CalculiX (official versions are on www.calculix.de, the official GitHub repository is at https://github.com/Dhondtguido/CalculiX).

Topic	Replies	Views	Activity
CalculiX User Meeting 2026 Official announcements Dear CalculiX users, We are pleased to announce the first CalculiX User Meeting, hosted by MTU Aero Engines in Munich. The meeting is aimed at professional CalculiX users and has the following objectives: Learning ab…	5	955	October 19, 2026
Welcome to Discourse Uncategorized	0	3613	July 28, 2020
Installation of CCX_2.23 fun Getting started	16	502	October 21, 2026
Abq2ccx input converter (Abaqus to CalculiX) Tool interfaces	17	496	October 21, 2026
T3D3 Flapping midside node Analysis issues	16	48	October 21, 2026
CalculiX and LIS solver Code development	7	193	October 20, 2026
CalculiX 2.23 binaries for Windows 11 x64 Uncategorized	0	52	October 19, 2026
USER element : 1D beam custom implementation Code development	55	1571	October 19, 2026
ABAQUSNL user materials: umat_abaqusnl.f never sets U0, so the STRESS passed to the UMAT is undefined Analysis issues	4	58	October 19, 2026
*BOUNDARY on DOF 8 in a structural model silently fixes the rotation about x (DOF 4) instead of giving an error Analysis issues	3	42	October 19, 2026
Element deletion by *DAMAGE INITIATION stops the run when nodes are left without elements (singular matrix, exit 255, no message; segfault if no element is left) Analysis issues	3	38	October 19, 2026
Linear STATIC step: EL FILE with SDV segfaults when the model has *DEPVAR (xstaten is never allocated in linstatic.c) Analysis issues	2	46	October 19, 2026
*SHELL SECTION, COMPOSITE: a layer without an orientation inherits the previous layer's orientation instead of the section's ORIENTATION or the global axes Analysis issues	2	34	October 19, 2026
ORIENTATION: a DISTRIBUTION name that reads as a number (D1, E1, E5, 12, ...) is taken as zero coordinates, and the run stops with only "matrix found to be singular" Analysis issues	3	37	October 19, 2026
Explicit dynamics: B32/B32R beams with SECTION=CIRC get an unstable increment (element height taken as √2·d), and the run ends in NaN with "Job finished" Analysis issues	2	33	October 19, 2026
Quadratic membranes (M3D6, M3D8, M3D8R) fail the uniaxial patch test, and two M3D8R elements form a mechanism Analysis issues	3	41	October 19, 2026
U1 beam element: nodal forces have wrong signs (axial at node 1, shear at node 2), so RF does not balance the loads Analysis issues	4	39	October 19, 2026
*MPC silently ignores an undefined node set, so a second PLANE/STRAIGHT line in one card joins the first MPC Analysis issues	2	33	October 19, 2026
*EQUATION that names the same DOF in two terms is mis-assembled: wrong stiffness and mass, no message Analysis issues	2	48	October 19, 2026
FreeCAD 26.3 available Tool interfaces	7	211	October 18, 2026
CCX Multi-Solver and CGX-GLFW: CCX+CGX with installer, modern solvers & graphics for Linux/Mac/Win Code development	6	292	October 18, 2026
Collected posts on third party developments, examples, etc Tool interfaces	37	1017	October 17, 2026
Dynamic , Explicit Model setup	27	1661	October 17, 2026
Ccxview: results viewer for CalculiX Postprocessing/Visualization	33	626	October 13, 2026
Weakness of 1st order shell tri elements against other codes Analysis issues	11	475	October 10, 2026
Proposal for official building instructions Getting started	10	312	October 9, 2026
Cyclic symmetry ngraph=2 corrupted results file for restart frequency analysis Analysis issues	2	92	October 9, 2026
Nonlinear Axial Compression (Buckling) of a Cylinder not Converging Analysis issues	104	1864	October 5, 2026
Discord server for PrePoMax / CalculiX and GitHub repo with validation cases Site Feedback	0	115	October 5, 2026
HYPERFOAM Model Issue Analysis issues	59	535	October 2, 2026

CalculiX User Meeting 2026

Dear CalculiX users, We are pleased to announce the first CalculiX User Meeting, hosted by MTU Aero Engines in Munich. The meeting is aimed at professional CalculiX users and has the following objectives: Learning ab…