Segment references
Ordinarily a punch's Y position is machine-referenced: an offset from the machine's center or edge. That works, and it stays the default — a punch with no segment behaves exactly as it always has, and nothing on this page is required to punch parts.
Machine references have one weakness: they describe the machine, not the part. Consider a purlin (C or Z profile) with unequal flanges. The center of the web no longer lines up with the center of the machine, so a hole that belongs "in the middle of the web" needs a different hand-computed offset for every profile size — and a design system that knows the part can't express the hole without also knowing the machine.
A segment reference describes the position the way the part drawing does: name a segment of the formed profile and give an offset within it.
"1.063 into the left flange, measured from the web."
Eclipse converts that to machine coordinates when it solves the pattern for a specific machine, using that machine's tooling dimensions. Two things follow:
- Family portability. X references already make patterns length-parametric; segment references make them profile-parametric. One pattern can serve an entire purlin family — the flange hole lands correctly on every size.
- Design-system friendliness. External software can submit patterns that describe the finished part without knowing anything about machine geometry. See Punch pattern import.
Segment references are valid only on shape punches. On tool or macro punches a segment is rejected as a validation error, not silently ignored.
The segments
Eclipse recognizes three segment names, resolved from the tooling dimensions already configured per machine:
lip │ FlangeMinus │ Web │ FlangePlus │ lip
────┼─────────────┼───────┬───────┼────────────┼────
│
web center
| Segment | The part of the profile | Geometry source (tooling dimensions) |
|---|---|---|
Web | The flat web between the two flange bends | Fin Width |
FlangePlus | The flange on the machine's plus side | Leg Height |
FlangeMinus | The flange on the machine's minus side | Leg Height 2 |
These dimensions live on the machine's tooling entry (see the tooling detail page). If Leg Height 2 is zero or blank, the profile is treated as symmetric — both flanges use Leg Height. That matches how legacy machines were configured, so existing tooling entries keep working.
Lips (the short return at a flange tip) are not a segment — a hole in the lip cannot be expressed with segment references today.
External design software rarely uses these exact names — it says Flange Left, W, or
whatever its own vocabulary is. The alias table maps vendor names
onto these canonical segments per machine.
Anchors: where the offset measures from
Within a segment, the offset measures from an anchor. Each segment has a natural default:
| Segment | Default anchor | Offset direction |
|---|---|---|
Web | The web center | Signed — positive/negative across the web |
FlangePlus / FlangeMinus | The inner bend (where the flange meets the web) | Positive toward the flange tip, away from the web |
A punch that gives just a segment and an offset uses the default anchor — this is all an external system ever needs to send.
In the pattern editor you can also anchor explicitly, using the punch's Y reference. When a segment is set, the Y reference choices change meaning — they select an anchor within the segment instead of a machine reference:
| Y-Reference | Meaning under a segment |
|---|---|
| Default | The segment's default anchor, as above — or the anchor configured for the vendor's alias entry |
| Center+ / Center- | The segment's center, offset toward machine plus / minus |
| +Edge / -Edge | The segment's plus / minus boundary, measuring into the segment. On a flange, one boundary is the inner bend and the other the outer bend; on the web they are the two web/flange bends. |
The Macro+ / Macro- references are not offered under a segment (a macro reference on a segment punch is a validation error). The mirror variants remain available: as everywhere else they expand into the +/− pair when the pattern is saved — here straddling the segment's center or inset from its two boundaries.
The edge anchors are what keep a hole like "0.75 from the lip side of the flange" parametric:
without them it becomes flange width − 0.75, baking a dimension into the pattern and breaking
family portability.
The segment alias table
Every design system has its own segment vocabulary and conventions: Flange Left vs.
FlangeMinus, which direction across the web is positive, which tooling column holds which
flange's height. The Segment Aliases table — configured per machine, on the Segments
tab of the machine's Shape Table editor — carries those facts, so patterns keep the vendor's
own names.
Each entry maps:
| Column | Meaning |
|---|---|
| Alias | The name as the vendor sends it: Flange Left, W, … (20 characters max) |
| Segment | The canonical segment it lands on: Web, FlangePlus, FlangeMinus |
| Default Anchor | The anchor the vendor measures from when the punch doesn't say. For Web entries, choosing Center+ vs. Center- also binds which direction the vendor considers positive. |
| Leg Height | Which tooling dimension (Leg Height / Leg Height 2) holds this flange's height, when the vendor's convention differs from the machine's default. |
Points worth knowing:
- Patterns keep the vendor's names. The alias is resolved when the pattern is solved, not when it is imported — so correcting a wrong alias entry fixes every existing pattern immediately, without re-importing anything. Edits to the table automatically re-solve the machine's cached solutions.
- Matching is case-insensitive, and the canonical names (
Web,FlangePlus,FlangeMinus) always work without an entry. - Entries describe the vendor's conventions, not the machine — a plant's machines typically carry identical entries.
- The alias vocabulary for a given design system is agreed during commissioning; see Commissioning segment punching.
Mixing
Segment-referenced and machine-referenced punches mix freely within one pattern. Resolution is per punch: rows with a blank segment are untouched and behave exactly as before.
When resolution fails
Segment resolution fails loudly rather than guessing, surfacing as solution alerts on the job — the same place a missing shape shows up:
- Unknown segment name — the punch names a segment that is neither canonical nor an alias on the target machine. Fix the pattern, or add the alias entry.
- Missing profile geometry — the pattern needs segment resolution but the machine's tooling entry has no usable dimensions (Fin Width or Leg Height missing/zero). Fill in the tooling dimensions.
- Missing bend correction — the machine has commissioned corrections, but this job's gauge, side, and bend direction don't resolve to one. Add the tooling's direction rule or commission the missing combination; see when a correction can't be resolved.
- Invalid combination — a segment on a tool/macro punch, or a Macro ± reference under a segment.
The flat view still opens for a failed item and shows which punches resolved and which didn't, which makes these quick to diagnose.
Looking ahead
Today's three segment names are resolved from tooling dimensions. A future phase resolves segment names against full profile drawings from a shared library, allowing any named segment — including lips — with the same pattern format and wire contract.