I am at least developing a stong dislike. I was surface grinding two blanks (unheatreated) to get the scale off, taking off 1000th at a time, and the blanks curled up into a nice bow. What's up with that?

Bob,

I bet you don't hate it as much as me. Mine arrived slightly twisted, so I thought no problem, I'll just grind it flat and use a little thinner stock. That was after I tried to heat and straighten it. Ground up some blades and sent them to HT. Three were warped so badly, I put them aside for a rainy day (that may never come :D ). The fourth was pretty straight, but when I was hand finishing, I found inclusions in the steel. I don't really mind losing money on the steel, but I really hate putting work in to something and not being able to finish it. I have two more that have been HTed that I am not going to finish until I have more available time.
Disclaimer: This may just be a bout of bad luck. The steel supplier and manufacturer have stood behind the steel and offered to reimburse me. My heat treater has also done a wonderful job for me, including other steels that are prone to warping (like S90V) with very good results. Even so, I don't think I'll be using any of this steel in the future.

Brett

Well guys, I have to agree on all the warpage stuff. I do quite a little heat treating for other makers and always have warp problems with BG. In fact I am not going to heat treat any more of it due to the warpage. Great steel otherwise!

Rob, does it make a difference on the blank size? Do fixed blades tend to warp more than folder blades? What about thickness? Mine were two 1/8" thick, 11-inch billets for my fighter pattern.

Just a question about the BG-42.Does this steel come cold-rolled and could this be the nature of the problem.

I bought it from Sheffields at a show. I don't know.

Just wondering if it needed stress released,annealed or whatever.

Mike,

Don't quote me because it's been a while, but I think I asked prior to buying, and was told it is hot rolled.

Brett

try getting it annealed before you grind,it may be the trick.All the rolled stuff I have seen or used has tried to warp or twist on me.

Dogman, the worst BG blades that I had warp were tapered tang and hollow ground. They were REALLY squirrely! I have seen this stuff come out of the furnace and then go through a press quench and you look down the blade back and it is dead straight, then look down the edge and the edge is actually warped! If I were going to make folders out of BG I would heat treat then grind.

Mike, the last batch I heat treated I did a stress relieve and it seemed to help, but they were still snakey.

Bob,
Try bead blasting one side of a new piece and see if it bows?? If it does, bead blast the other side and straighten it. Once this is done, and you have removed the surface CRAP:( it should grind pretty straight. I never used BG42 but this has worked for me with other warpy materials when surface grinding. Also use coolant to prevent any heat during grinding.

NEil

Almost bought some at the OKCA show Sunday, but I had second thoughts about it. Must have been esp, this makes me feel good that I didn't buy any, I have enough problems so I don't need anymore. I'll stick with what I know what ever that is. Thanks for the information.
Ray