diff --git a/src/Gui/Icons/bound-expression-unset.svg b/src/Gui/Icons/bound-expression-unset.svg
new file mode 100644
index 0000000000..0f4507bce9
--- /dev/null
+++ b/src/Gui/Icons/bound-expression-unset.svg
@@ -0,0 +1,78 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   width="64px"
+   height="64px"
+   id="svg4069"
+   version="1.1"
+   inkscape:version="0.91 r13725"
+   sodipodi:docname="bound-expression-unset.svg">
+  <defs
+     id="defs4071" />
+  <sodipodi:namedview
+     id="base"
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1.0"
+     inkscape:pageopacity="0.0"
+     inkscape:pageshadow="2"
+     inkscape:zoom="11"
+     inkscape:cx="30.557379"
+     inkscape:cy="35.35507"
+     inkscape:current-layer="layer1"
+     showgrid="true"
+     inkscape:document-units="px"
+     inkscape:grid-bbox="true"
+     inkscape:window-width="1848"
+     inkscape:window-height="1043"
+     inkscape:window-x="66"
+     inkscape:window-y="0"
+     inkscape:window-maximized="1" />
+  <metadata
+     id="metadata4074">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+        <dc:title></dc:title>
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <g
+     id="layer1"
+     inkscape:label="Layer 1"
+     inkscape:groupmode="layer">
+    <path
+       sodipodi:type="arc"
+       style="fill:#ffffff;fill-opacity:1;stroke:#0000ff;stroke-width:4.36290264;stroke-linejoin:round;stroke-miterlimit:4.19999981;stroke-opacity:1;stroke-dasharray:none"
+       id="path2985"
+       sodipodi:cx="325"
+       sodipodi:cy="503.43362"
+       sodipodi:rx="68.571426"
+       sodipodi:ry="61.785713"
+       d="m 393.57143,503.43362 a 68.571426,61.785713 0 1 1 -137.14286,0 68.571426,61.785713 0 1 1 137.14286,0 z"
+       transform="matrix(0.44478506,0,0,0.49741082,-112.73696,-218.43771)" />
+    <text
+       xml:space="preserve"
+       style="font-size:35.82092285px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:center;line-height:125%;letter-spacing:0px;word-spacing:0px;writing-mode:lr-tb;text-anchor:middle;fill:#0000e6;fill-opacity:1;stroke:#ffffff;stroke-width:0.89552319;stroke-opacity:1;font-family:Arial;-inkscape-font-specification:Arial;"
+       x="32.030895"
+       y="41.949329"
+       id="text3755"
+       sodipodi:linespacing="125%"><tspan
+         sodipodi:role="line"
+         id="tspan3757"
+         x="32.030895"
+         y="41.949329"
+         style="font-size:35.82092285px;font-style:italic;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:center;line-height:125%;writing-mode:lr-tb;text-anchor:middle;stroke-width:0.89552319;font-family:Arial;-inkscape-font-specification:Arial Italic;fill:#0000e6;fill-opacity:1;">f(x)</tspan></text>
+  </g>
+</svg>
diff --git a/src/Gui/Icons/resource.qrc b/src/Gui/Icons/resource.qrc
index b155405eb9..2890c9f658 100644
--- a/src/Gui/Icons/resource.qrc
+++ b/src/Gui/Icons/resource.qrc
@@ -42,6 +42,7 @@
         <file>ClassBrowser/type_module.svg</file>
         <file>Std_ViewScreenShot.svg</file>
         <file>bound-expression.svg</file>
+        <file>bound-expression-unset.svg</file>
         <file>breakpoint.svg</file>
         <file>debug-marker.svg</file>
         <file>debug-start.svg</file>
diff --git a/src/Gui/QuantitySpinBox.cpp b/src/Gui/QuantitySpinBox.cpp
index 66262e81d0..642e35dab9 100644
--- a/src/Gui/QuantitySpinBox.cpp
+++ b/src/Gui/QuantitySpinBox.cpp
@@ -229,6 +229,7 @@ end:
     double singleStep;
     QPalette defaultPalette;
     QLabel* iconLabel;
+    int iconHeight;
 };
 }
 
@@ -244,14 +245,16 @@ QuantitySpinBox::QuantitySpinBox(QWidget *parent)
     d_ptr->defaultPalette = lineEdit()->palette();
 
