The phone's heading reference was reset. Put the phone back on the last recorded station and tap Re-link before you continue.
Recorded sweep
Speed between marks shows a missed or double tap. A missed mark shows about half your usual speed; a double tap shows a very high one. Editing a distance shifts every mark after it by the same amount. Deleting a mark pulls the later marks back by one gap.
How to trace continuously
- Mark the wall face with a tape at even spacing, e.g. every 12", measured along the curve. Set that spacing below.
- Hold the phone screen-up with its long edge pressed flat on the wall, top pointing along the wall. Pick one spot on the phone, like its back corner, to line up with the marks.
- Tap Start sensors, put that spot on the first mark, tap Start sweep and hold still until the beep.
- Slide the phone steadily, about a foot every two seconds, keeping the edge on the wall. Each time your spot passes a mark, tap the big Mark button with your other hand.
- Tap Stop as the spot reaches the last mark. If you stopped somewhere else, fix the stop distance in the sweep table.
- Optional: put the phone back on the start mark and tap Close check at start to take out gyro drift.
How to trace a wall
- Mark stations along the wall face with a tape, e.g. every 12". Measure along the face, following the curve.
- Hold the phone screen-up with its long edge pressed flat on the wall, top of the phone pointing along the wall. Keep the same edge on the wall and the top pointing the same way at every station.
- Tap Start sensors. Put the phone on station 0, let the chip turn to Steady, then tap Record. Wait for the beep before you move it.
- Move to each mark and record. If a mark isn't at the default spacing, change the distance before you record.
- When you're done, go back to station 0 and tap Close check. This measures gyro drift so it can be taken out of the trace.
- On Results, enter a taped chord from first to last station to check or correct the trace.
Trace so far
Recorded stations
Offsets from a string line
Use this when sensors aren't available, or as an independent check. Stretch a string past both ends of the curve, on equal blocks if the face bulges toward you. Measure square from the string to the wall face at each point along the string.
Shape from offsets
Plan
Deviation from design arc
+ means the face is outside the arc (farther from its center), − means inside. The shaded band is your tolerance.
Tape check
Export to AutoCAD
DXF in inches. Station 0 is at 0,0 and the chord runs along +X. Layers: TRACE polyline, FIT_ARC, DESIGN_ARC, STATIONS with deviation labels, CENTER, NOTES.
Stations
Job
Design and tolerance
Data
Your trace is kept in this browser on this device only. Export a DXF to keep a copy.