Spyderco Military BG-42: Who knew?

G

gud4u

Joined
Jan 6, 2004
Messages
551
It seems I wasn't paying attention when BG-42 was the 'in' steel.

I recently purchased a Spyderco Military BG-42, partly for the firmer handle structure due to the added second hidden steel liner and partly because I've never used a BG-42 blade.

Construction, fit and finish are as close to perfect as one would expect for a production folder:
- The scales are both attractive and grippy, thicker than the old G10 scales.
- The handle-flex of the older single-liner G10-scaled Military is gone.
- Blade dimensions are essentially identical.
- Same point-down-only clip configuration.
- Liner-lock arm stable at first 1/3 of locking arc surface.
- Ergonomics are slightly improved, due to matched serrations on both the finger-choil and thumb-ramp.

I'm one of those who prefer a small choil notch at the base of the edge to facilitate honing cleanly to the base of the edge, so out came the Dremel cut-off wheel and the blade now has a small 3/32" choil cut at the base of the edge.

Having no experience with BG-42 steel, I installed my favorite heavy-use compound bevel on the blade (10 degree main bevels, 15 degree micro bevels). Honing the bevels was much faster than either S30V or VG10. Very little burr formation during honing, and cleanly cutting the burr was easy. Bevel-polishing was similarly fast and easy, taking a mirror-polish easily (apparently a very fine-grained steel). Frankly, the easy grindability and polishing worried me a bit - honing effort was similar to AUS8!

Prior to edge-testing, I checked sharpness by a slow newsprint draw slice from choil to tip, and the blade barely whispered through the slice. This BG-42 blade takes a great edge - quickly.

My 'Super Edge Tester' is an old hardwood rake handle (I think it's Hickory). It's my 'standard' test media used to edge-test all my folders. I pointed the rake handle, using heavy pressure to form about a 2" point. No visible or felt edge damage, so I repeated with another fresh pointing. Back to the newsprint to re-check sharpness - no perceptible loss of sharpness at all, and no edge defects from the pointing.

I haven't tested this blade with more acute micro-bevels (tested at 30 degrees included). My 440V Military blade passes the 'rake handle' test with micro-bevels at about 25 degrees included - the edge-holding champ until dethroned.

BG-42 Blade characteristics summary:
- Better/easier/faster grindability than either S30V or VG10.
- Very low burr formation.
- Burr-removal effort is trivial - easily cut off cleanly.
- Bevels take a high polish easily.
- Edge-holding at least as good as S30V or VG10 (with equal compound bevels).

All things considered, I think the BG-42 Military is an outstanding folder in terms of fit, finish, structural strength and blade performance.

You should buy one!

Edit:
What really amazed me about the BG-42 blade (Spyderco claims RC61 hardness) is the ease of grindability compared to other 'premium' steels. Summarizing the edge-formation process and time required:
- Cut the sharpening choil-notch with Dremel cutoff wheel.
- DMT coarse (Blue) diamond hone to take the 10 degree main bevels to burr.
- 800-grit abrasive paper on HandAmerican Scary Sharp glass platen to remove coarse diamond scratches.
- Spyderco DoubleStuff grey hone to cut the burr.
- CrO-loaded leather strop to polish main bevels to mirror finish.
- Spyderco DoubleStuff hone to form 15 degree micro-bevels.
- CrO-loaded leather strop to polish micro-bevels.
- Total re-profile and finish time about one hour!

For comparison/contrast, I've put the same compound bevels on S30V, VG10, ATS34, 440V/S60V and D2 blades, requiring 2 to 3 times as long to finish those blades. Some of those blades never reached the high mirror-polish level of this blade. No long 'chase-the-burr' sessions required. No long progression of many grit stages to reach a high degree of bevel polish.
 
mine just came in, sadly it was delivered to my parents house and won't come out till christmas:grumpy: it is my first spyderco and i can't wait!
ryan
 
As soon as I heard about this knife, I just KNEW I had to have at least one. I'm carrying one in my pocket now, and have a spare in case something happens to this one. This knife is a winner!
 
I always bug Sal for Bg42 knives of different sorts. I like it very much. There are several in the line that I'd just love to see go to BG42. The Millie is superb! Sublime in this version.

Unfortunately for Sal I'm one of many with requests. We ask for less then simple transitions to things like S125V,S15V,M4 ( I even asked Sal for a T1 HSS knife one time ( one never knows when he might need the red hardness these steels can easily maintain) :') Joe L.
 
