diff --git a/interfaces/cython/cantera/onedim.pyx b/interfaces/cython/cantera/onedim.pyx
index b8d73697b..8f0b9da21 100644
--- a/interfaces/cython/cantera/onedim.pyx
+++ b/interfaces/cython/cantera/onedim.pyx
@@ -801,13 +801,15 @@ cdef class Sim1D:
 class FlameBase(Sim1D):
     """ Base class for flames with a single flow domain """
 
-    def __init__(self, domains, gas, grid):
+    def __init__(self, domains, gas, grid=None):
         """
         :param gas:
             object to use to evaluate all gas properties and reaction rates
         :param grid:
             array of initial grid points
         """
+        if grid is None:
+            grid = np.linspace(0.0, 0.1, 6)
         self.flame.grid = grid
         super().__init__(domains)
         self.gas = gas
@@ -1009,7 +1011,7 @@ for attr in ['forward_rates_of_progress', 'reverse_rates_of_progress', 'net_rate
 class FreeFlame(FlameBase):
     """A freely-propagating flat flame."""
 
-    def __init__(self, gas, grid):
+    def __init__(self, gas, grid=None):
         """
         A domain of type FreeFlow named 'flame' will be created to represent
         the flame. The three domains comprising the stack are stored as
@@ -1053,7 +1055,7 @@ class FreeFlame(FlameBase):
 class BurnerFlame(FlameBase):
     """A burner-stabilized flat flame."""
 
-    def __init__(self, gas, grid):
+    def __init__(self, gas, grid=None):
         """
         :param gas:
             `Solution` (using the IdealGas thermodynamic model) used to
@@ -1105,7 +1107,7 @@ class BurnerFlame(FlameBase):
 class CounterflowDiffusionFlame(FlameBase):
     """ A counterflow diffusion flame """
 
-    def __init__(self, gas, grid):
+    def __init__(self, gas, grid=None):
         """
         :param gas:
             `Solution` (using the IdealGas thermodynamic model) used to
@@ -1217,7 +1219,7 @@ class CounterflowDiffusionFlame(FlameBase):
 
 class ImpingingJet(FlameBase):
     """An axisymmetric flow impinging on a surface at normal incidence."""
-    def __init__(self, gas, grid, surface=None):
+    def __init__(self, gas, grid=None, surface=None):
         """
         :param gas:
             `Solution` (using the IdealGas thermodynamic model) used to
diff --git a/interfaces/cython/cantera/test/test_onedim.py b/interfaces/cython/cantera/test/test_onedim.py
index 8943a3366..2a9f16c4d 100644
--- a/interfaces/cython/cantera/test/test_onedim.py
+++ b/interfaces/cython/cantera/test/test_onedim.py
@@ -49,11 +49,12 @@ class TestOnedim(utilities.CanteraTest):
 
 
 class TestFreeFlame(utilities.CanteraTest):
+    tol_ss = [1.0e-5, 1.0e-13]  # [rtol atol] for steady-state problem
+    tol_ts = [1.0e-4, 1.0e-10]  # [rtol atol] for time stepping
+
     def create_sim(self, p, Tin, reactants):
 
         initial_grid = [0.0, 0.001, 0.01, 0.02, 0.029, 0.03]  # m
-        tol_ss = [1.0e-5, 1.0e-13]  # [rtol atol] for steady-state problem
-        tol_ts = [1.0e-4, 1.0e-10]  # [rtol atol] for time stepping
 
         # IdealGasMix object used to compute mixture properties
         self.gas = ct.Solution('h2o2.xml')
@@ -61,8 +62,8 @@ class TestFreeFlame(utilities.CanteraTest):
 
         # Flame object
         self.sim = ct.FreeFlame(self.gas, initial_grid)
-        self.sim.flame.set_steady_tolerances(default=tol_ss)
-        self.sim.flame.set_transient_tolerances(default=tol_ts)
+        self.sim.flame.set_steady_tolerances(default=self.tol_ss)
+        self.sim.flame.set_transient_tolerances(default=self.tol_ts)
 
         # Set properties of the upstream fuel-air mixture
         self.sim.inlet.T = Tin
@@ -212,8 +213,11 @@ class TestFreeFlame(utilities.CanteraTest):
 
         self.sim.save(filename, 'test', loglevel=0)
 
-        self.create_sim(ct.one_atm, Tin, reactants)
-        self.sim.energy_enabled = False
+        # Create flame object with dummy initial grid
+        self.sim = ct.FreeFlame(self.gas)
+        self.sim.flame.set_steady_tolerances(default=self.tol_ss)
+        self.sim.flame.set_transient_tolerances(default=self.tol_ts)
+
         self.sim.restore(filename, 'test', loglevel=0)
 
         P2a = self.sim.P