If you just want to create an empty table, you have multiple solutions :
1) Use SQL directly with R::exec(). It'll let you do whatever you want.
2) R::dispense() a new bean, R::store() it and then R::trash() it.
3) You can use the writer's createTable() function :
<?php
$R = R::setup('mysql:host=' . DB_HOST . ';dbname=' . DB_NAME, DB_USER, DB_PWD);
$R->writer->createTable("mytable");
?>
Lyn.