tube-crossdrill-jig: move mainframe holes to middle of slots

diff --git a/tube-crossdrill-jig.scad b/tube-crossdrill-jig.scad
index 4e80849746a5c6e9de906d3de402d705886e823e..72da7c0c80a5ab46a217b7b617303eaef9e39c53 100644 (file)
--- a/tube-crossdrill-jig.scad
+++ b/tube-crossdrill-jig.scad
@@ -47,10 +47,11 @@ slotwidthx = slotwidth * slotslopediag;
 slotxperlen = slotslope / slotslopediag;
 slotyperlen =         1 / slotslopediag;
 
-mainframeholex = backslotedgespace/2 + slotwidth/sqrt(2) +
-  backslotmid2screwhole / sqrt(2);
+mainframeholex = backslotedgespace/2 + slotpluglongerlen * slotxperlen
+  + 0.5 * slotwidth * slotyperlen;
 
-mainframeholey = -backslotmid2screwhole / sqrt(2);
+mainframeholey = -slotpluglongerlen * slotyperlen
+  + 0.5 * slotwidth * slotxperlen;
 
 mainframemaxx = mainframeholex + mainframeextraside;
 mainframeminy = mainframeholey - mainframeextrafront;