Cliff Stamp
BANNED
- Joined
- Oct 5, 1998
- Messages
- 17,562
Specifics on the Al Mar Sere 2000 :
http://www.almarknives.com/catalog_2005.shtm#SERE2000
The SERE 2000 is made from VG-10 stainless, 0.15" thick stock, with a high flat grind which tapers to a very thin (0.012-0.016) and acute edge 16 (2), the tip tapers for 1.8" and is 0.91" wide at the back of the taper. The handle is very thick and filling in the grip with a ultra deep clip which attaches to the very end of the handle.
The knife opens very smoothly, 500 (25) g will release the blade from the handle and immediately it is reduced to 200 (25) grams and the blade swings almost effortlessly. The lock is stable under spine impacts both whippy and heavy, however can be released readily under hammer grips and moves readily to disengagement in heavy wrist torques.
This knife was donated for an examination of the lock and blade for strength/stability in wood working (specifically batoning and prying), however I also did some cutting work first as the profile looked very efficient and the blade performed very well and overall had one of the better balanced cutting profiles seen in awhile.
On a 50 lbs push into a phonebook it achieved 175 (7) pages, sliced through 3/8" hemp with 13 (1) lbs and made a push with 21 (1) lbs. It cut through the bottom of a 591 ml pepsi bottle with 55 (2) lbs, and through the bottom of a 2L with 75 (2) lbs. Television cable could be push cut with 60 (2) lbs [1] and the knife pointed sections on 1.5x5x5 cm birch flooring with 9.8 (9) slices.
On some small sections of local softwoods, the Sere 2000 outchopped the Mora 2000 by 92 (2), not even in the same class. The SERE was also in general a much better carving knife on both softwoods like Pine and harder woods like birch and oak. However after the short chopping session (54 chops from the shoulder), the liner lock had compressed the tang of the blade and there was visible play.
The lock was still stable under spine impacts and didn't seem any less secure in general so it was used with wrist impacts to baton a dozen small pieces of various woods :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_baton_wrist.jpg
At first the splitting was attempted with no hand pressure on the handle but even though the wood was selectively chosen to be relatively clear and straight, the small (0.25") knots caused the time to be five times greater without hand stabilization and it only worked to directly split half the wood as the other half the wood would need to be split in sections or by wedges rather than direct batoning which would increase the time even further.
As a result of the wrist impacts the lock had now compressed into the tang heavily and the knife was moving so much that with some wrist shaking it would click back and forth heavily. The amount of force used as noted was light, all the splitting was done while sitting down, using just wrist motion and would take on average 6-12 hits to split a piece of clear wood which would be readily chop split trivially with a large knife.
I benchmarked the impacts in the same way as I did with the X-Ray Vision to insure that the SERE 2000 was recieving the same amount of energy and to further illustrate the level of impacts I asked a visiting trio of gentlemen for assistance. These were a three, five and seven year old, kid. I replaced the knife with a wooden wedge and simply asked them to drive it into the wood with the same baton I was using.
The three year old had some trouble hitting the wedge, and the force he applied was low. The five year old was more focused and had no trouble matching the level of impacts that I was generating was swinging from the shoulder with the stick over his head. He took it pretty seriously. The seven year old determined not to be outdone easily surpassed his younger brother. The kids are generally physically active, but nothing out of the ordinary in terms of physical ability.
As a more demanding task a small piece of wood was chosen which was completely ring knoted, there was no way to split the wood without having to cut through a knot[2], even a small section could not be side split as the wood was only small diameter, so elbow swings were used to drive the SERE 2000 through a knot (splitting it, not chisel cutting it which is *far* worse). The knife took about a dozen kits to clear the knots at which point the wood was just cracked by hand as the other end was knotted as well.
These impacts were twice as energetic as the wrist ones, again still done sitting down with a small wooden baton (under 2" thick and a foot long), the liner lock had collapsed into the handle and was recessed down so it could not be released. A screwdriver was used to check if it could be unlocked which it could, however it was so badly warped and twisted that it cracked before it fully released :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_baton_90.jpg
The problem was that the liner on the SERE not only has the normal milling that most do to make the lock easier to release, it was also skeletonized which made it *much* weaker in terms of twisting and in general resisting the straight compression force of the tang, it would have been left much stronger if the milling had just been made deeper and not been skeletonized. The tang of the blade is also milled in such a way that the liner only makes contact for a small fraction of its height, and the tang is left very rough which accelerates wear.
The blade was then checked for the ability to dig/pry in wood which it had none due to the very thin tip, it could not break out a piece from a clear spruce 2x4" from 1/4" deep, 1/2" deep and at 3/4" deep the tip took a bend of 1/16" to the side thrugh 1/2" back from the tip, 45 (5) lbs was necessary to bring the blade flat to the wood, just wrist torque.
Moving up to a full inch into the wood, the SERE required 70 (5) lbs to cause the knife to crack and it lost 1/2" of tip, the blade was 1/16" thick through the crack, and there was a visible bend through the tip. Inserting the blade into a crack to its full thickness, it required 175 (5) lbs to crack it off through the main blade body :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_final.jpg
The handle was rock solid with no effect by even the heaviest prying so it could seem to support a thicker blade. It would be interesting to duplicate this with a liner which makes full contact with the tang and is not skeletonized and ideally was much wider to reduce pressure and thus compaction.
