Starch can be removed from the bottom of your iron by sprinkling a piece of paper with some fine kitchen salt and rubbing the iron over it until the base becomes smooth again.
Another way is to rub the base of the iron with a half of lemon dipped into regular table salt..
* No starch for me these days... Can't remember the last time I used any... I do know it was the spray stuff...'not the boiling water recipe '