diff --git a/swing/src/net/sf/openrocket/gui/configdialog/RocketComponentConfig.java b/swing/src/net/sf/openrocket/gui/configdialog/RocketComponentConfig.java
index c963aa6a2..66c94148e 100644
--- a/swing/src/net/sf/openrocket/gui/configdialog/RocketComponentConfig.java
+++ b/swing/src/net/sf/openrocket/gui/configdialog/RocketComponentConfig.java
@@ -338,8 +338,8 @@ public class RocketComponentConfig extends JPanel {
 		m = new DoubleModel(component, "OverrideCGX", UnitGroup.UNITS_LENGTH, 0);
 		// Calculate suitable length for slider
 		DoubleModel length;
-		if (component instanceof ComponentAssembly) {
-			Iterator<RocketComponent> iterator = component.iterator(false);
+		if (component.getChildCount() > 0) {
+			Iterator<RocketComponent> iterator = component.iterator(true);
 			double minL = Double.MAX_VALUE;
 			double maxL = Double.MIN_VALUE;