# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1490959820 -7200
# Node ID 6a90399652a5ac2562d24448faca3179b20a97c1
# Parent  963554290d95ab90f4a9fd81e523aefdd37bc87a
Added options to configure the back socket arrangement, any holes in the back
piece for securing the pieces, and for adjustment of the hole radius.

diff -r 963554290d95 -r 6a90399652a5 cartridge.scad
--- a/cartridge.scad	Thu Feb 16 23:26:02 2017 +0100
+++ b/cartridge.scad	Fri Mar 31 13:30:20 2017 +0200
@@ -1,5 +1,5 @@
 /*
-Copyright (C) 2014, 2015, 2016 Paul Boddie
+Copyright (C) 2014, 2015, 2016, 2017 Paul Boddie <paul@boddie.org.uk>
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -33,11 +33,33 @@
 	BACK_PLUG = 0;
 	BACK_SOCKET = 1;
 
-	/* Set this to the desired lug type. */
+	/*
+	Set this to the desired lug type.
+	The back plug is a normal plug that connects with the front socket.
+	The back socket is the same kind of tube as the front socket, permitting
+	the insertion of screws or nuts through the case to hold both pieces
+	together.
+	*/
 
 	BACK_LUG = BACK_PLUG;
 
 	/*
+	With the back socket chosen, a through-hole can be requested so that
+	a nut and bolt arrangement can be used.
+	Otherwise, a hole will only exist to screw things through the front of
+	the cartridge into the front and back sockets.
+	*/
+
+	BACK_SOCKET_HOLE = 0;
+
+	/*
+	Set the plug and (partial) through-hole radius.
+	Adjust this for the screws or bolts to be used when using a back socket.
+	*/
+
+	BACK_PLUG_RADIUS = 5.5 / 2;
+
+	/*
 	Configure the generated shapes.
 	For the absolute simplest shape (for basic 3D printers)...
 
@@ -445,7 +467,7 @@
 	pcb_back_lug_depth = pcb_back_support_depth +
 		pcb_lug_mating_depth;
 	pcb_back_lug_inner_radius = 1.0;
-	pcb_back_lug_outer_radius = 5.5 / 2;
+	pcb_back_lug_outer_radius = BACK_PLUG_RADIUS;
 
 	/*
 	The cross detail on the back lug is intended to resist the front lug,
@@ -1292,7 +1314,7 @@
 
 					/* Back socket holes. */
 
-					if (BACK_LUG == BACK_SOCKET) {
+					if ((BACK_LUG == BACK_SOCKET) && (BACK_SOCKET_HOLE == 1)) {
 
 						if (MODEL == ROM_CARTRIDGE) {
 							pcb_back_socket_hole(-1);