In components/com_fabrik/views/list/tmpl/yourtemplate/default_headings.php, you have a variable
This variable is an array, which is keyed on the full element name and whose values contains the headings for the list
PHP:
Array
(
[jos_element_test___fabrik_internal_id] => fabrik internal id
[jos_element_test___time_date] => time date
[jos_element_test___int] => int
[fabrik_delete] =>
[fabrik_edit] => edit
[fabrik_view] => view details
)
If you remove an entry from the array the corresponding column will not be rendered, so adding the following code to the beginning of default_headings.php
PHP:
unset($this->headings['jos_element_test___time_date']);
will stop the 'time date' column from showing in the list