Stuart
The blade was tempered yes
This steel is sverker21 (D2)
It was surface ground to thin it a bit when it was still soft (im starting to suspect that surface grind), then took it to another surface grinder for better finish. (the first grinder has something wrong with his machine, so it leaves very wavey surface, but i go to him when i want to remove material) then it was HTed and no problems appeared, i hand sanded it a bit with 120 and no problem, but I was going to surface grinder anyway and felt my hand sanding left bit of deep scratches from surface grinding before (I think youre starting to see how hard things arecforcme around here...)
When i got it from that SGer i saw those cracks, or at least they seem like cracks
Guys, I just want to make sure, you understand the problem is the wavey lines across the blade not the straight lines along its length, righy?
Anyway I will give it a go on my disc sander later and see how things go, probably try what kerosene trick too
Thanks
Will keep you posted