diff --git a/src/App/Extension.cpp b/src/App/Extension.cpp
index c26ba5393b4f..52756c28c56e 100644
--- a/src/App/Extension.cpp
+++ b/src/App/Extension.cpp
@@ -111,7 +111,7 @@ std::string Extension::name() const {
         throw Base::RuntimeError("Extension::name: Extension type not set");
     
     std::string temp(m_extensionType.getName());
-    std::string::size_type pos = temp.find_last_of(":");
+    std::string::size_type pos = temp.find_last_of(':');
 
     if(pos != std::string::npos)
         return temp.substr(pos+1);
diff --git a/src/Base/Interpreter.cpp b/src/Base/Interpreter.cpp
index 24202b79d183..0e0a3f100400 100644
--- a/src/Base/Interpreter.cpp
+++ b/src/Base/Interpreter.cpp
@@ -792,7 +792,7 @@ int getSWIGVersionFromModule(const std::string& module)
             Py::String file(mod.getAttr("__file__"));
             std::string filename = (std::string)file;
             // file can have the extension .py or .pyc
-            filename = filename.substr(0, filename.rfind("."));
+            filename = filename.substr(0, filename.rfind('.'));
             filename += ".py";
             boost::regex rx("^# Version ([1-9])\\.([0-9])\\.([0-9]+)");
             boost::cmatch what;
diff --git a/src/Base/Writer.cpp b/src/Base/Writer.cpp
index 0f5a0c48d67d..a8340da82b8e 100644
--- a/src/Base/Writer.cpp
+++ b/src/Base/Writer.cpp
@@ -317,7 +317,7 @@ void FileWriter::writeFiles(void)
         if (shouldWrite(entry.FileName, entry.Object)) {
             std::string filePath = entry.FileName;
             std::string::size_type pos = 0;
-            while ((pos = filePath.find("/", pos)) != std::string::npos) {
+            while ((pos = filePath.find('/', pos)) != std::string::npos) {
                 std::string dirName = DirName + "/" + filePath.substr(0, pos);
                 pos++;
                 Base::FileInfo fi(dirName);
diff --git a/src/Gui/AutoSaver.cpp b/src/Gui/AutoSaver.cpp
index 4f074db8914a..9343d9cd3573 100644
--- a/src/Gui/AutoSaver.cpp
+++ b/src/Gui/AutoSaver.cpp
@@ -375,7 +375,7 @@ void RecoveryWriter::writeFiles(void)
         if (shouldWrite(entry.FileName, entry.Object)) {
             std::string filePath = entry.FileName;
             std::string::size_type pos = 0;
-            while ((pos = filePath.find("/", pos)) != std::string::npos) {
+            while ((pos = filePath.find('/', pos)) != std::string::npos) {
                 std::string dirName = DirName + "/" + filePath.substr(0, pos);
                 pos++;
                 Base::FileInfo fi(dirName);
diff --git a/src/Gui/DAGView/DAGModel.cpp b/src/Gui/DAGView/DAGModel.cpp
index c7be3833969a..6d56aaf83b26 100644
--- a/src/Gui/DAGView/DAGModel.cpp
+++ b/src/Gui/DAGView/DAGModel.cpp
@@ -893,7 +893,7 @@ void Model::updateStates()
 std::size_t Model::columnFromMask(const ColumnMask &maskIn)
 {
   std::string maskString = maskIn.to_string();
-  return maskString.size() - maskString.find("1") - 1;
+  return maskString.size() - maskString.find('1') - 1;
 }
 
 RectItem* Model::getRectFromPosition(const QPointF& position)
diff --git a/src/Mod/Fem/App/FemMesh.cpp b/src/Mod/Fem/App/FemMesh.cpp
index 062dce28aefe..11e77fbdf086 100644
--- a/src/Mod/Fem/App/FemMesh.cpp
+++ b/src/Mod/Fem/App/FemMesh.cpp
@@ -1023,7 +1023,7 @@ void FemMesh::readNastran(const std::string &Filename)
     {
         std::getline(inputfile,line1);
         if (line1.size() == 0) continue;
-        if (!nastran_free_format && line1.find(",")!= std::string::npos)
+        if (!nastran_free_format && line1.find(',')!= std::string::npos)
             nastran_free_format = true;
         if (!nastran_free_format && line1.find("GRID*")!= std::string::npos ) //We found a Grid line
         {
diff --git a/src/Mod/Mesh/App/Core/MeshIO.cpp b/src/Mod/Mesh/App/Core/MeshIO.cpp
index 8f2f7a490f68..c8e18de8050a 100644
--- a/src/Mod/Mesh/App/Core/MeshIO.cpp
+++ b/src/Mod/Mesh/App/Core/MeshIO.cpp
@@ -1624,7 +1624,7 @@ bool MeshInput::LoadNastran (std::istream &rstrIn)
         if (line.find("GRID*") == 0) {
             assert(0);
         }
-        else if (line.find("*") == 0) {
+        else if (line.find('*') == 0) {
             assert(0);
         }
         // insert the read-in vertex into a map to preserve the order
diff --git a/src/Mod/Path/App/Path.cpp b/src/Mod/Path/App/Path.cpp
index a5e51efcf9ac..bf6b2af172f6 100644
--- a/src/Mod/Path/App/Path.cpp
+++ b/src/Mod/Path/App/Path.cpp
@@ -261,7 +261,7 @@ void Toolpath::setFromGCode(const std::string instr)
             }
             mode = "comment";
             last = found;
-            found = str.find_first_of(")", found+1);
+            found = str.find_first_of(')', found+1);
         } else if (str[found] == ')') {
             // end of comment
             std::string gcodestr = str.substr(last, found-last+1);
diff --git a/src/Mod/TechDraw/App/HatchLine.cpp b/src/Mod/TechDraw/App/HatchLine.cpp
index b822e4437612..b21eb2cb723e 100644
--- a/src/Mod/TechDraw/App/HatchLine.cpp
+++ b/src/Mod/TechDraw/App/HatchLine.cpp
@@ -343,7 +343,7 @@ bool  PATLineSpec::findPatternStart(std::ifstream& inFile, std::string& parmName
              (line.empty()) )  {           //is cr/lf empty?
              continue;
          } else if (nameTag == "*") {
-             commaPos = line.find(",",1);
+             commaPos = line.find(',',1);
              if (commaPos != std::string::npos) {
                   patternName = line.substr(1,commaPos-1);
              } else {
@@ -396,7 +396,7 @@ std::vector<std::string> PATLineSpec::getPatternList(std::string& parmFile)
         std::string nameTag = line.substr(0,1);               //dupl code here
         unsigned long int commaPos;
         if (nameTag == "*") {  //found a pattern
-            commaPos = line.find(",",1);
+            commaPos = line.find(',',1);
             std::string patternName;
             if (commaPos != std::string::npos) {
                  patternName = line.substr(1,commaPos-1);
diff --git a/src/Mod/TechDraw/App/LineGroup.cpp b/src/Mod/TechDraw/App/LineGroup.cpp
index 1b4308a07822..d8f373eb7ed1 100644
--- a/src/Mod/TechDraw/App/LineGroup.cpp
+++ b/src/Mod/TechDraw/App/LineGroup.cpp
@@ -148,7 +148,7 @@ std::string LineGroup::getRecordFromFile(std::string parmFile, std::string group
              (line.empty()) )  {           //is cr/lf empty?
              continue;
          } else if (nameTag == "*") {
-             commaPos = line.find(",",1);
+             commaPos = line.find(',',1);
              if (commaPos != std::string::npos) {
                   foundName = line.substr(1,commaPos-1);
              } else {