert

Positive Rake -vs- Negative Rake Inserts

Basic Lathe Operations

Facing Facing is advancing the cutting tool perpendicular to the lathe's axis of rotation (along the X-axis). This creates a flat surface on the end or shoulder of the workpiece. Normally preformed with a Right-Hand Cutting tool. Use a Left-Hand cutting tool for heavy cuts. Do NOT use a Parting Tool or this operation!	Turning Turning is advancing the cutting tool along the length of the piece (along the Z-axis). This can be used to reduce the diameter of a part, create shoulders or create tapers. It is preferred to use a Right-Hand Cutting tool, on occasion a Left-Hand cutting tool will need to be used. Do NOT use a Parting Tool or this operation!	Parting & Grooving Parting & Grooving is normally advancing the cutting tool perpendicular to the lathe's axis of rotation (along the X-axis) in order to sever or recess a section of the workpiece. Parting through the workpiece is also known as a cutoff operation. On occasion, Parting & Grooving is preformed along the Z-axis.
Drilling Drilling uses a drill bit mounted in the tailstock of the lathe to create a hole in the end of a workpiece. Normally an 120° Spot Drill is used before using an 118° point Jobber length drill bit. When using a Machine Length or Stub Length Drill bit the Spot Drill operation can normally be discarded. Countersinks and counterbores features are created using this same method.	Tapping Tapping is a process of create threads on the inside of a hole using a cutting tool called a tap. Use a spring-loaded tap guide mounted in the tailstock and a tap mounted in a tap holder. The tap is then turned by hand to create the threads. Never turn on the lathe for this operation!	Chamfering Chamfering involves creating an angled surface at the edge of the workpiece or a shoulder. It can be done by feeding a 45° cutting bit along the X- or Z- axes into the workpiece, feeding a cutting tool at an angle, or with the DO One function on the TRAK lathes. For conventional lathes, a 45° cutting bit is easyest to use. For the TRAK lathe, use the Do-One function.
Reaming Reaming uses a reamer mounted in the tailstock to accurately finish a hole at the end of the workpiece. Drill the hole approximately 2 to 3% undersize. Use the correct cutting speed & Feed.	Threading Threading creates an external or internal thread on the surface of a workpiece, this is done by synchronizing the feed of the cutting tool with the rotation speed of the lathe. Ask the shop staff for help with this operation! Set the correct carriage feed settings. Use the threading dial to synchronize the carriage to the spindle location. Use a 60° threading tool.	Boring Boring involves the use of a boring bar to create a large inside diameter in a workpiece. This process allows for a precision hole to be created at any desired size. Boring bars are also available for internal grooving and threading.
Knurling Knurling creates a texture patterned of straight or angled lines on the surface of the workpiece. This process is normally used for adding a griping surface on tools, distorting the surface of the workpiece were an interference fit is needed, or for decorative purposes.	Profile Turning Profiling involves creating more complex shapes in a workpiece. A Profile cutting tool is normally needed for this type of operation.	Form Turning Form turning involves using a specifically created cutting tool to create more complex shapes in the workpiece. Form turning requires a custom cutting tool that is machined, hardened, and ground.

Facing

Facing is advancing the cutting tool perpendicular to the lathe's axis of rotation (along the X-axis). This creates a flat surface on the end or shoulder of the workpiece.

Normally preformed with a Right-Hand Cutting tool.
Use a Left-Hand cutting tool for heavy cuts.
Do NOT use a Parting Tool or this operation!

Turning

Turning is advancing the cutting tool along the length of the piece (along the Z-axis). This can be used to reduce the diameter of a part, create shoulders or create tapers.

It is preferred to use a Right-Hand Cutting tool, on occasion a Left-Hand cutting tool will need to be used.
Do NOT use a Parting Tool or this operation!

Parting & Grooving

Parting & Grooving is normally advancing the cutting tool perpendicular to the lathe's axis of rotation (along the X-axis) in order to sever or recess a section of the workpiece.

Parting through the workpiece is also known as a cutoff operation.
On occasion, Parting & Grooving is preformed along the Z-axis.

Drilling

Drilling uses a drill bit mounted in the tailstock of the lathe to create a hole in the end of a workpiece.

Normally an 120° Spot Drill is used before using an 118° point Jobber length drill bit.
When using a Machine Length or Stub Length Drill bit the Spot Drill operation can normally be discarded.
Countersinks and counterbores features are created using this same method.

