MINEXPLODE breaks a MINSERT — a block inserted as a rectangular array in one object — into the separate block references it stands for.
What MinExplode does
AutoCAD will not do this. EXPLODE refuses a MINSERT outright, and always has. So a drawing that arrived with its grid of columns, its car parking bays or its ceiling tiles as one MINSERT cannot be edited a bay at a time without redrawing the lot.
How to use it
- Load the routine with
APPLOAD, or put it on your support file search path. - Type
MINEXPLODE. - Pick the MINSERT.
- It becomes separate block references you can edit individually.
How it works
A MINSERT is an ordinary INSERT with four extra numbers on it: how many columns (group 70), how many rows (71), and the spacing of each (44 and 45).
Set all four back to zero and the object stops being a MINSERT and becomes a plain block reference at the first position. Then ARRAY rebuilds the rest as real, separate insertions.
The rotation matters here. A MINSERT’s array runs along the block’s own rotation rather than along the drawing’s X axis, so SNAPANG is set to the block’s angle for the duration — that is what ARRAY measures its rows and columns against — and put back afterwards. Miss that and a rotated MINSERT explodes into an array running the wrong way.
The whole thing is one undo group, which is not cosmetic. Between converting the object and finishing the array there is a moment where a single block reference stands where the whole array was, with the other positions simply gone. Interrupted there without an undo group, the way back is several separate U presses and some guessing.
Notes and limits
- SNAPANG is restored on every path, so an interrupted run does not leave your crosshairs rotated.
- Rotated MINSERTs work.
- The result is separate block references, not exploded geometry — the blocks are still blocks.
- One undo group covers the conversion and the array together.
Download and details
| Name | MinExplode — break a MINSERT into separate block references |
| Download | MinExplode.lsp — 5.6 KB, plain AutoLISP source. Downloads directly; no zip to unpack. |
| Type | AutoCAD AutoLISP routine |
| Command | MINEXPLODE |
| Requires | nothing beyond a CAD platform with AutoLISP. |
| Source size | 5.6 KB, 130 lines |
| Error handling | Yes — a *error* handler restores every system variable it changed, on cancel as well as on error. |
| Undo | The whole operation is wrapped in a single undo group, so one U reverses all of it. |
| Compatibility | AutoCAD (any release with AutoLISP), BricsCAD, ZWCAD, GstarCAD, ProgeCAD and other IntelliCAD-based platforms. AutoCAD LT needs a LISP enabler. No .NET, no ObjectARX, no installer. |
| Author | YZ, August 2026 |
| Licence | Free to use, supplied “as is” with no warranty. |
References
- Anonymous blocks in AutoCAD — the other block type that behaves oddly
- BLOCKPROMOTE LISP — pulling a nested block out to the top level
- SMARTBURST LISP — exploding blocks and keeping the attribute values
- More free AutoLISP routines on this site
- Wisey’s Steel Shapes — free structural steel section drawing program