CNC Lathe

CNC Lathe

A small CNC training lathe from the early 90s retrofitted to work with LinuxCNC.
Equipment Information
Status	Unknown
Manufacturer	Boxford
Model	TCL 160
Hackspace Information
Induction Required	No
Card RFID Enabled	Not yet
Owner	Aidan

This small CNC lathe is a Boxford TCL160 that has been stripped of its original electronics and now runs from LinuxCNC. Work can be held in an ER40 collet or a 3 jaw chuck.

https://youtu.be/iYVwLWzdDlU

Induction

You must be a Hackspace member and a competent, inducted user of the traditional metal lathe. Arrange an induction on the CNC mill to get started, and ask Aidan for pointers via email.

Gearing

There are four speed settings, changeable by a series of pulleys in the gear cover. To change gear during a program you must use the following series of commands. If you change the gear setting without changing the gear on the controller, or vice versa, then the actual spindle speed will be greatly different to the commanded spindle speed.

Change the gearing to increase the torque available to the motor for operations like grooving, threading and parting.

Gear	Command	Min. Speed	Max. Speed
1	M101	320	3200
2	M102	160	1600
3	M103	80	800
4	M104	40	400

Fusion 360 Configuration

You can find a tools file for importing into the Fusion 360 tool library and a post processor on the Google Drive.

Tools

This lathe doesn't have a automatic tool turret, so tools must be changed manually. For this reason it's important to order operations that allow the minimum changing of tools while still allowing for secure work holding.

The tool holders with numbers engraved on them have had offsets set in the controller and are known to cut accurately. If you are working on something important it is recommended that you buy your own inserts and swap them out when appropriate. If you break a communal insert please buy a new one.

Tool Offsets, or, do not move the tool in the tool holder

The tools have specific offsets set in the software, listed below. If you move the tool in the holder even a little bit then you will need to reset the offsets which is, frankly, a massive pain. You can find suggested Surface Speed settings in this table: CNC Lathe/Inserts

Fore more information on setting the offset for a tool, please ask. Also read the relevant section of the LinuxCNC documentation.

#	Insert Type	Offsets	Usage
1	CCGT 09T302		General turning and facing.
2xx	External Threading Tools		Where xx is the pitch of the thread insert. General turning and facing, specifically for shaping.
300			Parting & grooving, 2 mm width, with a slight radius. Straight cut.
301			Parting. 2 mm width, with a slight radius. Angled cut with the intention to part off with minimal nub on the part.

Hazards.

• 1) Chips in eyes.
• 2) Hair or clothing caught in rotating parts.
• 3) Cutting tool breaking or getting ejected from holder.
• 4) Sharp objects and chips cutting fingers.
• 5) Objects ejected from chuck.

Persons at risk.

• Operator.
• Persons nearby.

Initial assessment of risk.

Hazard identified	Severity	Probability	Risk Factor
Chips in eyes	3	2	6
Hair or clothes caught in chuck	2	2	4
Cutting tool breaking	2	2	4
Cuts from sharp objects	1	3	3
Objects ejected from chuck	1	3	3

Control measures.

• Users will be required to attend training to learn how to use the machine safely.
• Check everything is secure before starting the motor.
• Users will be trained to mount the cutting tools and work pieces safely.
• Always use a brush to clean away chips and swarf.
• A safety cover is in place for operation and includes a safety interlock

Final assessment of risk

Hazard identified	Severity	Probability	Risk Factor
Chips in eyes	3	1	3
Hair or clothes caught in chuck	3	1	3
Cutting tool breaking	2	1	2
Cuts from sharp objects	1	1	1
Objects ejected from chuck	1	1	1

Points system

Hazard severity	Points Rating	Definition
Nil	1	Very minor injury, bruise, graze, no risk of disease.
Slight	2	Minor injury, which would allow the individual to continue work after first aid treatment on site or at a local surgery. The duration of the stoppage or treatment is such that the normal flow of work is not seriously interrupted.
Moderate	3	Temporary disability causing injury or disease capable of keeping an individual off work for three days or more and reportable under RIDDOR
High	4	Causing death, serious injury or permanent disability to an individual.
Very high	5	Causing multiple deaths and widespread destruction eg. fire, building collapse.

Hazard likelihood	Points Rating	Definition
Remote possibility	1	There is really no risk present. Only under freak conditions could there be any possibility of an accident or illness. All reasonable precautions have been taken - This should be the normal state of the workplace.
Unlikely	2	This incident or illness might occur but the probability is low and the risk minimal.
Possible	3	The accident may occur if additional factors precipitate it, but it is unlikely to happen without them.
Highly likely	4	Will happen more often than not. Additional factors could precipitate an incident but it is still likely to happen without this additional factor.
Inevitable	5	If the work continues as it is, there is almost 100% certainty that an accident will happen, for example: A broken stair or broken rung on a ladder Bare, exposed electrical conductors Unstable stacks of heavy boxes

Risk Rating Score	Definition	Action
1 to 4	Low	No action required
5 to 9	Moderate	Reduce risks if reasonably practicable
10 to 15	High Risk	Priority action to be undertaken
16 to 25	Unacceptable	Action must be taken IMMEDIATELY