Bush Sword WIP 36in CPM 3V

Huntsman Knife Co.

Knifemaker / Craftsman / Service Provider
Joined
Sep 10, 2010
Messages
3,304
So here's my latest project. This is an order for a customer. I've been wanting to make a blade like this for years but never had the time to get around to. The original plan for this blade was S7 and micarta, but we decided to go all out and step it up to 3V and Terotuf. Getting to make a sword like this is a dream come true for me and I can't wait to see how it turns out.

I apologize in advance for the crappy pictures. My phone doesn't have a very good camera and I don't feel comfortable taking my Mark III 5D into the shop. There will be some good pictures when its finished.

It all started with a CAD sketch. Made a few modifications for the customer and then got it cut at the water jet.

Screen%20Shot%202015-02-19%20at%203.32.35%20PM_zpscpewqhfn.png


She has arrived!

I came home last friday to a massive piece of .180 CPM 3V waiting for me on my porch.

I wasted no time and went straight for the dykem. Also got in a sweet sheet of orange Terotuf. I'f you've never used terotuf, its hands down the best material out there for hard use knives. Its crazy grippy and tougher than G10. Ill be making it a permanent handle option on all my blades.

20150515_131356_zpsfgfvyddh.jpg


20150519_225517_zpsje1ssss3.jpg


Being the mad man that I am, I decided to hard grind the blade. CPM 3V at 60RC is a bear to grind even in a 5in knife...a 25 inch bevel is a whole new level of pain. So I began chipping away. This thing chewed up and spit out 36 grit Cermaic cubitron belts like they were nothing.

I like to scribe in center lines and then set the initial bevel on a 10in wheel with an old belt. Here she is with the bevel set and ready to hit the flat platen.

20150517_235749%201_zpsvqqthqtl.jpg


After about two hours of grinding the bevels begin to really take shape. The recurve presents a few challenges but after a few passes I got the motion dow. I had to run my grinder at full speed and use high pressure to remove any steel even with a fresh belt. Definitely won't be hard grinding one of these again. I take the grind to where the balance feels good and then stop.

Also, I really need to clean my shop. I promise its not that bad all the time. Ok, its that bad most of the time. But when you get in the zone stuff gets messed up.

20150518_004153_zps9hnwoi0a.jpg
 
Last edited:
Here she is with the bevels roughed in and finished to about 120 grit or so. Now comes the fun part, finishing the flats.

20150518_022131_zpsx8gn2bj1.jpg
 
That's very cool Hunter. Nice job taking on the project. Also, what is your email?
 
What the heck do you do with a 3V sword?? I want one! :D

Anything you want I suppose :D Its without a doubt the most powerful blade I've ever held. Not that I have any experience with this (nor hope to) but I'm 100% certain you could lop a mans leg off in one stroke with this thing. If nothing else, holding it makes you feel like a kid playing with a lightsaber again.

That's very cool Hunter. Nice job taking on the project. Also, what is your email?

Hey Camber, its huntsmanknifeco AT gmail DOT com
 
Ok so here's an update. I just finished grinding last night and I'm doing handles today. Finishing the flats was an absolute nightmare. First I tried surface grinding them with my awesome Travis Wuertz surface grinding attachment, but this blade is so long and flexible that I couldn't get an even finish. I then had to go to the platen and grind the flats by hand. This took about 4 hours and was a very frustrating process. In the future, I will probably just use non precision ground steel and leave the flats unfinished like I see alot of other guys doing.

This piece is no beauty queen, but on the budget its being built, it was never meant to be.

Here's a couple pics I took this morning. This is finished out at 280 grit and then hit with a cork belt. The bevels turned out pretty well. They are even and while there's a few small imperfections, for a 25in recurved bevel, I think they look pretty good. As for the flats, they look OK but have some scratches and imperfections but at the end of the day I'm very happy with how the blade has turned out. I might hit the flats again with a 320 grit belt but at this point I think they are about as good as they can get. Having a disc sander would have been a big help during this process but I opted to purchased a surface grinder instead.

I took the edge down to .008 before sharpening. This is the thinnest I've ever taken a big blade and I'm excited to see how it does. I take all my 3V knives this thin or even thinner before sharpening and they hold up to batoning and everything just fine so this edge should still be very durable even with it being very thin.

