ACROSS

 1  A playboy of this world finds a sweet, dizzy registered nurse, a short one! (7)

 5  Our former president, in short, dined on a primary color, as silk might be, or livestock. (7)

 9  Little devil in a little fish! But it could keep you off-kilter. (7)

10  Blossom and more! Three’s around four if you miss the point. (7)

11,  12 and 13 Fire the mechanism, or go all out? (5,3,5)

14  No toll here! A wee fry, stirred, makes it perfect. (7)

16  Hates the exams, I hear. (7)

18  What the mechanic does to the car could mean a certain fellow has reached the top of the beanstalk! (5,2)

21  Walking along to add a heavy weight here to name a London station. (7)

24  Confused stare makes these of interest. (5)

26  Boss! The number comes before an exclamation of pain. (3)

27  The angel does this for show, and reverses. (5)

28  Birds of a feather? 11 is stirred with Royal Crown shortly to produce it. (7)

29  Change of direction–or directions? Either way, it will be way different! (7)

30  People having a row? It’s just the same old crew. (7)

31  Suffering an eclipse, sundry northeast steamships briefly find arid conditions. (7)

DOWN

 1  and 18 They were famous tumblers. (5,2,7)

 2  You? Me? Him? Her? (7)

 3  Force 2 to leave, and bad vice will end up at the crossroads. (5)

 4  It’s regular after dark, but it sounds more like King Arthur’s round table! (7)

 5  When you’re at this, you’ve had it up to here and don’t know what to do or which way to turn–but it sounds like you’ve lost your sense of humor! (4,3)

 6  It’s a toss-up–lose on purpose or pitch it? (5)

 7  Idolizes the silversmith and his family? (7)

 8  Crazy Theodore’s sister, commonly, stops–just ceases… (7)

15  and 17 …while little Theodore existed, switched, and got thinner and thinner until he almost disappeared! (6)

18  see 1

19  The 6 stops here, but he’s part of the nine, with Tom dear in Paris. (7)

20  Choose Junior! If one does this to others, it is bullying. (5,2)

21  The prisoner of war has a point–communist!–and has specified fuel. (7)

22  Uncle, I’d badly gather relevant parts to comprise. (7)

23  Gee, I hear escorts showing those who exclaim fulsomely, or just “Well, well, well.” (7)

25  Beat it! State animal! (5)

27  Blue? Goose? Straw? Rasp? Chuck? (5)