M.T.
I wouldn't recommend it, unless you're talking about an amicable split in which the exes have an agreement. I wouldn't ever go into court for anything without legal representation. I think that's a big mistake. A lawyer can help him to present himself in the best possible light and will know the legal precedents. A custody battle is not just a he said/she said. Legal counsel will make sure that you don't make a costly mistake.