diff --git a/src/Mod/Fem/Gui/TaskFemConstraintForce.cpp b/src/Mod/Fem/Gui/TaskFemConstraintForce.cpp
index 710defeb8..33deb1b00 100644
--- a/src/Mod/Fem/Gui/TaskFemConstraintForce.cpp
+++ b/src/Mod/Fem/Gui/TaskFemConstraintForce.cpp
@@ -116,7 +116,7 @@ TaskFemConstraintForce::TaskFemConstraintForce(ViewProviderFemConstraintForce *C
         ui->listReferences->addItem(makeRefText(Objects[i], SubElements[i]));
     if (Objects.size() > 0)
         ui->listReferences->setCurrentRow(0, QItemSelectionModel::ClearAndSelect);
-    ui->lineDirection->setText(dir.isEmpty() ? tr("") : dir);
+    ui->lineDirection->setText(dir.isEmpty() ? QString() : dir);
     ui->checkReverse->setChecked(reversed);
 
     ui->spinForce->blockSignals(false);
@@ -267,7 +267,7 @@ void TaskFemConstraintForce::onCheckReverse(const bool pressed)
 
 double TaskFemConstraintForce::getForce(void) const
 {
-    return ui->spinForce->value();
+    return ui->spinForce->value().getValue();
 }
 
 const std::string TaskFemConstraintForce::getReferences() const
@@ -357,13 +357,15 @@ bool TaskDlgFemConstraintForce::accept()
 
         if (parameterForce->getForce()<=0)
         {
-          QMessageBox::warning(parameter, tr("Input error"), tr("Please specify a force greater than 0"));
+            QMessageBox::warning(parameter, tr("Input error"), tr("Please specify a force greater than 0"));
             return false;
         }
         else
         {
-            Gui::Command::doCommand(Gui::Command::Doc,"App.ActiveDocument.%s.Force = %f",name.c_str(), parameterForce->getForce());
+            QByteArray num = QByteArray::number(parameterForce->getForce());
+            Gui::Command::doCommand(Gui::Command::Doc,"App.ActiveDocument.%s.Force = %s",name.c_str(), num.data());
         }
+
         std::string dirname = parameterForce->getDirectionName().data();
         std::string dirobj = parameterForce->getDirectionObject().data();
         std::string scale = "1";
diff --git a/src/Mod/Fem/Gui/TaskFemConstraintForce.ui b/src/Mod/Fem/Gui/TaskFemConstraintForce.ui
index 83536403d..006f5f4b4 100644
--- a/src/Mod/Fem/Gui/TaskFemConstraintForce.ui
+++ b/src/Mod/Fem/Gui/TaskFemConstraintForce.ui
@@ -34,13 +34,7 @@
       </widget>
      </item>
      <item>
-      <widget class="QDoubleSpinBox" name="spinForce">
-       <property name="minimum">
-        <double>-99999.000000000000000</double>
-       </property>
-       <property name="maximum">
-        <double>99999.000000000000000</double>
-       </property>
+      <widget class="Gui::QuantitySpinBox" name="spinForce">
        <property name="value">
         <double>500.000000000000000</double>
        </property>
@@ -84,6 +78,13 @@
    </item>
   </layout>
  </widget>
+ <customwidgets>
+  <customwidget>
+   <class>Gui::QuantitySpinBox</class>
+   <extends>QWidget</extends>
+   <header>Gui/QuantitySpinBox.h</header>
+  </customwidget>
+ </customwidgets>
  <resources/>
  <connections/>
 </ui>