diff --git a/cmake/external_projects/tcltk.cmake b/cmake/external_projects/tcltk.cmake
index b071e495..49bc58eb 100644
--- a/cmake/external_projects/tcltk.cmake
+++ b/cmake/external_projects/tcltk.cmake
@@ -1,61 +1,112 @@
 if(APPLE)
-  # use system tcl/tk
-  if((${PYTHON_VERSION_STRING} VERSION_EQUAL "3.7") OR (${PYTHON_VERSION_STRING} VERSION_GREATER "3.7"))
-    # fetch tcl/tk sources to match the one used in Python 3.7
-    ExternalProject_Add(project_tcl
-      URL "https://prdownloads.sourceforge.net/tcl/tcl8.6.8-src.tar.gz"
-      URL_MD5 81656d3367af032e0ae6157eff134f89
-      DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
-      UPDATE_COMMAND "" # Disable update
-      CONFIGURE_COMMAND ""
-      BUILD_COMMAND ""
-      INSTALL_COMMAND ""
-      )
-    ExternalProject_Add(project_tk
-      URL "https://prdownloads.sourceforge.net/tcl/tk8.6.8-src.tar.gz"
-      URL_MD5 5e0faecba458ee1386078fb228d008ba
-      DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
-      UPDATE_COMMAND "" # Disable update
-      CONFIGURE_COMMAND ""
-      BUILD_COMMAND ""
-      INSTALL_COMMAND ""
-      )
-
-    get_filename_component(PYTHON_LIB_DIR ${PYTHON_LIBRARY} DIRECTORY)
-    find_library(TCL_LIBRARY libtcl8.6.dylib PATHS ${PYTHON_LIB_DIR} NO_DEFAULT_PATH)
-    find_library(TK_LIBRARY libtk8.6.dylib PATHS ${PYTHON_LIB_DIR} NO_DEFAULT_PATH)
-
-    set(TCL_DIR ${CMAKE_CURRENT_BINARY_DIR}/dependencies/src/project_tcl)
-    set(TK_DIR ${CMAKE_CURRENT_BINARY_DIR}/dependencies/src/project_tk)
-    set(TCL_INCLUDE_PATH "${TCL_DIR}/generic;${TCL_DIR}/macosx")
-    set(TK_INCLUDE_PATH "${TK_DIR}/generic;${TK_DIR}/macosx;${TK_DIR}/xlib")
-    string(REPLACE ";" "$<SEMICOLON>" TCL_INC "${TCL_INCLUDE_PATH}")
-    string(REPLACE ";" "$<SEMICOLON>" TK_INC "${TK_INCLUDE_PATH}")
-
-    ExternalProject_Add(project_tkdnd
-      URL "http://sourceforge.net/projects/tkdnd/files/TkDND/TkDND%202.8/tkdnd2.8-src.tar.gz"
-      URL_MD5 a6d47a996ea957416469b12965d4db91
-      DEPENDS project_tcl project_tk
-      DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
-      PATCH_COMMAND  patch < ${CMAKE_CURRENT_LIST_DIR}/tkdnd_macosx.patch
-      UPDATE_COMMAND "" # Disable update
-      BUILD_IN_SOURCE 1
-      CMAKE_ARGS
-	      -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}/Contents/MacOS
-	      -DTCL_INCLUDE_PATH=${TCL_INC}
-	      -DTK_INCLUDE_PATH=${TK_INC}
-	      -DTK_LIBRARY=${TK_LIBRARY}
-	      -DTCL_LIBRARY=${TCL_LIBRARY}
-      LOG_DOWNLOAD 1
-      LOG_CONFIGURE 1
-      LOG_BUILD 1
-      LOG_INSTALL 1
+  set(tcl_prefix ${CMAKE_INSTALL_PREFIX})
+  ExternalProject_Add(project_tcl
+    URL "http://sourceforge.net/projects/tcl/files/Tcl/8.6.9/tcl8.6.9-src.tar.gz"
+    URL_MD5 aa0a121d95a0e7b73a036f26028538d4
+    DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+    UPDATE_COMMAND "" # Disable update
+    CONFIGURE_COMMAND ../project_tcl/macosx/configure --enable-threads --enable-framework --prefix=${tcl_prefix} --libdir=${tcl_prefix}/Contents/Frameworks --bindir=${tcl_prefix}/Contents/Frameworks/Tcl.framework/bin
+    BUILD_COMMAND make -j4 binaries libraries
+    INSTALL_COMMAND make install-binaries install-headers install-libraries install-private-headers
+    LOG_DOWNLOAD 1
+    LOG_BUILD 1
+    LOG_CONFIGURE 1
+    LOG_INSTALL 1
     )
-      
-list(APPEND NETGEN_DEPENDENCIES project_tkdnd)
-  else()
-    find_package(TCL 8.5 REQUIRED)
-  endif()
+
+  ExternalProject_Add(project_tk
+    DEPENDS project_tcl
+    URL "http://sourceforge.net/projects/tcl/files/Tcl/8.6.9/tk8.6.9.1-src.tar.gz"
+    URL_MD5 9efe3976468352dc894dae0c4e785a8e
+    DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+    UPDATE_COMMAND "" # Disable update
+    CONFIGURE_COMMAND ../project_tk/macosx/configure --enable-aqua=yes --enable-threads --enable-framework --prefix=${tcl_prefix} --libdir=${tcl_prefix}/Contents/Frameworks --bindir=${tcl_prefix}/Contents/Frameworks/Tcl.framework/bin --with-tcl=${tcl_prefix}/Contents/Frameworks/Tcl.framework
