diff --git a/src/Mod/Fem/femsolver/mystran/add_con_fixed.py b/src/Mod/Fem/femsolver/mystran/add_con_fixed.py
index 81be959d58..605c330d39 100644
--- a/src/Mod/Fem/femsolver/mystran/add_con_fixed.py
+++ b/src/Mod/Fem/femsolver/mystran/add_con_fixed.py
@@ -35,7 +35,7 @@ def add_con_fixed(f, model, mystran_writer):
     # spc1 card
     spc_ids = []
     fixed_code = "# spc1 card, Defines a set of single-point constraints\n"
-    for i, femobj in enumerate(mystran_writer.fixed_objects):
+    for i, femobj in enumerate(mystran_writer.member.cons_fixed):
 
         conid = i + 2  # 1 will be the conid of the spcadd card
         spc_ids.append(conid)
diff --git a/src/Mod/Fem/femsolver/mystran/add_con_force.py b/src/Mod/Fem/femsolver/mystran/add_con_force.py
index db40356c04..152d7572cc 100644
--- a/src/Mod/Fem/femsolver/mystran/add_con_force.py
+++ b/src/Mod/Fem/femsolver/mystran/add_con_force.py
@@ -36,7 +36,7 @@ def add_con_force(f, model, mystran_writer):
     scale_factors = []
     load_ids = []
     force_code = "# force cards, mesh node loads\n"
-    for i, femobj in enumerate(mystran_writer.force_objects):
+    for i, femobj in enumerate(mystran_writer.member.cons_force):
 
         sid = i + 2  # 1 will be the id of the load card
         scale_factors.append(1.0)
diff --git a/src/Mod/Fem/femsolver/z88/writer.py b/src/Mod/Fem/femsolver/z88/writer.py
index 21412d4b25..1824e26c88 100644
--- a/src/Mod/Fem/femsolver/z88/writer.py
+++ b/src/Mod/Fem/femsolver/z88/writer.py
@@ -143,7 +143,7 @@ class FemInputWriterZ88(writerbase.FemInputWriter):
 
         # fixed constraints
         # write nodes to constraints_data (different from writing to file in ccxInpWriter
-        for femobj in self.fixed_objects:
+        for femobj in self.member.cons_fixed:
             for n in femobj["Nodes"]:
                 constraints_data.append((n, "{}  1  2  0\n".format(n)))
                 constraints_data.append((n, "{}  2  2  0\n".format(n)))
@@ -152,7 +152,7 @@ class FemInputWriterZ88(writerbase.FemInputWriter):
         # forces constraints
         # write node loads to constraints_data
         # a bit different from writing to file for ccxInpWriter
-        for femobj in self.force_objects:
+        for femobj in self.member.cons_force:
             # femobj --> dict, FreeCAD document object is femobj["Object"]
             direction_vec = femobj["Object"].DirectionVector
             for ref_shape in femobj["NodeLoadTable"]:
@@ -187,7 +187,7 @@ class FemInputWriterZ88(writerbase.FemInputWriter):
 
     # ********************************************************************************************
     def write_z88_materials(self):
-        mat_obj = self.material_objects[0]["Object"]
+        mat_obj = self.member.mats_linear[0]["Object"]
         material_data_file_name = "51.txt"
         materials_file_path = self.file_name + "mat.txt"
         fms = open(materials_file_path, "w")
@@ -209,7 +209,7 @@ class FemInputWriterZ88(writerbase.FemInputWriter):
         element_properties_file_path = self.file_name + "elp.txt"
         elements_data = []
         if meshtools.is_edge_femmesh(self.femmesh):
-            beam_obj = self.beamsection_objects[0]["Object"]
+            beam_obj = self.member.geos_beamsection[0]["Object"]
             area = 0
             if beam_obj.SectionType == "Rectangular":
                 width = beam_obj.RectWidth.getValueAs("mm").Value
@@ -236,7 +236,7 @@ class FemInputWriterZ88(writerbase.FemInputWriter):
                 "Be aware, only trusses are supported for edge meshes!\n"
             )
         elif meshtools.is_face_femmesh(self.femmesh):
-            thick_obj = self.shellthickness_objects[0]["Object"]
+            thick_obj = self.member.geos_shellthickness[0]["Object"]
             thickness = thick_obj.Thickness.getValueAs("mm").Value
             elements_data.append(
                 "1 {} {} 0 0 0 0 0 0 "