Here is the problem, it is extremely difficult to get a blade THROUGH the undercoat, so the blade either goes directly against the skin and the dog ends up shaved. Gives him no protection against the sun. Yes it will grow back but he needs sunscreen in the meantime and also protection against fleas.
It is preferable instead to wait until he has shed the bulk of his undercoat, then take him to a groomer. If they bathe and then use a super blower they should be able to get out the rest, then they can use a #4 or a plastic blade and the result should be a coat that is only an inch or two long.
This doesn’t look as hideous as a shaved mal, still gives him protection from the sun.
It is a hell of a job though, so be prepared to spend some bucks at the groomer.
In the meantime, get yourself a rake and work on him to get rid of as much undercoat as you can. I have akitas and we go through the big shed 2x a year when we are all knee deep in fluff! I live in the tropics and have never shaved him, I just brush out the undercoat and then the top coat is relatively fine and the heat does not bother him. Actually he seems to like it, I often find him lying in the full sun.