Schempp Rock 'Chopper' idea

[Sumdumguy]

I would definitely be in on this idea! I always liked the look of the Rock Salt but when I handled it I felt it was too light for what I would do with it. Main use of a heavier version for me would be opening coconuts and cutting back brush in the jungle behind my place. I typically use short machetes for opening coconuts but I’d like something a bit heavier that is still thin enough behind the edge to cut well. So for my uses I’d want enough blade stock for weight without being ground like an axe. A tough steel would make it possible to go a bit thinner with the grind no? Tool steels are great but require a lot more care than stainless for jobs like I would be doing. I have a cheap chopper in 1095 that I’ve used for years on coconuts. I admit that I haven’t been the best about maintaining it but man, it is COVERED in rust. How does LC200N toughness compare to something like cruwear or 3V?

Exactly my thoughts about the rust. I want to see it in LC200N to go in a sailboat's OSB. I would imagine that it is plenty tough.

Given a nice Sumo diet, it would make for a heck of a chooper of coconuts and fish heads alike!

[curlyhairedboy]

In my experience, the Lc200n of the Caribbean is pretty tough, but I don't know if we've had any charpies done.

[mark greenman]

Hi Ed,

'Bout time you got here. :p We need your thoughts and wisdom.

For the purposes of discussion, Let's try to narrow down on the ideal tool. Starting with the same basic shape? Grinds? Steel, grip material? etc.

What is the goal of this particular design? A cutting tool that...........................?

sal

Personally, I feel like my Rock Salt is akin to a fine set of aluminum knuckle dusters; great ergo's, but disconcertingly light. The Rock looks like a knife that could chop off a thief's hand in an arabian market, but picking it up it feels more like a chef's knife.

So I'd like to see the size and ergos of the Rock remain the same, but just boost the mass and 'authority' of the knife when chopping vs the current Rock. Yet not so overboard that it loses the ability to be also be used as a knife.

As far as quantifying that, I'm not sure if there's a Chopping equivalent of a CATRA test.

However, here is an excellent comparison video of The Rock vs Fallkniven A1, Cold Steel Trailmaster, and a Hatchet:
https://youtu.be/fGx7aTlgsNA

Test is a pretty simple 30 seconds of light chopping vs a 2x4, to measure the depth of the V cut. You can really see the difference in 'chopping' ability of the Rock vs the A1, despite the A1 being a slightly shorter knife without negative blade angle.

So as far as a somewhat quantifiable design goal, perhaps 'threshold' performance of boosting chopping to the A1's ability, and 'objective' performance of trying to get it to exceed the A1 / close in on the Trailmaster.

[Ed Schempp]

For handle material I like either horse stall mat or neoprene shoe sole material. I've been using oring material for pin stock with 18-20 pins that hold the rubber slabs on on the tang. This eliminates hard or hot spots in high impact cutting. I have used rubber inserts dovetailed into the tang that give a full rubber grip to reduce shock.
My friend Dan Keffler has been using Vanadis 4 for his cutters with success. He is a 4 time Bladesports world champion.
The second photo of my cutters is the one I used the most @ competition, it weighed 17 ounces. The Damascus cutter was a 14.5 ounce knife, it looked like a pin striped shark so I called it Wall Street.

[Surfingringo]

Hey Ed, I went to Gayle Bradley’s shop a few years ago and got to look at some of his choppers with horse stall mat handles. Great feel and grip. I actually considered using something like that on one of my water purposed fixed blades. I seem to recall Sal saying it was kind of a PITA to work with in production? I like the idea of a hard rubber like material for grip and shock absorption. A lot of old dive knives (and some fillets) came with a handle made with a hard rubber like material. Not sure exactly what the material options are but I think something like that would function well.

[mark greenman]

For handle material I like either horse stall mat or neoprene shoe sole material. I've been using oring material for pin stock with 18-20 pins that hold the rubber slabs on on the tang. This eliminates hard or hot spots in high impact cutting. I have used rubber inserts dovetailed into the tang that give a full rubber grip to reduce shock.
My friend Dan Keffler has been using Vanadis 4 for his cutters with success. He is a 4 time Bladesports world champion.
The second photo of my cutters is the one I used the most @ competition, it weighed 17 ounces. The Damascus cutter was a 14.5 ounce knife, it looked like a pin striped shark so I called it Wall Street.

Love the 'Wall Street.' Great name and beautiful knife.

I really like the idea of a rubber / shock absorbing grip.

I'm not too knowledgeable about Injection Moulds. The Rock Salt grips were made with FRN plastic; can the moulds be used for other materials?

For example, say, 75D Polyurethane? This is the soft plastic used in longboard skateboard wheels. Very durable but shock absorbing. If that material (or similar) could be used instead of FRN, but without having to make a new mould, that could provide a sort of 80/20 solution.

Alternatively, Respirene, as used in the Busse / Swamp Rat line of knives:
https://www.materialdatacenter.com/ms/e ... b27ab/6356

[yowzer]

The Santoprene that Benchmade is using in a couple of their new fixed blade knives is pretty nice.

[mark greenman]

I did some 'ballistic pruning' today with the Rock Salt.







Such a comfortable design for making snap cuts.

I really hope we see a Rock Chopper developed; the Rock family is just too good to let slip away.

[Pancake]

I know that it is a part of desing, and a way how to have more mass in front, but the damm recurve is just !!! I don't like recurves, can't sharpen them easily with a stone.

[mark greenman]

Playing with the Rock Salt today, I noticed two possible improvements for the handle of the 'Rock Chopper.'