-Cliff
[1] this chipped the edge a couple of times as the inner cu core bent, the cuts need to be made fairly fast and direct to avoid damage to the edge
[2] the wood can of course be split with wooden wedges and using the knife to cut a starting notch, this takes much longer of course
http://www.almarknives.com/catalog_2005.shtm#SERE2000
The SERE 2000 is made from VG-10 stainless, 0.15" thick stock, with a high flat grind which tapers to a very thin (0.012-0.016) and acute edge 16 (2), the tip tapers for 1.8" and is 0.91" wide at the back of the taper. The handle is very thick and filling in the grip with a ultra deep clip which attaches to the very end of the handle.
The knife opens very smoothly, 500 (25) g will release the blade from the handle and immediately it is reduced to 200 (25) grams and the blade swings almost effortlessly. The lock is stable under spine impacts both whippy and heavy, however can be released readily under hammer grips and moves readily to disengagement in heavy wrist torques.
This knife was donated for an examination of the lock and blade for strength/stability in wood working (specifically batoning and prying), however I also did some cutting work first as the profile looked very efficient and the blade performed very well and overall had one of the better balanced cutting profiles seen in awhile.
On a 50 lbs push into a phonebook it achieved 175 (7) pages, sliced through 3/8" hemp with 13 (1) lbs and made a push with 21 (1) lbs. It cut through the bottom of a 591 ml pepsi bottle with 55 (2) lbs, and through the bottom of a 2L with 75 (2) lbs. Television cable could be push cut with 60 (2) lbs [1] and the knife pointed sections on 1.5x5x5 cm birch flooring with 9.8 (9) slices.
On some small sections of local softwoods, the Sere 2000 outchopped the Mora 2000 by 92 (2), not even in the same class. The SERE was also in general a much better carving knife on both softwoods like Pine and harder woods like birch and oak. However after the short chopping session (54 chops from the shoulder), the liner lock had compressed the tang of the blade and there was visible play.
The lock was still stable under spine impacts and didn't seem any less secure in general so it was used with wrist impacts to baton a dozen small pieces of various woods :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_baton_wrist.jpg
At first the splitting was attempted with no hand pressure on the handle but even though the wood was selectively chosen to be relatively clear and straight, the small (0.25") knots caused the time to be five times greater without hand stabilization and it only worked to directly split half the wood as the other half the wood would need to be split in sections or by wedges rather than direct batoning which would increase the time even further.
As a result of the wrist impacts the lock had now compressed into the tang heavily and the knife was moving so much that with some wrist shaking it would click back and forth heavily. The amount of force used as noted was light, all the splitting was done while sitting down, using just wrist motion and would take on average 6-12 hits to split a piece of clear wood which would be readily chop split trivially with a large knife.
I benchmarked the impacts in the same way as I did with the X-Ray Vision to insure that the SERE 2000 was recieving the same amount of energy and to further illustrate the level of impacts I asked a visiting trio of gentlemen for assistance. These were a three, five and seven year old, kid. I replaced the knife with a wooden wedge and simply asked them to drive it into the wood with the same baton I was using.
The three year old had some trouble hitting the wedge, and the force he applied was low. The five year old was more focused and had no trouble matching the level of impacts that I was generating was swinging from the shoulder with the stick over his head. He took it pretty seriously. The seven year old determined not to be outdone easily surpassed his younger brother. The kids are generally physically active, but nothing out of the ordinary in terms of physical ability.
As a more demanding task a small piece of wood was chosen which was completely ring knoted, there was no way to split the wood without having to cut through a knot[2], even a small section could not be side split as the wood was only small diameter, so elbow swings were used to drive the SERE 2000 through a knot (splitting it, not chisel cutting it which is *far* worse). The knife took about a dozen kits to clear the knots at which point the wood was just cracked by hand as the other end was knotted as well.
These impacts were twice as energetic as the wrist ones, again still done sitting down with a small wooden baton (under 2" thick and a foot long), the liner lock had collapsed into the handle and was recessed down so it could not be released. A screwdriver was used to check if it could be unlocked which it could, however it was so badly warped and twisted that it cracked before it fully released :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_baton_90.jpg
The problem was that the liner on the SERE not only has the normal milling that most do to make the lock easier to release, it was also skeletonized which made it *much* weaker in terms of twisting and in general resisting the straight compression force of the tang, it would have been left much stronger if the milling had just been made deeper and not been skeletonized. The tang of the blade is also milled in such a way that the liner only makes contact for a small fraction of its height, and the tang is left very rough which accelerates wear.
The blade was then checked for the ability to dig/pry in wood which it had none due to the very thin tip, it could not break out a piece from a clear spruce 2x4" from 1/4" deep, 1/2" deep and at 3/4" deep the tip took a bend of 1/16" to the side thrugh 1/2" back from the tip, 45 (5) lbs was necessary to bring the blade flat to the wood, just wrist torque.
Moving up to a full inch into the wood, the SERE required 70 (5) lbs to cause the knife to crack and it lost 1/2" of tip, the blade was 1/16" thick through the crack, and there was a visible bend through the tip. Inserting the blade into a crack to its full thickness, it required 175 (5) lbs to crack it off through the main blade body :
http://i7.photobucket.com/albums/y269/CliffStamp/al%20mar%20sere%202k/al_mar_sere_2k_final.jpg
The handle was rock solid with no effect by even the heaviest prying so it could seem to support a thicker blade. It would be interesting to duplicate this with a liner which makes full contact with the tang and is not skeletonized and ideally was much wider to reduce pressure and thus compaction.
-Cliff
[1] this chipped the edge a couple of times as the inner cu core bent, the cuts need to be made fairly fast and direct to avoid damage to the edge
[2] the wood can of course be split with wooden wedges and using the knife to cut a starting notch, this takes much longer of course
