Table of Contents
Colchester Bantam Mk1 Lathe
Specs
| Model | Condor 20 |
| Chuck mounting | D1-3 camlock |
| Spindle taper | 4MT |
| Tailstock taper | 3MT |
| Leadscrew | 6mm pitch |
| Toolpost | Dickson T1 |
Accessories
| Photo | Name | Notes | Location |
|---|---|---|---|
 | 3-jaw chuck | Standard for normal work | Mounted on the lathe |
 | 4-jaw chuck | Chuck for oddly-shaped material and/or work requiring accurate concentricity | TBD |
 | Key for 3-jaw chuck | Behind the headstock | |
 | Key for camlock operation | Used to operate the camlock mechanism to mount/unmount chucks | Behind the headstock |
 | Tailstock tools | Various tools that mount in the tailstock | On the chip tray to the right of the lathe bed |
 | Large drill chuck & key | Tailstock tool storage | |
 | Medium drill chuck | Tailstock tool storage | |
 | Small drill chuck & key | Tailstock tool storage | |
 | Keyless drill chuck | Tailstock tool storage | |
 | Live centre | Live centre for supporting long workpieces or turning between centres | Tailstock tool storage |
Risk Assessment (WIP)
Please see linked page for a full risk assessment of the lathe: Bantam lathe risk assessment.
| Hazard | Risk | Mitigation |
|---|---|---|
| Trapping / Pinching | Closing movements between tools, workpieces and other machine parts under power feed can present a trapping hazard. | Machine users are to ensure they are well aware of their environment and other workshop users, and must disengage power feed and make the machine safe if distracted. Before starting the machine, users should ensure that both the power feed & threading lead screw are disengaged |
| Flying parts | Workpieces (and chuck keys or tools) can be ejected violently if not held correctly | The lathe should not be started until the user has confirmed the workpiece and tool is properly secured, the chuck key is removed, and the work area / machine ways are completely clear. The headstock should not be used to store parts / tools as these can fall into the spinning machinery. Self-ejecting/spring-loaded chuck keys are advised. |
| User injury | Contact with rotating parts and hot swarf can cause cuts, abrasions and burns. | Appropriate feeds and speeds should be selected to minimise stringy chips/“birdnesting”. Users should not attempt to clear chips with the machine running. Metal chips should not be handled directly: use pliers to clear nested chips, a brush to clear loose chips, and heavy gloves should be worn when clearing the chip tray by hand. NB: Gloves should not be worn whilst the machine is in operation - see below. Eye protection must be worn. |
| Entanglement | Long hair, dangling jewellery, loose clothing or gloves can become entangled with rotating parts, dragging the user onto them. Application of cutting oil using a brush presents an entanglement risk. | Loose clothing should not be worn, or should be covered with an appropriately secured apron. Long hair is to be tied back. Loose jewellery should be removed. Gloves should not be worn when the machine is in operation. |
| Lack of space/pushing by others | Limited space can cause the user of the lathe to be pushed by other people in the space. | Area surrounding the lathe should be closed of when in use. |
| Slips and trips | Spilled cutting oil can make the area around the machine slippery. | Appropriate footwear should be worn. Prompt removal of spilled cutting oil. |
| Electrical hazards | Electrical shock due to damaged wiring. | Regular PAT testing. Inspection of cables prior to use. |
| Fire | Hot flying metal pieces igniting surrounding flammable material. | Ensure surrounding area is clear of flammable material. Particular attention must be paid to nearby sawdust accumulation. Fire extinguishers are available in the vicinity of the machine. |
| Lone Working |
Temporary list of hazards / machine health concerns
- Entanglement with the spindle, chuck, workpiece or feed mechanism.
- Being pushed in by other users due to lack of space.
- Unsecured spinning things flying off - chuck key, loose work, things falling from the headstock onto the chuck.
- Sharp/hot metal chips.
- Entanglement in the belts/gearing behind the cover.
- Collisions between chuck/workpiece & toolholder/cross-slide/tool.
- Taking overly-heavy cuts and stalling the machine or breaking something.
- Collisions due to power-feed/threading.
- Damage to VFD from E-Stop overuse.
