Heidenhain repair · Chicago and Illinois
Heidenhain TNC control and scale repair in Illinois
Heidenhain controls run precision 5-axis machines, and Heidenhain scales and encoders measure position on machines from almost every builder. When a Heidenhain part complains, accuracy is usually on the line.
- Fastest response available
- Chicago-based
- Stocked repair vans
- Fanuc & Siemens
Fastest response available
Heidenhain machine down?
Tell us the Heidenhain model, the control and the alarm. The nearest tech with a stocked van takes the call.
- Talk straight to a tech, not a call center
- The nearest stocked van gets the job
- Fanuc and Siemens controls, and most of the shop floor
Quick answerLocalSpindle troubleshoots Heidenhain equipment on site across Chicago and Illinois: TNC 640, TNC 620, iTNC 530, TNC 426 and 430 controls, Heidenhain linear scales and rotary encoders, and DROs. Encoder and scale alarms, contamination, cabling, drive faults and data backups. Call 773-962-0269.
Heidenhain repair in Illinois
TNC controls and the scales that measure everything
Heidenhain, based in Traunreut, Germany, makes two things that matter on Illinois shop floors: TNC controls and precision measurement. Its TNC controls, from older TNC 355, 407 and 426 systems through the TNC 430, 530, 620, 640 and the newest TNC7, run many European five-axis and vertical machining centers, including DMG, Hermle, Chiron and others, plus retrofits on older American machines. Its linear scales, rotary encoders and touch probes show up on machines from many builders, including machines that don’t have a Heidenhain control.
LocalSpindle techs work on both. We troubleshoot TNC controls and their inverters and motors, and we diagnose and repair the scale and encoder problems that cause position and accuracy alarms on machines of every kind.
Linear scales and why they fail
A linear scale measures the actual position of an axis, independent of the ballscrew and motor encoder. That’s why machines with scales can hold accuracy so well. But a scale is a precision glass or steel tape inside a sealed housing, and it can fail when coolant, oil mist, chips or moisture get inside, when the sealing lips wear out, when the air purge isn’t working, when the reading head is damaged in a crash, or when the cable is pinched or soaked.
Scale problems usually show up as position errors, signal amplitude or contamination alarms, or axes that drift or jump. We check the signals, inspect and clean scales where that’s possible, check the air purge and seals, replace damaged reading heads or cables, and help you decide when a scale needs replacement.
TNC controls and inverters
Older TNC controls, like the 355, 407 and 426, are still running on many machines and have aging power supplies, displays, hard drives and batteries. The TNC 430 and 530 were common on 2000s machines and use Heidenhain inverters, with power and axis modules similar to other modular drive systems. The TNC 620 and 640 are common on newer machines.
We back up TNC controls before working on them, including machine parameters, PLC data and programs. Inverter faults often come from motors, encoders, cables or cooling problems, so we test those first. When a module needs replacement, we match it to the system.
Probes and measurement
Heidenhain touch probes and tool setters are used for part setup, measurement and tool measurement. When a probe misfires or gives inconsistent results, it can be the probe, its battery, its receiver, the stylus, the cable or the control settings. We troubleshoot all of them.
Measurement first
Most Heidenhain calls are really about feedback
Heidenhain is best known for measurement: glass linear scales and rotary encoders that tell the control exactly where an axis is. Those parts are very reliable when they’re sealed and dry, and very unhappy when coolant mist, chips or a crushed cable gets in.
A scale alarm, a position error or a part that’s suddenly off in one axis often traces to contamination in the scale, a damaged reading head or a bad connector. We check air purge, seals and cables before condemning the scale itself.
On the control side, the iTNC 530 and TNC 640 are common on Hermle, DMG and other European 5-axis machines. We back them up, read their logs and troubleshoot their drives.
Common calls
Heidenhain problems we see
| Problem | Usual cause |
|---|---|
| Scale or encoder signal amplitude too small | Contamination in the scale, a damaged reading head, or a cable problem |
| Position error on one axis | Feedback problem, a coupling, or a mechanical issue the scale is honestly reporting |
| Control won’t boot or hangs | Hard drive or flash failure, power supply, or corrupt data |
| Axis following error | Mechanics, drive, or feedback |
| DRO counts wrong or jumps | Dirty scale, loose reading head, damaged cable |
On site
What a Heidenhain visit covers
- Back up control data and machine parameters
- Check scale air purge, seals and wipers
- Inspect reading heads and cables
- Check encoder signals
- Troubleshoot drives and motors
- Clean or coordinate repair of contaminated scales
Why scales get dirty
Keeping linear scales clean and dry
Most Heidenhain linear scales are sealed and designed to be fed with clean, dry purge air. When the purge air is missing, wet or oily, coolant mist gets past the seals and coats the glass. The control then sees weak or noisy signals, and the axis alarms or drifts.
We check the purge air supply, its filter and dryer, and the seals along the scale. Fixing the air supply is often what keeps the scale clean afterward.
Rotary encoders on spindles and rotary tables have the same weak spots: connectors and cables exposed to coolant and chips.
Controls
Heidenhain controls we work on
| Control | Common on | Typical calls |
|---|---|---|
| TNC 640 | Current 5-axis machines | Data backup, encoder and drive faults |
| TNC 620 | Mid-range machines | Same as above, simpler setups |
| iTNC 530 | 2000s and 2010s 5-axis machines | Hard drive and boot issues, drives, encoders |
| TNC 426 / 430 | 1990s machines | Aging hardware, data backup, power supplies |
| DROs (ND, POSITIP) | Manual mills and lathes | Scale and cable problems |
Sometimes it can be cleaned and resealed. When the glass or reading head is damaged, we coordinate a repair or replacement.
No. We’re an independent Chicago-based repair company.
Usually because purge air is missing or wet. We check the air supply and the scale seals.
Keep reading
Services for Heidenhain equipment
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Machine down?
Get your Heidenhain back to cutting
Call with the Heidenhain model, the alarm and what it was doing. The nearest tech with a stocked van takes it from there.
CNC machine repair, preventive maintenance and machine sales for machine shops and manufacturers across Illinois. Based in Chicago, with techs and stocked repair vans around the state.
Call: 773-962-0269
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Chicago, Illinois · 773-962-0269