There were some postings a while back about breaking the
ends of delicate HK axles. I don't see them now and maybe
this was covered already?

But I was trying to salvage a couple the other day and tried
using a nail set to flatten the end a bit and hold the bearing in place. It worked really well. Just slid the bearing onto the axle and set the broken axle end on the flat steel surface of my vise. Concrete floor would work too. Then put the nail set as close to the end of the axle as possible and gave it a little whack with the hammer. Not too hard, took a couple small hits and it flared and slightly bent the last 1/16" and now holds the bearing on really well.