Tapping

Tapping is a process of create threads on the inside of a hole using a cutting tool called a tap.

Use a spring-loaded tap guide mounted in the tailstock and a tap mounted in a tap holder.
The tap is then turned by hand to create the threads.
Never turn on the lathe for this operation!

Chamfering

Chamfering involves creating an angled surface at the edge of the workpiece or a shoulder. It can be done by feeding a 45° cutting bit along the X- or Z- axes into the workpiece, feeding a cutting tool at an angle, or with the DO One function on the TRAK lathes.

For conventional lathes, a 45° cutting bit is easyest to use.
For the TRAK lathe, use the Do-One function.

Reaming

Reaming uses a reamer mounted in the tailstock to accurately finish a hole at the end of the workpiece.

Drill the hole approximately 2 to 3% undersize.
Use the correct cutting speed & Feed.

Threading

Threading creates an external or internal thread on the surface of a workpiece, this is done by synchronizing the feed of the cutting tool with the rotation speed of the lathe.

Ask the shop staff for help with this operation!
Set the correct carriage feed settings.
Use the threading dial to synchronize the carriage to the spindle location.
Use a 60° threading tool.

Boring

Boring involves the use of a boring bar to create a large inside diameter in a workpiece.

This process allows for a precision hole to be created at any desired size.
Boring bars are also available for internal grooving and threading.

Knurling

Knurling creates a texture patterned of straight or angled lines on the surface of the workpiece.

This process is normally used for adding a griping surface on tools, distorting the surface of the workpiece were an interference fit is needed, or for decorative purposes.

Profile Turning

Profiling involves creating more complex shapes in a workpiece.

A Profile cutting tool is normally needed for this type of operation.

Form Turning

Form turning involves using a specifically created cutting tool to create more complex shapes in the workpiece.

Form turning requires a custom cutting tool that is machined, hardened, and ground.

Setting Tool Zero & Turning Procedure for Conventional Lathes

NPGR Insert Speeds and Feeds Information

Surface Finish & Nose Radius Selection

Parting & Grooving Strategies

When parting through, reduce the feed rate to 0.05mm/min(.002"/min) for the last 2mm(.08") of the workpiece diameter.

Cut-Off Insert Speeds & Feeds

Cut-Off Insert Widths

General formula for selecting insert width on common steel materials:

Diameter	Width
5 - 22mm	DOC/5
23 - 40mm	DOC/7.5
41 - 63mm	DOC/8.5
64 - 80mm	DOC/9.5
81 - 120mm	DOC/13
121 - 160mm	DOC/17

DOC is the depth of cut.

Cut-Off Insert Feed Rate Near Center

Lead Angle for Eliminating Burrs

Troubleshooting

Turning Wear Patterns

Rotational Speed vs Chip Color

Chip color is similar to the material color, this indicates that the appropriate speed/RPM is being used.
Copper color is indicating that the cutting speed is at the upper end of the cutting tools limit.
Blue is an indication of the speed being too high, reduce the RPMs before cutting tool failure.
Purple is screaming, "WAY TOO FAST…". Failure to reduce the speed immediately will result in very BAD things!

Work Support

Live Center

A Live Center is used when a part is to be turned and it is protruding approximately 3+ times its diameter away from the chuck or collet. A live center will be required to keep the shaft from deflecting while turning the part. Note: a 60° combination drill & countersink will need to be used to prepare the part to except the Live Center.

Steady Rest

A Steady Rest is used when a part is to be turned near the end, faced, and/or bored with its length being approximately 4 times its diameter or longer.

TRAK Lathe Information & Videos

Small Step & Do Ones Calculator

Click here to open the above calculator.

Videos

Please click here to view the TRAK Lathe Videos.

User Manual

Bridgeport EZ-Path Lathe

Basic Instructions

Programming the Machine

Create a .NC file using a Generic HAAS Turning post in a CAD software package.
Run the .NC program through the Bridgeport_ez_Path Post.exe converter and save it as a .PGM file.
- Notes:
  - The .NC code must be in Inches!
  - This converter supports both R and I, K formats.
  - This converter does NOT convert threading toolpaths!

...Download the Converter File Here... Once downloaded, change the .txt extension to a .exe extension and run the program.

Complete Operations & Programming Manual

page revision: 189, last edited: 09 Apr 2026 19:25

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