- Damage to lathe gearing from starting the lathe out of gear, or adjusting gears during running.
- Loose tool/toolholder/slides being pulled into workpiece.
- Unintended use of power-feed/threading at startup.
- Obstruction of brake lever.
- Misconfiguration of VFD.
- Oil or items on the floor causing slipping/tripping.
- Burns - Hot tools / workpiece
- Fire - hot oil / work / use of solvents (e.g. for marking) / machining plastics
- Fumes - melting plastic workpieces
- Oil spray - e.g. getting in eyes
- Electric shock (if cables are damaged)
- Lone working / how to get help
Motor
Original
The motor was replaced around the end of November 2025. The old motor (probably original) had wildly different winding resistances, possibly because it spent its life miswired. It was probably a Dahlander wound motor, which had two of the centre taps connected, but not the other one. This was in accordance with the lathe manual, which Mike and River recon was wrong. It was rated 1.5 kW, and could be wired as either 2 or 4 pole.
Elektrim, new Nov 2025
The new motor is an Elektrim 1.1kW, 2 pole model. It is installed in delta configuration, at which it is rated at 220-240V.
New motor tests, before installation.
Coils all 6.06 ohm.
IRs
Tested at 1kV.
Windings to earth: All 21 G Ohm after about 15 secs.
Inter-winding resistance:
- UV > 53 M
- UW > 53 M
- VW > 63 M
Read after a short wait. Was still climbing.
VFD
The motor is driven by an HY02D223B VFD. This was also installed end Nov 2025 after the previous one died with an explosion of sparks. It outputs ~230V phase-phase.
There is a partial wiring diagram on paper in the drawer under the lathe.
Configuration
- PD001 1 source of commands: terminals
- PD003 Frequency run at when using onboard digital control.
- PD004 Set to motor nameplate frequency, i.e. 50 Hz. The default is 400, not 50 as the manual says.
- PD005 Max frequency: Set 50 Hz.
- PD007 Min frequency. Leave at default, I think.
- PD011 Frequency lower limit, to avoid knob setting it too slow: 40.
- PD014 Accel time: 2
- PD015 Decel time: 2
- PD026 Stop mode: 0 for decel, 1 coast. Left on default 0 for now. Maybe should add breaking resistor and try that.
- PD027 and 028: 10 Hz seems to work.
- Start, reverse, stop buttons config:
- PD044: 2
- PD045: 3
- PD046: 4
- PD141 Rated motor voltage 240
- PD142 Rated motor current: 4.3
- PD143 Motor pole number (count): 2
- PD144 Rated motor revs: 2760
See page 37 of VFD manual for more info and wiring diagram.
PAT
2025-11-25, with new VFD and motor.
PAT tester says:
- 0.05 Ohm earth continuity to lathe body.
- IR < 19.99 M Ohm
- Substitute leakage test: 1.3 mA
I expect a fairly large leakage because of filter capacitors. Also note the “substitute leakage” test is considered somewhat sus in general. I recon this result is acceptable.
IET PAT testing Code of Practice 5th ed. gives leakage limit of 5mA. Note Hacklab PAT tester has a lower fail limit of (probably) 0.75mA.
Log
- 2016-10-26 - Lathe delivered
- 2016-10-31 - Spindle oil changed (~3L) & gearbox oil filled (~1.5L). Gearbox oil was almost empty so may need to monitor/check for wear. The spindle oil was 'Hydraulic oil ISO 32' from Westway Lubricants (sold as an equivalent to Shell Tellus 27).
- 2023-06-29 - Topped up the spindle oil, it had dropped to the bottom edge of the sight glass. There is a slight leak from around the rear spindle bearing, but probably more effort than it's worth to investigate/fix.
- 2024-08-26 - Fitted adjustable screw foot & levelled the bed ways. Measured <10 um taper in 150 mm when cutting a test bar.
- 2024-10-24 - VFD died with a big spark on power on.
- 2025-11-19 New VFD and motor installed.
- 2026-03-29 Topped up spindle and gear oil. Fixed a screw on the brake adjustment that was rubbing on the motor pulley. Fitted a standard set of change gears (bottom picture on the front panel).