Regular Rock handle:


Modified 'Rock Chopper' handle:


The first modification is deleting the single 'finger ridge' in the middle of the handle. For me, it creates a mild hot spot, and when chocking up and using the finger choil, my pinky ends up resting on the finger ridge. Much like with pistols, removing finger grooves makes for a more universal fit.

The second modification, and I think more important, is the 'pinky guard' at the bottom of the handle. This is to lock the pinky into the knife when doing a looser grip snap cut with more rotation. It also makes for an overall more secure grip when chopping, as it makes it harder for the knife to slip out of the hand.

The resulting grip ends up looking similar to the other Ed Schempp classic - the Barong. A ergonomic, ridgeless grip, with pronounced guards on both ends.

[curlyhairedboy]

I do like the hook at the end of your modified picture, but maybe a little less pointy.

[bearfacedkiller]

I would like to use it as a woods tool for things like shelter building, firewood prep and clearing shooting lanes for hunting. I live in the northeast so I mostly deal with hardwoods around here. My Schempp Rock just didn’t have the weight for that.

I would like to chop, baton and do some carving. I like a negative blade angle and a slight recurve because for me it makes using it as draw knife easier.

I don’t want bidirectional frn. I don’t really like wearing gloves. Maybe it was the Schempp Rocks light weight forcing me to really muscle it that caused my hands to hurt but I found chopping with the Schempp Rock uncomfortable.

Lastly, the thumb ramp has a sharp point which did not work for me when carving close to the handle. I like to put my thumb on the spine when carving and I ended up rounding the thumb ramp a little. I still want to take more off but since I rarely use the knife it is on the back burner for now.

[JRinFL]

Without gloves, I find the rubber grips to cause blisters much faster than a smooth hard surface. Micarta and smooth G10 may not be appropriate either, but I would still want a smooth firm surface on the grips.

[mark greenman]

Without gloves, I find the rubber grips to cause blisters much faster than a smooth hard surface. Micarta and smooth G10 may not be appropriate either, but I would still want a smooth firm surface on the grips.

Perhaps Longboard Skateboard Wheel material may be the happy medium between FRN/G10 and Rubber:



78A durometer puts it right between truck tire and shoe heel in hardness / flexibility. So capable of providing shock absorption, but still harder/ less 'tacky' on skin then rubber.



It couldn't be smooth, but perhaps the very light pebbling found in some kitchen knives, which is comfortable but non slip:


@78a + light pebbling, that would also allow users who want to pretty easily polish them smooth with sandpaper.

[Sumdumguy]

I would like to use it as a woods tool for things like shelter building, firewood prep and clearing shooting lanes for hunting. I live in the northeast so I mostly deal with hardwoods around here. My Schempp Rock just didn’t have the weight for that.

I would like to chop, baton and do some carving. I like a negative blade angle and a slight recurve because for me it makes using it as draw knife easier.

I don’t want bidirectional frn. I don’t really like wearing gloves. Maybe it was the Schempp Rocks light weight forcing me to really muscle it that caused my hands to hurt but I found chopping with the Schempp Rock uncomfortable.

Lastly, the thumb ramp has a sharp point which did not work for me when carving close to the handle. I like to put my thumb on the spine when carving and I ended up rounding the thumb ramp a little. I still want to take more off but since I rarely use the knife it is on the back burner for now.

This is pretty much hitting the nail on the head for me. I prefer a smoother grip.

Also, as above, make the handle more neutral and had a pinky hook(less pointy).

All that, in LC200N would be ideal.

[Surfingringo]

I was giving some more thought to steel choice on this one and it occurred to me that the H1 version might already have the right steel. Seriously, is there a reason that a heavier Rock couldn’t be done in H1? Overall edge retention would not be as good as something like 4v but we are talking a chopper here and I imagine that H1 is actually tougher than most of the tool steels being mentioned. It would be awesome to have a super tough and completely rust proof chopper! No idea if H1 is even available in that thickness or if it is feasible from a grinding/production standpoint but given the steel’s properties, I think we should at least consider the idea of a thicker, heavier H1 chopper no?

[Sumdumguy]

I would still prefer LC200N. It's a far more well rounded steel and I have yet to see any actual toughness testing side by side with H1.

I know H1 is tough, but LC200N is also ridiculously tough. If H1 is tougher, how much so and is it enough extra to warrant sacrificing the performance gains brought by LC200N?

I want to see an actual comparison. I only have my own usage to compare against. I would take LC200N over H1 any day, in any edge.

Maybe there's another variable that H1 has, but I haven't found it.

[mark greenman]

LC200N and H1 could both be cool. And certainly would make for a compelling jungle knife.

An 80/20 solution though might be a DLC / PVD coating on the knife, using a tool steel. Other then the very edge of the blade, the rest of the knife would be largely impervious to corrosion.

I also like the laminate of 420j/VG10 used in Fallknivens knives. Thats proven both tough and corrosion resistant, and of course could be made even more so with a DLC/PVD coating. The other advantage here is that there's a proven track record of Japanese made, 6mm thick laminated choppers. There's Fallkniven, as well as Cold Steels 'San Mai' blades like the Trailmaster. However, both designs featuring Convex edges, so I'm not sure how VG10 laminate would fair in terms of a FFG/Hollow grind edge in terms of impact.

[The Meat man]

I don't know, I've seen pictures of an H-1 Rock that got bent from chopping (was it a coconut? )

H-1 is great stuff, but for heavy impact use like chopping, I really question if it has the strength to handle it. Seems like CPM 4V or 3V or even 1095 would handle the stress a lot better than H-1.

[curlyhairedboy]

I also seem to recall a Rock in H1 that had edge deformation due to chopping. A steel that can get harder (Lc200n) seems to hold up better.