some years ago I had a problem that lasted quite a few years - drug ppl in the neighbourhood / suburbs.
long story short. If you are unsure if they will use weapons or steel bars, etc .. first check them out how far are they willing to go.
if they group up, perhaps they are just trying to intimidate/scare you. Otoh, if they are a wild party bunch, they might snap at you if the mood strikes - you never know.
in any case, but seriously, manure forks (the small ones with four spikes) have the ability to scare thughs Sh*tless. (that's no joke btw. I -did- have to use it on some assholes)
hint: practice with it - moves like with the aikido stick etc. but beware - this thing can kill easily. there are even smaller ones, perhaps more convenient to use in "self defence". check out some gardening tools shop etc..
use psychology first. check the guys out beforehand to determine if they are types that would truly use weapons or do some damage.
... or get yourself a nice fireman axe.. it looks more manly (in the sense that to the young, could be inebriated guys, this would perhaps more efficiently communicate the "I mean bussiness" message than some manure forks that would provoke laughter until you swing them). But then, they could blame you for assault. (iow, with the axe, you could perhaps just have to "show up" to be taken seriously. but the fork is much nastier when you swing it around - if provoked in a self-defence situation)
in any case, a Gandhi style non-violent solution would be better, but if the threat continues, some self-defence action could be required..