can't remember if i've asked any of these beofre, but my subscribed threads still crashes my PC for some reason

anyways,

need to put a breather in my axle. i could put it in the dif cover, but putting it in the axle would really be better.

questions:
1) places like gartrac put them in the diff casing itself. would drilling the axle tube weaken it at all? the tube must be about 10mm thick, and cost me a LOT to build so far (must be about £1000, so i don't want to ruin it now)
so is it safe to drill the tube and put it there?

2) how to fit a hose barb? weld or drill and tap?

3) if drill and tap is probably better, if i'm tapping a taper thread (most hose barbs seem to be taper thread) is there anything special about drilling? or is it just a normal drill i use?

i think i've got a hose barb in the garage, brass it is, that should be fine shouldn't it?

Its acceptable, and common, to tap a parallel BSP female thread and use a male taper threaded fitting.

I would say that idealy the breather should be fitted to the diff casing, and as high on that as is possable, and then extended as long as possable upwards. IMHO Cheers Ray