sorry. do you have example on how to do it. this is from my product.php
$grid_settings['colModel'] = array(
array(
'name' => 'image',
'index' => 'image',
'align' => 'center',
'width' => 65,
'sortable' => false,
'search' => false,
),
array(
'name' => 'name',
'index' => 'name',
'align' => 'center',
'width' => 200,
),
array(
'name' => 'new_column',
'index' => 'new_column',
'align' => 'center',
'width' => 120,
),