Nice work. How much of the increase in time is due to the grindability vs burr issues?

BG-42 is essentially ATS-34 with a small amount of vanadium and is processed to give a very clean steel to increase fatigue life.

http://www.timken.com/products/spec...earing/BG42_Bearing.pdf#search="bg-42 timken"

Adding the vanadium should not increase grindability or ease of burr removal, directly anyway, unless it reduced the size/fraction of the chromium carbides. The VIM/VAR process and the higher hardness would likely have these effects though. Regardless though, it sounds like it works very well.

Does anyone know if these were hardened as HSS as that could be an influence as well.

-Cliff
 
I read several articles suggesting BG42 was essentially modified ATS34. If that's so, it's certainly a dramatic improvement on ATS34. The ATS34 blade of my Buck/Strider Tarani gave me fits getting rid of the burr. It just flopped over, like it was hinged, resisting cutoff - so bad that I blunt-ground the edge and started over. I really did waste an hour on burr-removal on that ATS34 blade.

The BG42 blade certainly behaved like a finer-grained steel, in both low burr production and ease of polish. The easy work-up of this blade was similar to AUS8 or Cold Steel Carbon V behavior - not at all what I expected from a 61-hardness stainless steel.

I think we have all come to expect hard 'premium' stainless steels to a bitch to sharpen. BG42 seems a very pleasant exception.
 
In regards to calling a steel "modified ATS-34" this of course doesn't mean you start off with ATS-34, just that was the basis for the steel or it behaves very similar but is enhanced in several rspects. Similar for example how ATS-34 is refered to as modified 440C. Generally you restrain this to similar class steels, thus you would not call M2 modified 1095.

Both BG-42 and ATS-34 are high hardness, high carbide, high heat resisting, stainless steels. I would be interested in a micrograph of typical BG-42, Landes classifies it the same as ATS-34 in terms of carbide size, CPM-S60 is signifiantly finer. It would be interesting to see if other experiences with BG-42 Militaries are similar.

I have never been overly impressed with 154CM/ATS-34, would be curious to see what Wilson's is like, though I think there are better steels. RWL34/CPM-154CM being an obvious choice. You would likely have much favor in that steel, get it run hard of course.

-Cliff
 
Anytime you take a decent to good stainless like ATS34(more accurately 440C) and add 1.2% Vanadium, AND double vacuum melt it, I like it. :thumbup:
 
05dr said:
mine just came in, sadly it was delivered to my parents house and won't come out till christmas:grumpy: it is my first spyderco and i can't wait!
ryan
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Assuming you bought it (and it's not a Christmas present from them) just send your folks 3 or 4 bucks and ask them to mail it to you.

gud4u said:
- The handle-flex of the older single-liner G10-scaled Military is gone.
Click to expand...
Those G-10 scales were pretty rigid, but yes, you can flex the handles a little bit. If the knife is closed you can see the point move to one side or the other as you put pressure on the handle. Still pretty good, tough handles.

With the new 2-liner setup, is this completely gone, or just diminished a little? After all, a thin slice of steel is probably just as easy to bend as a 1/4" slab of G-10.
 
and it's not a Christmas present from them
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unfortunately in purchasing my first busse knife (yeah, nothing could stop me from getting an LE FBM) i essentially blew my budget for the rest of the year. desperately wanting atleast one other large folder for regular use (for me this was a ruckus vs bg42 military) i had them get my christmas present a bit early:rolleyes: but i will have to wait a bit.
ryan
 
With the new 2-liner setup, is this completely gone, or just diminished a little? After all, a thin slice of steel is probably just as easy to bend as a 1/4" slab of G-10.
Click to expand...

I forgot to mention that the BG42 CF scales are thicker then the G10 scales of my older 440V Military: .150" @ CF vs .135" @ G10. Total handle width also grew about .040": .465" @ BG42 vs. .425" for older 440V Military.

Perhaps your strong scandinavian hands are tougher than mine, but I pronounce the handle-flex gone. In multiple attempts to flex the handles, all I can feel is the compression and squirm from the flesh of my fingers. Perhaps a vice and wrench.......?
 
does the s30v/carbon fiber version also have that second hidden lining?
 
Don't know if it is the "best", but it is a possible incremental improvement.

Now waite for the ZDP or SGPS or M4 version, then let's see which is best.
 
I'd still like to see a steel performance comparison of the S30V vs. BG42 in this model/mfg. ... Has it been done? :D
 
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