function na_preload_img()
{ 
  var img_list = na_preload_img.arguments;
  if (document.preloadlist == null) 
    document.preloadlist = new Array();
  var top = document.preloadlist.length;
  for (var i=0; i < img_list.length-1; i++) {
    document.preloadlist[top+i] = new Image;
    document.preloadlist[top+i].src = img_list[i+1];
  } 
}

function na_change_img_src(name, nsdoc, rpath, preload)
{ 
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img) {
    img.altsrc = img.src;
    img.src    = rpath;
  } 
}

function na_restore_img_src(name, nsdoc)
{
  var img = eval((navigator.appName.indexOf('Netscape', 0) != -1) ? nsdoc+'.'+name : 'document.all.'+name);
  if (name == '')
    return;
  if (img && img.altsrc) {
    img.src    = img.altsrc;
    img.altsrc = null;
  } 
}

function show_cnc_machining()
{
  na_change_img_src('image1', 'document', 'images/thumb/blade-1.jpg', true);
	na_change_img_src('image2', 'document', 'images/thumb/DSC00078[1].jpg', true);
	na_change_img_src('image3', 'document', 'images/thumb/blue5-forweb.jpg', true);
}

function show_product_making()
{
  na_change_img_src('image1', 'document', 'images/thumb/Double_Gamescontroller[1].jpg', true);
	na_change_img_src('image2', 'document', 'images/thumb/Enabler1.jpg', true);
	na_change_img_src('image3', 'document', 'images/thumb/Enabler2.jpg', true);
}

function show_vacuum_casting()
{
  na_change_img_src('image1', 'document', 'images/thumb/MVC-005F[1].jpg', true);
	na_change_img_src('image2', 'document', 'images/thumb/IN CHARGER WITH LIDS1.jpg', true);
	na_change_img_src('image3', 'document', 'images/thumb/Equinox_04.jpg', true);
}

function show_spray_finishing()
{
  na_change_img_src('image1', 'document', 'images/thumb/Nike-01-forweb.jpg', true);
	na_change_img_src('image2', 'document', 'images/thumb/Single_Gamescontroller[1].jpg', true);
	na_change_img_src('image3', 'document', 'images/thumb/untitled-2.jpg', true);
}

function restore_images()
{
 na_restore_img_src('image1', 'document');
 na_restore_img_src('image2', 'document');
 na_restore_img_src('image3', 'document');
}