+    BUILD_COMMAND make -j4 binaries libraries
+    INSTALL_COMMAND make install-binaries install-headers install-libraries install-private-headers
+    LOG_DOWNLOAD 1
+    LOG_BUILD 1
+    LOG_CONFIGURE 1
+    LOG_INSTALL 1
+    )
+
+  ExternalProject_Add(project_tkdnd
+    URL "https://sourceforge.net/projects/tkdnd/files/OS%20X%20Binaries/TkDND%202.8/tkdnd2.8-OSX-MountainLion.tar.gz"
+    URL_MD5 2dbb471b1d66c5f391f3c3c5b71548fb
+    DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+    BUILD_IN_SOURCE 1
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND ""
+    INSTALL_COMMAND ${CMAKE_COMMAND} -E copy_directory . ${CMAKE_INSTALL_PREFIX}/../MacOS
+    LOG_DOWNLOAD 1
+    LOG_CONFIGURE 1
+    LOG_BUILD 1
+    LOG_INSTALL 1
+    )
+ 
+  list(APPEND NETGEN_DEPENDENCIES project_tcl project_tk project_tkdnd)
+  list(APPEND CMAKE_PREFIX_PATH ${CMAKE_INSTALL_PREFIX}/Contents/Frameworks)
+  set(TCL_INCLUDE_PATH ${CMAKE_INSTALL_PREFIX}/Contents/Frameworks/Tcl.framework/Headers)
+  set(TCL_LIBRARY ${CMAKE_INSTALL_PREFIX}/Contents/Frameworks/Tcl.framework)
+  set(TK_LIBRARY ${CMAKE_INSTALL_PREFIX}/Contents/Frameworks/Tk.framework)
+  set(TK_INCLUDE_PATH ${CMAKE_INSTALL_PREFIX}/Contents/Frameworks/Tk.framework/Headers)
+
+#   # use system tcl/tk
+#   if((${PYTHON_VERSION_STRING} VERSION_EQUAL "3.7") OR (${PYTHON_VERSION_STRING} VERSION_GREATER "3.7"))
+#     # fetch tcl/tk sources to match the one used in Python 3.7
+#     ExternalProject_Add(project_tcl
+#       URL "https://prdownloads.sourceforge.net/tcl/tcl8.6.8-src.tar.gz"
+#       URL_MD5 81656d3367af032e0ae6157eff134f89
+#       DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+#       UPDATE_COMMAND "" # Disable update
+#       CONFIGURE_COMMAND ""
+#       BUILD_COMMAND ""
+#       INSTALL_COMMAND ""
+#       )
+#     ExternalProject_Add(project_tk
+#       URL "https://prdownloads.sourceforge.net/tcl/tk8.6.8-src.tar.gz"
+#       URL_MD5 5e0faecba458ee1386078fb228d008ba
+#       DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+#       UPDATE_COMMAND "" # Disable update
+#       CONFIGURE_COMMAND ""
+#       BUILD_COMMAND ""
+#       INSTALL_COMMAND ""
+#       )
+# 
+#     get_filename_component(PYTHON_LIB_DIR ${PYTHON_LIBRARY} DIRECTORY)
+#     find_library(TCL_LIBRARY libtcl8.6.dylib PATHS ${PYTHON_LIB_DIR} NO_DEFAULT_PATH)
+#     find_library(TK_LIBRARY libtk8.6.dylib PATHS ${PYTHON_LIB_DIR} NO_DEFAULT_PATH)
+# 
+#     set(TCL_DIR ${CMAKE_CURRENT_BINARY_DIR}/dependencies/src/project_tcl)
+#     set(TK_DIR ${CMAKE_CURRENT_BINARY_DIR}/dependencies/src/project_tk)
+#     set(TCL_INCLUDE_PATH "${TCL_DIR}/generic;${TCL_DIR}/macosx")
+#     set(TK_INCLUDE_PATH "${TK_DIR}/generic;${TK_DIR}/macosx;${TK_DIR}/xlib")
+#     string(REPLACE ";" "$<SEMICOLON>" TCL_INC "${TCL_INCLUDE_PATH}")
+#     string(REPLACE ";" "$<SEMICOLON>" TK_INC "${TK_INCLUDE_PATH}")
+# 
+#     ExternalProject_Add(project_tkdnd
+#       URL "http://sourceforge.net/projects/tkdnd/files/TkDND/TkDND%202.8/tkdnd2.8-src.tar.gz"
+#       URL_MD5 a6d47a996ea957416469b12965d4db91
+#       DEPENDS project_tcl project_tk
+#       DOWNLOAD_DIR ${CMAKE_CURRENT_SOURCE_DIR}/external_dependencies
+#       PATCH_COMMAND  patch < ${CMAKE_CURRENT_LIST_DIR}/tkdnd_macosx.patch
+#       UPDATE_COMMAND "" # Disable update
+#       BUILD_IN_SOURCE 1
+#       CMAKE_ARGS
+# 	      -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}/Contents/MacOS
+# 	      -DTCL_INCLUDE_PATH=${TCL_INC}
+# 	      -DTK_INCLUDE_PATH=${TK_INC}
+# 	      -DTK_LIBRARY=${TK_LIBRARY}
+# 	      -DTCL_LIBRARY=${TCL_LIBRARY}
+#       LOG_DOWNLOAD 1
+#       LOG_CONFIGURE 1
+#       LOG_BUILD 1
+#       LOG_INSTALL 1
+#     )
+#       
+# list(APPEND NETGEN_DEPENDENCIES project_tkdnd)
+#   else()
+#     find_package(TCL 8.5 REQUIRED)
+#   endif()
 
 elseif(WIN32)