diff --git a/components/calcValues.vue b/components/calcValues.vue
index f743167..67fb81e 100644
--- a/components/calcValues.vue
+++ b/components/calcValues.vue
@@ -101,10 +101,13 @@ const changeParametres = () => {
         if (full_sections == 0) {
             length = total_length_mm - fence_length - fence_length
         }
+        if ((total_length_mm - ((full_sections * length) + (full_sections * fence_length) + fence_length)) < fence_length) {
+            full_sections -= 1
+        }
     }
 
     if (((full_sections * length) + (full_sections * fence_length) + fence_length) < total_length_mm) {
-        form_state.extra_section = total_length_mm - ((full_sections * length) + (full_sections * fence_length) + fence_length + fence_length)
+        form_state.extra_section = total_length_mm - ((full_sections * length) + (full_sections * fence_length) + fence_length) - fence_length
     } else {
         form_state.extra_section = 0
     }