diff --git a/Haas_Mills_BIDC/Bechtel DT.cps b/Haas_Mills_BIDC/Bechtel DT.cps
index 2a04feb..9ddc390 100644
--- a/Haas_Mills_BIDC/Bechtel DT.cps	
+++ b/Haas_Mills_BIDC/Bechtel DT.cps	
@@ -515,6 +515,8 @@ staticProperties = {
   const X_TRAVEL_LIMIT = -20;
   const Y_TRAVEL_LIMIT = -16;
 
+  const MAX_TOOL_NUM = 20;
+
 var singleLineCoolant = false; // specifies to output multiple coolant codes in one line rather than in separate lines
 // samples:
 // {id: COOLANT_THROUGH_TOOL, on: 88, off: 89}
@@ -1367,7 +1369,7 @@ function onOpen() {
     // also maybe anonymous
     // TODO: tool.getNumberOfTools needs to be machine-specific constant
     function invalidToolNum(toolNum) {
-      return (toolNum < 1 || toolNum > tools.getNumberOfTools() || tools.getTool(toolNum) == undefined);
+      return (toolNum < 1 || toolNum > MAX_TOOL_NUM);
     }
 
     // parse string for specific tools to load
diff --git a/Haas_Mills_BIDC/Bechtel VF2.cps b/Haas_Mills_BIDC/Bechtel VF2.cps
index 108f24e..e95f503 100644
--- a/Haas_Mills_BIDC/Bechtel VF2.cps	
+++ b/Haas_Mills_BIDC/Bechtel VF2.cps	
@@ -515,6 +515,8 @@ staticProperties = {
   const X_TRAVEL_LIMIT = -30;
   const Y_TRAVEL_LIMIT = -15;
 
+  const MAX_TOOL_NUM = 20;
+
 var singleLineCoolant = false; // specifies to output multiple coolant codes in one line rather than in separate lines
 // samples:
 // {id: COOLANT_THROUGH_TOOL, on: 88, off: 89}
@@ -1367,7 +1369,7 @@ function onOpen() {
     // also maybe anonymous
     // TODO: tool.getNumberOfTools needs to be machine-specific constant
     function invalidToolNum(toolNum) {
-      return (toolNum < 1 || toolNum > tools.getNumberOfTools() || tools.getTool(toolNum) == undefined);
+      return (toolNum < 1 || toolNum > MAX_TOOL_NUM);
     }
 
     // parse string for specific tools to load
diff --git a/Haas_Mills_BIDC/Bechtel VF4.cps b/Haas_Mills_BIDC/Bechtel VF4.cps
index 882c1c2..7522560 100644
--- a/Haas_Mills_BIDC/Bechtel VF4.cps	
+++ b/Haas_Mills_BIDC/Bechtel VF4.cps	
@@ -515,6 +515,7 @@ staticProperties = {
   const X_TRAVEL_LIMIT = -50;
   const Y_TRAVEL_LIMIT = -20;
 
+  const MAX_TOOL_NUM = 20;
 var singleLineCoolant = false; // specifies to output multiple coolant codes in one line rather than in separate lines
 // samples:
 // {id: COOLANT_THROUGH_TOOL, on: 88, off: 89}
@@ -1367,7 +1368,7 @@ function onOpen() {
     // also maybe anonymous
     // TODO: tool.getNumberOfTools needs to be machine-specific constant
     function invalidToolNum(toolNum) {
-      return (toolNum < 1 || toolNum > tools.getNumberOfTools() || tools.getTool(toolNum) == undefined);
+      return (toolNum < 1 || toolNum > MAX_TOOL_NUM);
     }
     
     // parse string for specific tools to load