I have some concerns regarding the metallurgy of these axles hopefully some folks like @moon could lend some thought to. I’m sure others could touch on these challenges with unknown metals
I think we have two possibilities - material selection contributed to failure and design.
Design:
This is a two piece axle. That is, the axle is one component and the plate is another. These are either press fit or electrically welded to each other to make the complete rear axle. The failure occurred at that seam
Material: I’m not an expert in alloys of metals by any means. However, I’ve been fixing and building things long enough to have some experience drilling/cutting tool steel and other hardened steels
I did not have my $150 set of cobalt drill bits designed for drilling hardened steel. When I started this extraction, I knew one of two things would happen- I’d be able to drill this axle with what I had to get a seat for the extractor or I wouldn’t.
I was surprised to find that I was EASILY able to drill into the center of this axle with a 3/16” regular black oxide coated drill bit from a ryobi 20 piece drill set bought at Lowe’s- with a cordless. Seriously, this was 3 minutes of work tops
This axle threw chips like it was mild steel. And that was with my cheapest bits and a cordless drill.
Normally, on a snapped hardened axle with an irregular surface, I’d expect a big struggle here
I have really serious reservations about the steel composition. I’ve drilled holes through grade 8 bolts that were 15x harder to drill than this.
@ThermalChild needs to figure out if he wants to run the replacements he received. But I’m a bit skeptical now having cut one of these and seeing they’re no where near the material they should be
