diff --git a/TermTk/TTkCore/timer.py b/TermTk/TTkCore/timer.py
index 50dcef54..f1806b61 100644
--- a/TermTk/TTkCore/timer.py
+++ b/TermTk/TTkCore/timer.py
@@ -33,7 +33,7 @@ if importlib.util.find_spec('pyodideProxy'):
         _uid = 0
 
         __slots__ = (
-            '_id', '_running',
+            '_id', '_running', '_timer',
             'timeout', '_timerEvent',
             '_delay', '_delayLock', '_quit',
             '_stopTime')
@@ -42,6 +42,7 @@ if importlib.util.find_spec('pyodideProxy'):
             # Define Signals
             self.timeout = pyTTkSignal()
             self._running = True
+            self._timer = None
 
             self._id = TTkTimer._uid
             TTkTimer._uid +=1
@@ -67,17 +68,19 @@ if importlib.util.find_spec('pyodideProxy'):
         def quit(self):
             pass
 
-        def run(self):
-            pass
-
-        @pyTTkSlot(int)
-        def start(self, sec=0):
+        @pyTTkSlot(float)
+        def start(self, sec=0.0):
+            self.stop()
             if self._running:
-                pyodideProxy.setTimeout(int(sec*1000), self._id)
+                self._timer = pyodideProxy.setTimeout(int(sec*1000), self._id)
+                # pyodideProxy.consoleLog(f"Timer {self._timer}")
 
         @pyTTkSlot()
         def stop(self):
-            pass
+            # pyodideProxy.consoleLog(f"Timer {self._timer}")
+            if self._timer:
+                pyodideProxy.stopTimeout(self._timer)
+                self._timer = None
 else:
     # from .log import TTkLog
     class TTkTimer():
@@ -98,8 +101,8 @@ else:
             if self._timer:
                 self._timer.cancel()
 
-        @pyTTkSlot(int)
-        def start(self, sec=0):
+        @pyTTkSlot(float)
+        def start(self, sec=0.0):
             if self._timer:
                 self._timer.cancel()
             self._timer = threading.Timer(sec, self.timeout.emit)
diff --git a/tests/sandbox/Makefile b/tests/sandbox/Makefile
index 80f70c67..ee932f08 100644
--- a/tests/sandbox/Makefile
+++ b/tests/sandbox/Makefile
@@ -39,4 +39,14 @@ buildSandbox: www
 
 	find ../../tmp/TermTk/  -name "*.py" | sed 's,.*tmp/,,' | sort | xargs tar cvzf bin/TermTk.tgz -C ../../tmp
 	find ../../tutorial -name "*.py" | sort | xargs tar cvzf bin/tutorial.tgz
+	find ../../demo/paint.py ../../demo/ttkode.py ../../demo/demo.py ../../demo/showcase/*.* | sort | xargs tar cvzf bin/demo.tgz
+
+buildTestSandbox: www
+	rm -rf bin
+	mkdir -p bin
+
+	$( cd ../../ ; tools/prepareBuild.sh release ; )
+
+	find ../../TermTk/  -name "*.py" | sort | xargs tar cvzf bin/TermTk.tgz
+	find ../../tutorial -name "*.py" | sort | xargs tar cvzf bin/tutorial.tgz
 	find ../../demo/paint.py ../../demo/ttkode.py ../../demo/demo.py ../../demo/showcase/*.* | sort | xargs tar cvzf bin/demo.tgz
\ No newline at end of file
diff --git a/tests/sandbox/sandbox.html b/tests/sandbox/sandbox.html
index bb6f9077..f94fab2a 100644
--- a/tests/sandbox/sandbox.html
+++ b/tests/sandbox/sandbox.html
@@ -144,8 +144,12 @@
             return [term.cols, term.rows]
           },
           setTimeout: function(t, i) {
-            // console.log("TIME",i,t)
-            setTimeout(() => ttk_timer(i), t)
+            // console.log("TIME (Start)",i,t)
+            return setTimeout(() => ttk_timer(i), t)
+          },
+          stopTimeout: function(t) {
+            // console.log("TIME (Stop)",t)
+            clearTimeout(t)
           },
           clearTimeout: function(){
             let highestTimeoutId = setTimeout(";");