diff --git a/cura/Machines/Models/CustomQualityProfilesDropDownMenuModel.py b/cura/Machines/Models/CustomQualityProfilesDropDownMenuModel.py
index f2b164703f..0d297379cd 100644
--- a/cura/Machines/Models/CustomQualityProfilesDropDownMenuModel.py
+++ b/cura/Machines/Models/CustomQualityProfilesDropDownMenuModel.py
@@ -1,7 +1,6 @@
 # Copyright (c) 2018 Ultimaker B.V.
 # Cura is released under the terms of the LGPLv3 or higher.
 
-from UM.Application import Application
 from UM.Logger import Logger
 
 from cura.Machines.Models.QualityProfilesDropDownMenuModel import QualityProfilesDropDownMenuModel
@@ -15,7 +14,7 @@ class CustomQualityProfilesDropDownMenuModel(QualityProfilesDropDownMenuModel):
     def _update(self):
         Logger.log("d", "Updating %s ...", self.__class__.__name__)
 
-        active_global_stack = Application.getInstance().getMachineManager().activeMachine
+        active_global_stack = self._machine_manager.activeMachine
         if active_global_stack is None:
             self.setItems([])
             Logger.log("d", "No active GlobalStack, set %s as empty.", self.__class__.__name__)
diff --git a/cura/Machines/Models/QualityManagementModel.py b/cura/Machines/Models/QualityManagementModel.py
index ab0101cfc6..a3c321815a 100644
--- a/cura/Machines/Models/QualityManagementModel.py
+++ b/cura/Machines/Models/QualityManagementModel.py
@@ -27,7 +27,7 @@ class QualityManagementModel(ListModel):
         self._container_registry = CuraApplication.getInstance().getContainerRegistry()
         self._machine_manager = CuraApplication.getInstance().getMachineManager()
         self._extruder_manager = CuraApplication.getInstance().getExtruderManager()
-        self._quality_manager = CuraApplication.getInstance()._quality_manager
+        self._quality_manager = CuraApplication.getInstance().getQualityManager()
 
         self._machine_manager.globalContainerChanged.connect(self._update)
         self._quality_manager.qualitiesUpdated.connect(self._update)
@@ -35,7 +35,7 @@ class QualityManagementModel(ListModel):
         self._update()
 
     def _update(self):
-        global_stack = self._machine_manager._global_container_stack
+        global_stack = self._machine_manager.activeMachine
 
         quality_group_dict = self._quality_manager.getQualityGroups(global_stack)
         quality_changes_group_dict = self._quality_manager.getQualityChangesGroups(global_stack)
diff --git a/cura/Machines/Models/QualityProfilesDropDownMenuModel.py b/cura/Machines/Models/QualityProfilesDropDownMenuModel.py
index 30b8634294..9e38184ce7 100644
--- a/cura/Machines/Models/QualityProfilesDropDownMenuModel.py
+++ b/cura/Machines/Models/QualityProfilesDropDownMenuModel.py
@@ -33,11 +33,13 @@ class QualityProfilesDropDownMenuModel(ListModel):
         self.addRoleName(self.QualityGroupRole, "quality_group")
         self.addRoleName(self.QualityChangesGroupRole, "quality_changes_group")
 
-        # connect signals
-        Application.getInstance().globalContainerStackChanged.connect(self._update)
-        Application.getInstance().getMachineManager().activeQualityGroupChanged.connect(self._update)
+        self._application = Application.getInstance()
+        self._machine_manager = self._application.getMachineManager()
+        self._quality_manager = Application.getInstance().getQualityManager()
 
-        self._quality_manager = Application.getInstance()._quality_manager
+        # connect signals
+        self._application.globalContainerStackChanged.connect(self._update)
+        self._machine_manager.activeQualityGroupChanged.connect(self._update)
         self._quality_manager.qualitiesUpdated.connect(self._update)
 
         self._layer_height_unit = ""  # This is cached
@@ -47,15 +49,14 @@ class QualityProfilesDropDownMenuModel(ListModel):
     def _update(self):
         Logger.log("d", "Updating quality profile model ...")
 
-        machine_manager = Application.getInstance().getMachineManager()
-        global_stack = machine_manager._global_container_stack
+        global_stack = self._machine_manager.activeMachine
         if global_stack is None:
             self.setItems([])
             Logger.log("d", "No active GlobalStack, set quality profile model as empty.")
             return
 
         # Check for material compatibility
-        if not machine_manager.activeMaterialsCompatible():
+        if not self._machine_manager.activeMaterialsCompatible():
             self.setItems([])
             return
 
@@ -82,7 +83,7 @@ class QualityProfilesDropDownMenuModel(ListModel):
         self.setItems(item_list)
 
     def _fetchLayerHeight(self, quality_group: "QualityGroup"):
-        global_stack = Application.getInstance().getMachineManager()._global_container_stack
+        global_stack = self._machine_manager.activeMachine
         if not self._layer_height_unit:
             unit = global_stack.definition.getProperty("layer_height", "unit")
             if not unit:
diff --git a/cura/Machines/Models/QualitySettingsModel.py b/cura/Machines/Models/QualitySettingsModel.py
index a62654ad2c..9e18261d32 100644
--- a/cura/Machines/Models/QualitySettingsModel.py
+++ b/cura/Machines/Models/QualitySettingsModel.py
@@ -33,7 +33,7 @@ class QualitySettingsModel(ListModel):
 
         self._container_registry = ContainerRegistry.getInstance()
         self._application = Application.getInstance()
-        self._quality_manager = self._application._quality_manager
+        self._quality_manager = self._application.getQualityManager()
 
         self._extruder_position = ""
         self._selected_quality_item = None  # The selected quality in the quality management page
@@ -73,7 +73,7 @@ class QualitySettingsModel(ListModel):
 
         items = []
 
-        global_container_stack = Application.getInstance().getGlobalContainerStack()
+        global_container_stack = self._application.getGlobalContainerStack()
         definition_container = global_container_stack.definition
 
         quality_group = self._selected_quality_item["quality_group"]