If you never leave home without a knife and bat, you might still be considered to be breaking the law in the UK. What the law boils down to is a potential weapon is only legal if you have a good reason to be carrying it. Carrying your tools to, from and at your place of work would be fine; carrying them anywhere else is not.
To give an example: I used to work on a farm, and I would carry a locking penknife, which is not legal carry without good reason in the UK. Whilst at the farm or journeying between fields, it was legal as I had a reason for having it, but if I popped into a shop to get some lunch whilst on the way, the knife would become illegal as I had no reason to carry one in a supermarket. To fully comply with the law I should've left it locked in the car, although I never did. That's not to say a police officer would be likely to give me a hard time over it if they had stopped me (depending on the reason for stopping me, of course), but if they felt the need to, they could have. I'm no authority but I doubt "self-defence" would be considered a good reason.