diff --git a/Lib/fontTools/ttLib/tables/TupleVariation.py b/Lib/fontTools/ttLib/tables/TupleVariation.py
index 3a0ae285f..7f5c3a66a 100644
--- a/Lib/fontTools/ttLib/tables/TupleVariation.py
+++ b/Lib/fontTools/ttLib/tables/TupleVariation.py
@@ -1,5 +1,11 @@
 from fontTools.misc.py23 import *
-from fontTools.misc.fixedTools import fixedToFloat, floatToFixed, otRound
+from fontTools.misc.fixedTools import (
+    fixedToFloat as fi2fl,
+    floatToFixed as fl2fi,
+    floatToFixedToStr as fl2str,
+    strToFixedToFloat as str2fl,
+    otRound,
+)
 from fontTools.misc.textTools import safeEval
 import array
 import io
@@ -62,17 +68,17 @@ class TupleVariation(object):
 		for axis in axisTags:
 			value = self.axes.get(axis)
 			if value is not None:
-				minValue, value, maxValue = (float(v) for v in value)
+				minValue, value, maxValue = value
 				defaultMinValue = min(value, 0.0)  # -0.3 --> -0.3; 0.7 --> 0.0
 				defaultMaxValue = max(value, 0.0)  # -0.3 -->  0.0; 0.7 --> 0.7
 				if minValue == defaultMinValue and maxValue == defaultMaxValue:
-					writer.simpletag("coord", axis=axis, value=value)
+					writer.simpletag("coord", axis=axis, value=fl2str(value, 14))
 				else:
 					attrs = [
 						("axis", axis),
-						("min", minValue),
-						("value", value),
-						("max", maxValue),
+						("min", fl2str(minValue, 14)),
+						("value", fl2str(value, 14)),
+						("max", fl2str(maxValue, 14)),
 				        ]
 					writer.simpletag("coord", attrs)
 				writer.newline()
@@ -100,11 +106,11 @@ class TupleVariation(object):
 	def fromXML(self, name, attrs, _content):
 		if name == "coord":
 			axis = attrs["axis"]
-			value = float(attrs["value"])
+			value = str2fl(attrs["value"], 14)
 			defaultMinValue = min(value, 0.0)  # -0.3 --> -0.3; 0.7 --> 0.0
 			defaultMaxValue = max(value, 0.0)  # -0.3 -->  0.0; 0.7 --> 0.7
-			minValue = float(attrs.get("min", defaultMinValue))
-			maxValue = float(attrs.get("max", defaultMaxValue))
+			minValue = str2fl(attrs.get("min", defaultMinValue), 14)
+			maxValue = str2fl(attrs.get("max", defaultMaxValue), 14)
 			self.axes[axis] = (minValue, value, maxValue)
 		elif name == "delta":
 			if "pt" in attrs:
@@ -155,7 +161,7 @@ class TupleVariation(object):
 		result = []
 		for axis in axisTags:
 			_minValue, value, _maxValue = self.axes.get(axis, (0.0, 0.0, 0.0))
-			result.append(struct.pack(">h", floatToFixed(value, 14)))
+			result.append(struct.pack(">h", fl2fi(value, 14)))
 		return bytesjoin(result)
 
 	def compileIntermediateCoord(self, axisTags):
@@ -173,8 +179,8 @@ class TupleVariation(object):
 		maxCoords = []
 		for axis in axisTags:
 			minValue, value, maxValue = self.axes.get(axis, (0.0, 0.0, 0.0))
-			minCoords.append(struct.pack(">h", floatToFixed(minValue, 14)))
-			maxCoords.append(struct.pack(">h", floatToFixed(maxValue, 14)))
+			minCoords.append(struct.pack(">h", fl2fi(minValue, 14)))
+			maxCoords.append(struct.pack(">h", fl2fi(maxValue, 14)))
 		return bytesjoin(minCoords + maxCoords)
 
 	@staticmethod
@@ -182,7 +188,7 @@ class TupleVariation(object):
 		coord = {}
 		pos = offset
 		for axis in axisTags:
-			coord[axis] = fixedToFloat(struct.unpack(">h", data[pos:pos+2])[0], 14)
+			coord[axis] = fi2fl(struct.unpack(">h", data[pos:pos+2])[0], 14)
 			pos += 2
 		return coord, pos