diff --git a/2015/burton/Makefile b/2015/burton/Makefile
index fd1a7d517..c5d99259a 100644
--- a/2015/burton/Makefile
+++ b/2015/burton/Makefile
@@ -220,7 +220,7 @@ clean:
 
 clobber: clean
 	${RM} -f ${TARGET} ${ALT_TARGET}
-	${RM} -rf *.dSYM
+	${RM} -rf *.dSYM calc ecalc
 	@-if [ -e sandwich ]; then \
 	    ${RM} -f sandwich; \
 	    echo 'ate sandwich'; \