     /* Icon for f(x) */
+    QFontMetrics fm(lineEdit()->font());
+    int frameWidth = style()->pixelMetric(QStyle::PM_SpinBoxFrameWidth);
+    d_ptr->iconHeight = fm.height() - frameWidth;
     d_ptr->iconLabel = new ExpressionLabel(lineEdit());
     d_ptr->iconLabel->setCursor(Qt::ArrowCursor);
-    QPixmap pixmap = getIcon(":/icons/bound-expression.svg", QSize(lineEdit()->sizeHint().height(), lineEdit()->sizeHint().height()));
+    QPixmap pixmap = getIcon(":/icons/bound-expression-unset.svg", QSize(d_ptr->iconHeight, d_ptr->iconHeight));
     d_ptr->iconLabel->setPixmap(pixmap);
-    d_ptr->iconLabel->setStyleSheet(QString::fromAscii("QLabel { border: none; padding: 0px; }"));
+    d_ptr->iconLabel->setStyleSheet(QString::fromAscii("QLabel { border: none; padding: 0px; padding-top: %2px; width: %1px; height: %1px }").arg(d_ptr->iconHeight).arg(frameWidth/2));
     d_ptr->iconLabel->hide();
-    int frameWidth = style()->pixelMetric(QStyle::PM_SpinBoxFrameWidth);
-    lineEdit()->setStyleSheet(QString::fromAscii("QLineEdit { padding-right: %1px } ").arg(d_ptr->iconLabel->sizeHint().width() + frameWidth + 1));
+    lineEdit()->setStyleSheet(QString::fromAscii("QLineEdit { padding-right: %1px } ").arg(d_ptr->iconHeight+frameWidth));
 
     QObject::connect(d_ptr->iconLabel, SIGNAL(clicked()), this, SLOT(openFormulaDialog()));
 }
@@ -304,6 +307,8 @@ void Gui::QuantitySpinBox::setExpression(boost::shared_ptr<Expression> expr)
 
                 lineEdit()->setText(value->getQuantity().getUserString());
                 setReadOnly(true);
+                QPixmap pixmap = getIcon(":/icons/bound-expression.svg", QSize(d_ptr->iconHeight, d_ptr->iconHeight));
+                d_ptr->iconLabel->setPixmap(pixmap);
 
                 QPalette p(lineEdit()->palette());
                 p.setColor(QPalette::Text, Qt::lightGray);
@@ -313,6 +318,8 @@ void Gui::QuantitySpinBox::setExpression(boost::shared_ptr<Expression> expr)
         }
         else {
             setReadOnly(false);
+            QPixmap pixmap = getIcon(":/icons/bound-expression-unset.svg", QSize(d_ptr->iconHeight, d_ptr->iconHeight));
+            d_ptr->iconLabel->setPixmap(pixmap);
             QPalette p(lineEdit()->palette());
             p.setColor(QPalette::Active, QPalette::Text, d->defaultPalette.color(QPalette::Text));
             lineEdit()->setPalette(p);
@@ -352,12 +359,8 @@ void QuantitySpinBox::resizeEvent(QResizeEvent * event)
 
     int frameWidth = style()->pixelMetric(QStyle::PM_SpinBoxFrameWidth);
 
-    QPixmap pixmap = getIcon(":/icons/bound-expression.svg", QSize(lineEdit()->rect().height() - frameWidth * 2,
-                                                                   lineEdit()->rect().height() - frameWidth * 2));
-    d->iconLabel->setPixmap(pixmap);
     QSize sz = d->iconLabel->sizeHint();
-    d->iconLabel->move(lineEdit()->rect().right() - frameWidth - sz.width(),
-                       lineEdit()->rect().top() - frameWidth);
+    d->iconLabel->move(lineEdit()->rect().right() - frameWidth - sz.width(), 0);
 
     try {
         if (isBound() && getExpression()) {
@@ -366,6 +369,8 @@ void QuantitySpinBox::resizeEvent(QResizeEvent * event)
 
             if (value) {
                 setReadOnly(true);
+                QPixmap pixmap = getIcon(":/icons/bound-expression.svg", QSize(d_ptr->iconHeight, d_ptr->iconHeight));
+                d->iconLabel->setPixmap(pixmap);
 
                 QPalette p(lineEdit()->palette());
                 p.setColor(QPalette::Text, Qt::lightGray);
@@ -375,6 +380,9 @@ void QuantitySpinBox::resizeEvent(QResizeEvent * event)
         }
         else {
             setReadOnly(false);
+            QPixmap pixmap = getIcon(":/icons/bound-expression-unset.svg", QSize(d_ptr->iconHeight, d_ptr->iconHeight));
+            d->iconLabel->setPixmap(pixmap);
+    
             QPalette p(lineEdit()->palette());
             p.setColor(QPalette::Active, QPalette::Text, d->defaultPalette.color(QPalette::Text));
             lineEdit()->setPalette(p);