Index: sansmodels/src/sans/models/c_models/CHollowCylinderModel.cpp
===================================================================
--- sansmodels/src/sans/models/c_models/CHollowCylinderModel.cpp	(revision 870f131f9d526f28fcaa1de9825b193ca97877e6)
+++ sansmodels/src/sans/models/c_models/CHollowCylinderModel.cpp	(revision e2afadff3f4263f27adf3503adb9ffba97b1e122)
@@ -91,6 +91,6 @@
         PyDict_SetItemString(self->params,"length",Py_BuildValue("d",400.000000));
         PyDict_SetItemString(self->params,"axis_phi",Py_BuildValue("d",0.000000));
+        PyDict_SetItemString(self->params,"radius",Py_BuildValue("d",30.000000));
         PyDict_SetItemString(self->params,"background",Py_BuildValue("d",0.010000));
-        PyDict_SetItemString(self->params,"shell_radius",Py_BuildValue("d",30.000000));
         PyDict_SetItemString(self->params,"contrast",Py_BuildValue("d",0.000005));
         // Initialize dispersion / averaging parameter dict
@@ -101,6 +101,6 @@
         PyDict_SetItemString(self->dispersion, "core_radius", disp_dict);
         disp_dict = PyDict_New();
-        self->model->shell_radius.dispersion->accept_as_source(visitor, self->model->shell_radius.dispersion, disp_dict);
-        PyDict_SetItemString(self->dispersion, "shell_radius", disp_dict);
+        self->model->radius.dispersion->accept_as_source(visitor, self->model->radius.dispersion, disp_dict);
+        PyDict_SetItemString(self->dispersion, "radius", disp_dict);
         disp_dict = PyDict_New();
         self->model->length.dispersion->accept_as_source(visitor, self->model->length.dispersion, disp_dict);
@@ -248,6 +248,6 @@
     self->model->length = PyFloat_AsDouble( PyDict_GetItemString(self->params, "length") );
     self->model->axis_phi = PyFloat_AsDouble( PyDict_GetItemString(self->params, "axis_phi") );
+    self->model->radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "radius") );
     self->model->background = PyFloat_AsDouble( PyDict_GetItemString(self->params, "background") );
-    self->model->shell_radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "shell_radius") );
     self->model->contrast = PyFloat_AsDouble( PyDict_GetItemString(self->params, "contrast") );
     // Read in dispersion parameters
@@ -256,6 +256,6 @@
     disp_dict = PyDict_GetItemString(self->dispersion, "core_radius");
     self->model->core_radius.dispersion->accept_as_destination(visitor, self->model->core_radius.dispersion, disp_dict);
-    disp_dict = PyDict_GetItemString(self->dispersion, "shell_radius");
-    self->model->shell_radius.dispersion->accept_as_destination(visitor, self->model->shell_radius.dispersion, disp_dict);
+    disp_dict = PyDict_GetItemString(self->dispersion, "radius");
+    self->model->radius.dispersion->accept_as_destination(visitor, self->model->radius.dispersion, disp_dict);
     disp_dict = PyDict_GetItemString(self->dispersion, "length");
     self->model->length.dispersion->accept_as_destination(visitor, self->model->length.dispersion, disp_dict);
@@ -331,6 +331,6 @@
     self->model->length = PyFloat_AsDouble( PyDict_GetItemString(self->params, "length") );
     self->model->axis_phi = PyFloat_AsDouble( PyDict_GetItemString(self->params, "axis_phi") );
+    self->model->radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "radius") );
     self->model->background = PyFloat_AsDouble( PyDict_GetItemString(self->params, "background") );
-    self->model->shell_radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "shell_radius") );
     self->model->contrast = PyFloat_AsDouble( PyDict_GetItemString(self->params, "contrast") );
     // Read in dispersion parameters
@@ -339,6 +339,6 @@
     disp_dict = PyDict_GetItemString(self->dispersion, "core_radius");
     self->model->core_radius.dispersion->accept_as_destination(visitor, self->model->core_radius.dispersion, disp_dict);
-    disp_dict = PyDict_GetItemString(self->dispersion, "shell_radius");
-    self->model->shell_radius.dispersion->accept_as_destination(visitor, self->model->shell_radius.dispersion, disp_dict);
+    disp_dict = PyDict_GetItemString(self->dispersion, "radius");
+    self->model->radius.dispersion->accept_as_destination(visitor, self->model->radius.dispersion, disp_dict);
     disp_dict = PyDict_GetItemString(self->dispersion, "length");
     self->model->length.dispersion->accept_as_destination(visitor, self->model->length.dispersion, disp_dict);
@@ -403,6 +403,6 @@
     self->model->length = PyFloat_AsDouble( PyDict_GetItemString(self->params, "length") );
     self->model->axis_phi = PyFloat_AsDouble( PyDict_GetItemString(self->params, "axis_phi") );
+    self->model->radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "radius") );
     self->model->background = PyFloat_AsDouble( PyDict_GetItemString(self->params, "background") );
-    self->model->shell_radius = PyFloat_AsDouble( PyDict_GetItemString(self->params, "shell_radius") );
     self->model->contrast = PyFloat_AsDouble( PyDict_GetItemString(self->params, "contrast") );
     // Read in dispersion parameters
@@ -411,6 +411,6 @@
     disp_dict = PyDict_GetItemString(self->dispersion, "core_radius");
     self->model->core_radius.dispersion->accept_as_destination(visitor, self->model->core_radius.dispersion, disp_dict);
-    disp_dict = PyDict_GetItemString(self->dispersion, "shell_radius");
-    self->model->shell_radius.dispersion->accept_as_destination(visitor, self->model->shell_radius.dispersion, disp_dict);
+    disp_dict = PyDict_GetItemString(self->dispersion, "radius");
+    self->model->radius.dispersion->accept_as_destination(visitor, self->model->radius.dispersion, disp_dict);
     disp_dict = PyDict_GetItemString(self->dispersion, "length");
     self->model->length.dispersion->accept_as_destination(visitor, self->model->length.dispersion, disp_dict);
@@ -476,6 +476,6 @@
     if (!strcmp(par_name, "core_radius")) {
         self->model->core_radius.dispersion = dispersion;
-    } else    if (!strcmp(par_name, "shell_radius")) {
-        self->model->shell_radius.dispersion = dispersion;
+    } else    if (!strcmp(par_name, "radius")) {
+        self->model->radius.dispersion = dispersion;
     } else    if (!strcmp(par_name, "length")) {
         self->model->length.dispersion = dispersion;
