Stitch Sprint Help › Production
Safety check and the DST doctor
The safety check
Every DST is checked after it is written, by reading the actual file back from disk. A file that fails goes to rejected in the saved designs folder, so it can't get mixed in by accident. Save DST is disabled in the app while a check fails.
The result is one of three:
| Verdict | Colour | Meaning |
|---|---|---|
| PASS | green, tick | Within every limit |
| WARN | amber, ! | Look before sewing; it may sew fine |
| FAIL | red, cross | Not safe to send to the machine |
Limits
| Check | Warn | Fail |
|---|---|---|
| Stitch length | longest over 10 mm (snag risk) | any move over 12.1 mm on one axis (DST can't encode it) |
| Short stitches | more than 10% under 0.3 mm (thread breaks) | |
| Peak density (2 mm cells) | over 16 needle penetrations per mm² | over 25 per mm² (needle break, bird nest) |
| Jump with no trim | over 25 mm | |
| Design size | larger than the machine's sewing field | |
| Colour stops | more than the needles | |
| Empty file | no stitches |
Run time in the report is stitches ÷ the machine's speed, plus 4 s per trim and 6 s per colour change.
Trims are encoded as 3 jumps. The move after a trim or a colour change is not counted as a long stitch (since v0.21).
Where the limits came from
Measured from 386 production DSTs that sew well: library median stitch 2.3 mm, 99% under 6.7 mm; peak density p90 11.8, p98 16.3, max 23.5 per mm². Of those 386 known-good files the check passes 358, warns on 28 (19 with stitches over 10 mm, 7 with a dense spot, 2 with more colours than needles, 1 with a jump that has no trim; one file has two of these) and fails none. The doctor brings 19 of the 28 to a pass.
Checking any file
- In the app: the Check a DST tab (DST, PES, PEC, EXP, JEF, VP3, XXX, U01, TBF, SEW, HUS, EMD). Add to a design then places it in a design.
Places to check
Every design lists places worth a look before sewing, under Places to check, and rings them on the hoop. Each ring has a label with its number and a few words, such as "1 · Too thin to sew: left out" or "2 · Narrow opening". Point at a label for the whole note; click it to find its line in the list. Pointing at a line in the list lights its ring. The ring is drawn round the whole shape it is about, so a ring as big as the design means the shape is that big (a hairline outline round a logo, say). The labels:
- Too thin to sew: left out: a shape under 1 mm² or thinner than 0.4 mm, too small for a needle, so it isn't sewn. Make it thicker in the artwork if it should sew;
- Narrow opening: a letter opening or gap narrower than 0.8 mm, which may fill in when sewn;
- Dense spot: the densest spot, when it is over the library's usual peak;
- Long stitch: a stitch long enough to snag.
These are not failures. They are where to look on the preview and on the test sew.
The DST doctor
When a file warns or fails, Check a DST shows a Fix it box if there is something it can fix.
| The check says | The fix |
|---|---|
| A stitch longer than 10 mm | Split into equal parts of 10 mm or less. Across a satin column the new needle points alternate between two lines, so they don't form a ridge |
| A jump over 25 mm with no trim (thread dragged across) | A tie-off, a trim and a tie-in |
| More than 10% of stitches under 0.3 mm | Needle points closer than 0.3 mm to the one before are merged; ties at the start and end of each run stay |
- Fix what the check found shows the fixed copy with its own check. Show the file as it came switches back to compare.
- Save fixed DST saves
NAME fixed.DSTin the saved designs folder, with its preview, report (listing the fixes) and worksheet. The file you loaded is never changed. Add to a design places the fixed copy. - A fix is made only where its check fails, and is not kept if it would change the colour stops or the size.
- Not fixed, and it says so: a design larger than the field, more colour stops than needles, and a spot that is too dense (it doesn't thin stitches out).
- PES, EXP, JEF, VP3 and XXX files can be fixed too; the fixed copy is a DST.
- A whole folder: see Library.
Sew a test of a fixed copy before running it.