led-panel-ceiling-bracket: fix "bolt hole depth change for 12mm long bolts?"

In 97abe544

-bolthead_depth = 5;
+bolthead_depth = 5 + 20 - 8;

is clearly wrong.  We have subtracted 12 from 20 twice but we only
wanted to do it once.

diff --git a/led-panel-ceiling-bracket.scad b/led-panel-ceiling-bracket.scad
index afb7386e5f5ce59e45038436a224611f436d125b..c5be76a298cf33dcf987f32c120886b89aa6a27e 100644 (file)
--- a/led-panel-ceiling-bracket.scad
+++ b/led-panel-ceiling-bracket.scad
@@ -10,7 +10,7 @@ light_height = 12.5;
 hole_from_back = 7.2 + 0.5;
 hole_dia = 3.5 + 0.5;
 bolthead_dia = 7 + 1.0;
-bolthead_depth = 5 + 20 - 8 + 2.7/2;
+bolthead_depth = 5 + 20 - 12 + 2.7/2;
 
 plasfix_dia = 4.5 + 0.5;
 plasfix_head = plasfix_dia * 2;