My cavalier has a few behaviour issues a lot of them stem from the fact he doesnt get out enough which is my fault as I feel like an idiot walking him at times.  Just before christmas I got a dog behaviourist in unfortunatley that didnt go according to plan.  He was even worse on the lead with her.  I have bought him a canny collar which I must admit works like a treat most of the time but he throws a strop when he wears it clawing at his face he cut his lip the other day which bled.  Does anyone know if this is just a temper tantrum will he calm down.  I dont like to see him hurt himself. Any ideas?

Why do you have him on a canny collar to start with? Is it that he pulls or is it another problem he has? Ive never used a canny collar but have used a halti before on a collie. I think most dogs dislike having something around thier nose if they are not used to it. i dont think i would use a halti or anything that goes around the nose on a short faced breed as they have a tendancy to ride up into the eyes in my experience with them. When i tried one on my old collie he did struggle and try to claw it off at first but i just pulled up slightly and told him to sit and when he did i released the tension and if he tried to pull his head down again to claw at it i pulled up a little again he soon got the hang of it. I see that the Canny collar is attatched to the lead at the back of the head though so i dont think pulling up would help really. If it was me i would go back to using his collar for now and just work on getting him used to walking on the head collar in the house to start with till he doesnt try to take it off, maybe ask him to sit when he starts trying to claw at it and give him a treat if he does or try distracting him when he goes to claw at it.

He pulls and lunges aggresivley at other dogs. He is not aggressive once off the lead he also gets over excited when he sees young children and I know he wont hurt them but for children who dont have a dog it can be quite scary as he is very vocal.  I found the halti did end up too close to his eyes and that is why i wont use it the canny is a lot better.  I will take your advice about putting the canny on in the house we will see where we go with that.  When out with the canny he is also less vocal and so much easier to walk.

I have a Canny Collar too and think it is brilliant. I'm really not a fan of head collars that attach to the lead under the chin.

My pup walks really well on the lead with his normal collar most of the time so I don't use often, but he loves people and dogs, and can, when excited be very bouncy. 

I use it when we go to places I call high excitment areas. (Normally places where there are lots of people, such as shops.) It gives that little extra reinforcement to my commands and he is definitely calmer. I think it can be a really useful aid to training.

My boy didn't really liked wearing it at first but he will mostly ignore it now. I found that simply associating wearing it with getting a treat worked for us.

I use Canny collars too.  I have training leads or what's called 7in1.  What I do, especialy when going on "excitable" walks is to attach the lead at one end to the canny collar and the other to their normal collar; one dog has a plain buckle collar and the other a half check [adjusted so it can't strangle her -only tighten to fit size for a quick check].  One dog is suberb and instantly calmed by the canny collar. The other, especially when very excitable, sometimes complains and tries to get it off her nose.  I think this is because she knows I can control her better with it. 
I also like the Canny collar because you can use it as a plain buckle collar and you don't have to take it off when you let them off lead - you just have to use the D ring 'thingies' to wrap the noseband round their neck, use as many as needed to ensure it's not too tight.
I've found that my dogs have learned that when I use the Canny collars it means that they have to really behave on the lead great when walking out is precarious as has been with the snow and ice we've had over recent months.  A useful training aid and sometimes a 'quick fix' for busy times.
PS I've found that calming myself then calming them -especially making them sit and giving treats and repeatedly passing dogs, kids etc whilst rewarding good behaviour makes a massive difference.  BUT, only do this when you feel calm.

I have used the canny collar on my white german shepherd and she does the same thing as your cavi,  I just ignore her and eventually she gives in she is a big stong dog and can be very hard work as she was a rescue dog, my suggestion is don't give into him and take him out  as often as possible and maybe find a local training club as I feel he needs to be socialised.
Hope this helps you and good luck.

Yes I will keep trying him maybe with more treats to distract him.  I did try it in the house but it failed miserably as it needs a lead attached or he cane take it off to easily my westie is perfect on it so I will just have to keep trying.  Not so good keeping calm when he throws a tantrum I hate the thought of him hurting himself but I will try harder thanks. 

Keeping calm is definitely not easy - that's why I said 'try'.  Just think that every second you are calm is a positive and for the rest of the time 'do no harm'