Survive! GSO 4.1

Survive! Knives is a one man operation, run by Guy Seiferd in Gettysburg Pennsylvania USA: https://www.surviveknives.com/
This is his model GSO 4.1, a sturdy allround fixed blade in M390 stainless & green canvas Micarta.

Specs:

Overall length: 22,7 cm
Blade length: 11,0 cm
Blade thickness: 4,0 mm
Steel: M390 stainless (third generation powdered metal, heat treated at Peter's Heat Treat)
Hardness: 60 HRC
Handle material: Green Canvas Micarta, contoured & blasted
Weight: 185 grams
For now without a sheath

It seems some people had their doubts about the M390 stainless used in the GSO 4.1, so Guy made a new clip:

http://www.youtube.com/watch?v…g&feature=player_embedded

Since i had some very slight edge chipping (seen through a magnifying glass) after hacking & cutting some dried oak (probably due to the rather coarse edge), i decided to thin the edge a bit and also refine it just a little.
Will see how this edge holds up on the same wood in a few days.

With the original 40 degrees inclusive coarse edge:

New, somewhat finer & slightly convex edge with an edge angle between 25 and 30 degrees inclusive:

Reprofiling was done freehand on the watercooled black silicon Tormek stone, refining with the grit 60 Rubber Wheel.
The new edge shaves hair above skinlevel and still has quite a lot of bite.

Today i had the chance to test the new edge in the woods again;

As expected the knife cuts way better thanks to the reduced edge angle, not only paper & cardboard, but also all kinds of green & dry wood.
Bite is also still very good.

However: after chopping a deep V-notch in the edge of a "forest bench" (a piece of seasoned oak timber on wooden blocks: very hard stuff) there was microchipping (but almost no flattening) almost along the entire edge.
Judging from the scratches in the bevels at least part of it was due to minute small sand particles trapped in the wood surface, so that would possibly also have happened on larger edge angles.
Most of it was only visible when seen through the magnifying glass of my Victorinox SwissChamp, but some of it could also be seen by the naked eye (with good lighting)

Shaving hair on the back of my hand or my calf is also not possible anymore, but the knife still cuts all kinds of green & dry wood very well.
Copy paper can also still be sliced, but you can feel the microchips.

In a few days i will enlarge the edge angle to an even 30 degrees with the same grit 60 Rubber Wheel finish, and then i will find myself a nice piece of seasoned oak again (this time without the sand particles) to do some more testing.

Another try, now with a slightly convex 30 degrees inclusive edge angle, as can be seen in this picture with my Tormek angle measure:

First i removed the old & weakened edge with microchips by slicing several times straight into a silicium carbide stone (tip from Cliff Stamp), and then put on a completely new edge with the hardrubber grit 60 Rubber Wheel.

Now i always use 2 different tests after the deburring process on the Tormek leather wheel:

1) Cut straight into the edge of a piece of underlayment (wooden multiplex) to remove possible miniscule (but sometimes very stubborn) pieces of burr ( with subsequent a few more passes on the Tormek leather wheel, followed by a visual check with the magnifying glass in my Victorinox SwissChamp)

2) Then 1 or 2 forceful cuts straight into the edge of a old piece of desk (wooden multiplex with hard polymer top layer) to test the strength of the new edge. (followed by another visual check with the magnifying glass)

After this the edge must be completely free of damage and should also be able to shave effortlessly the hair on the back of my hand (or calf)

However: after the second test with the GSO 4.1 and with the magnifying glass i still saw a few tiny microchips and also some flattening, so instead of increasing the 30 degrees edge angle i decided to refine it with the soft rubber grit 180 Rubber Wheel.
After the following deburring on the leather wheel the edge passed both tests: seen through the magnifying glass there were no signs of edge damage anymore: no microchips and no flattening.
Sharpness is also more than acceptable i would think:

Treetopping armhair: check
Slicing single layer toiletpaper: check

One of the coming days i will find out how this edge will handle some batoning, and i will also try to locate a nice piece of seasoned oak again.

Wonderful hobby,

Today i did a little hiking in the woods near my house, so i could play with my GSO 4.1 some more.
On the trails there is always some clearing to do, and this time i got to baton 4 narrow spruce trees (diameter 4 to 6 inches) that had been blown over the footpath with the use of my recoilless hammer i took with me for the occasion (didn't want to find a suitable branch first and the hammer strikes more precise)
Due to the nylon heads there is no chance of damaging the back of the knife, and thanks to the lead shot filling it still has quite a lot of impact.
At home i took a quick pic and then cleaned the knife from resin etc.

On inspection by daylight there was absolutely no damage visible to the edge with the naked eye: no chipping & no flattening.
Doing the same with the magnifying glass in my SwissChamp and with the same lighting conditions i could spot some extremely minimal edge damage: one spot where (judging by the scratches in the bevels) the edge was probably hit by a tiny grain of sand and some very very small spots which reflected a bit of light.
Thus ends my nitpicking.

The sharpness of the edge had decreased from treetopping/hairwhittling to an easily shaving sharpness: the edge still shaves the hair on the back of my hand and my calf with the greatest of ease, both with the growth as against it.
NB: this was done with the edge reprofiled by me to an ever so slightly convex 30 degrees inclusive angle, which also is a bit finer in edge finish than straight from Survive! Knives.

Good stuff this M390 steel,