Phone
Daily 9:00–21:00 (Beijing Time)
Customer support
Free feature customization — we welcome your suggestions
WeChat
Scan or long-press the QR code to add us
WeChat ID
lrlgem
Email
Feature questions, bug reports, partnerships
FAQ
Frequently Asked Questions
Does the app require an internet connection?
No. LatheCalc Pro runs fully offline. Standard data and calculation engines are built into the app. No registration or login required.
Is my calculation data uploaded?
No. All inputs, history, and favorites are stored locally on your device only. We do not collect or upload any process data.
Can I use the results directly for machining?
This app provides calculation and standard lookup assistance only. It does not replace drawings, process documents, machine manuals, or on-site measurements. Always verify coordinates, units, tool offsets, and machine limits before running a program.
How do I switch language or metric/imperial units?
Go to the Settings tab at the bottom of the app. Under Language and Units & Coordinates, you can adjust UI language, default unit system, and X diameter/radius mode.
How do I restore a previous calculation?
Each completed calculation is saved to the History tab automatically. Tap a record to reuse inputs. You can also star favorite tools and modes on the calculation or tangency template pages.
What should I include when reporting a bug?
Please provide: device model and iOS version, app version, steps to reproduce, expected vs actual result. Screenshots help us diagnose issues faster.
Response time: We typically reply to emails within . For urgent issues, call us; outside business hours, leave a message and we'll call back as soon as we can.