its ok....my post was sloppy, yours was straight to the point! <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />

i voted for a no on zero edge....at least from SY

I got mine convex from HD and its amazing cuts through everything like hot knife through butter.

Nail on the head..






This (excaggerated) pic shows the material that needs to be removed if you want to make a zero edge out of a CG edge..
It's between the red and blue lines <img src="/ubbthreads/images/graemlins/smile.gif" alt="" />

On a flat ground blade, I would prefer it not have a true zero edge unless the stock is thick and the blade is narrow, as in the CS Spike. The edge that came on my M9LE was quite good, thick enough to be strong, but thin enough to be sharp. I am content to apply my on convex edge to most flat ground blades. A full convex zero edge is another story. Most Bark Rivers come with those, and they are usually strong enough, and always very sharp. But the LEs are more expensive already. Adding a full convex zero edge would cost a lot more.

I say buy the CG...I'll keep as much steel ,for as long as possible...or if its a chopper let HD VEX it for you for $45 an hour...

Zero edges are nice for soft contact. By that I mean soft cutting like food prep, leather work and soft green woods. There relatively thin and unsupported edge makes zero edged susceptible to chipping when used for hard contact, hard contact being hard woods both green and cured, knots (soft and hard wood) animal bone and cinder blocks just to name a few. Axe maker Gränsfors Bruks generally profiles there axes for soft pine and fir and warn the use on hard cured wood could damage/chip the edge. You need to re profile the edge before attacking the cured oak pile.

The secondary beveled edge maintains more material behind the edge thus supporting it for hard contact/impact. This edge can also be made very sharp and will preform well on soft and hard woods alike. The secondary beveled edge allows usage over a greater range of material whereas the zero edge is more limited. If your tool is targeted towards hard use then the secondary beveled edge makes more sense. If on the other hand your tool is marketed for cutting rather than chopping the Zero edge makes more sense.

I voted for leaving it as is and letting the user tailor it to there needs.

A zero edge doesn't HAVE to be thin - although that's what it will be on a flat grind. But trust me, after handling the killa zilla, it's quite possible to have a full convex zero edge with a LOT OF STEEL behind the edge. <img src="/ubbthreads/images/graemlins/eek.gif" alt="" />

Your quite correct.

The first generation CS Trail Master had a convex zero edge. They were quite sharp and the edge was well supported for hard contact. There were a lot of complaints about sharpening them. I was not really wild about the angular transition on the edge as it was pretty steep. Again it was not made for cutting but rather for general use including chopping.

You also have to take into consideration the width, thickness and material. The width and thickness will give you the angle based on where the grind line starts. For example comparing the Full Flatt grind (spine to edge) to the saber grind (grind line starts at ~half of the width) the saber grind will leave slightly more material behind the edge when taken to zero.

I also mentioned material. The material has to be able to perform for the tools designed purpose. Hard metals tend to chip and soft metals tend to roll and deform when ground thin. There is a balancing act between metal and angle to achieve optimum performance for a given task. There is also a fourth consideration and that is lateral forces. When striking and object the forces are not always parallel to the edge but can also be perpendicular. Lateral (perpendicular) forces at the edge can be massive since they are concentrated on a very small area. The tool can perform perfectly under perfect parallel loading and fail with the slightest lateral load.