diff --git a/build.py b/build.py
index e8ff5e8..cc68257 100644
--- a/build.py
+++ b/build.py
@@ -38,7 +38,7 @@ with BuildPart() as mop_scraper_holder:
     extrude(profile.sketch, clamp_length / 2)
     extrude(profile.sketch, -clamp_length / 2)
 
-    fillet(mop_scraper_holder.edges().filter_by(Axis.Z), 2)
+    fillet(mop_scraper_holder.edges().filter_by(Axis.Z), (arms_thickness - 0.01) / 2)
 
     with Locations(Plane((screw_pos.X, screw_pos.Y, 0)).rotated((-90, 0, 0))):
         CounterBoreHole(3 / 2, 5.6 / 2, 3.2)