20150520_135550_zpstdvfw0eq.jpg

20150520_135340_zpsi1yohqh2.jpg


This angle allows you to see more of the flaws on the flats. Some 180 grit scratches are there and theres a few areas with a bit of unevenness but theres not alot you can do.

20150520_135506_zpsye9pmwwi.jpg
 
Last edited:
Well this one has ended in tragedy.

I did some rough shaping and temporarily attached the handles to do some testing. Day 1, this thing performed even better than I hoped it would. It destroyed everything in its path with ease. Where it really excelled was brush and small diameter trees. It completely sailed through both like they weren't even there. For some harder use testing, I chopped an old locust fence post and while it didn't do much to the fence post, the edge was undamaged and would still shave afterwards. After 1 day I was really happy with its performance but decided to take it out again for a little more chopping.

Here's where it all went downhill. I was taking out a few small 6-8in diameter trees and was really getting comfortable with my strokes and swinging about as hard as I could. I chopped into one of the trees at an angle and ended up hitting a huge knot that was hidden within the tree. When I pulled the blade out and saw the damage I was crushed. The pressure from the softer surrounding wood wrapped the edge around the knot and caused a huge roll. Needless to say I simply ground this blade too thin for the power you can generate with a two handed swing. The sword is effectively ruined and I'll be starting on another one shortly. Gotta just learn from the mistakes and keep moving forward.

But all in all, I couldn't be happier with the performance of this blade. Its a complete monster and with the exception of the rolled edge was impressively tough. It flexes really well and the edge will still shave even after all its been through. With a thicker grind this sword is going to be just killer. In the mean time, I'm going to test this blade to destruction and see what its really capable of when pushed to the limit.


7V0A7198_zpsv6ydhkpg.jpg


A little flexing. It can flex way more than this but I had a hard time getting a picture of it.

7V0A7208_zpsrcrbeqvy.jpg


20150611_200526_zpsqqr5mxbq.jpg


She bites DEEP.

20150611_200235_zpseeymsmtz.jpg


Cue the tears. Here's the nasty roll that send this beast into retirement.

20150611_210603_zps0da1djr8.jpg
 
This kind of sharing is really appreciated Hunter. Makers who do this kind of testing with their products is the type of maker people who are looking for users should support. A maker should be able to give you a pretty good idea of how their blade will perform...and where it will fail. If not, offering a warranty is somewhat problematic...as the maker doesn't even know what it may cover.

As a side note, I notice the apex itself appears undamaged. As you go testing it further, try lowering the angle of the apex bevel. When the damage passes the apex (without hurting it) and ripples the primary the angle of the apex is often too high...the apex is so strong it has to transfer the force to a weaker point. If you lower it the apex should damage first and give you a sign of when you're pushing it too far...and the apex is much easier to fix than the primary :) It also may just in general minimize damage as being thinner it may not generate as much resistance.

(As an aside, I didn't come up with that idea...it seemed completely counterintutive to me, but it worked on my CS Gurhka Kukri. I rippled the primary just like that and since lowering the edge angle I haven't had any issues.).
 
Camber,

I think you are completely correct in your ideas concerning the apex. I will implement it in the next iteration of this blade.

My main issue with taking this one too thin probably happened when I was convexing it. Because this stuff is so hard to finish I think I ended up taking off too much steel before convexing because I was worried if I left it too thick and had to re grind it, finishing it from 50 grit back up to 320 again would have been the death of me. Next time I'm going to leave alot more steel there before the convexing process and end with twice the edge thickness before sharpening.
 
That sounds like a solid plan Hunter. I know edge stiffness increases exponentially (cubically I think) as thickness increases. So an edge twice as thick (even if it's .012 to .024) should be significantly stronger.
 
Wait, so for example an edge .024 should be 4X as stiff as an edge @ .12, does it really need to be that tough? and if so, i wonder what you will give up in terms of cutting performance? the best cutters i have seem to have a small "apex", and even better are the ones with a "zero", non-secondary-ground blades, like a traditional katana for example. would doing away with the 2nd-ary grind and grinding a convex edge with similar edge geometry to a blade with a larger, steeper secondary grind have similar performance? or even improved cutting with an even tougher (the edge itself being convex vs. secondary flat-ground) profile? I would love to see the performance characteristics of the original thinly-ground blade preserved, you know? Thanks - Rad sword, dude!
 
A very nice blade master huntsman. Tell me, how many purses must I pick so that I may, myself, own such a fine implement?
 
What would the price range be on some thing
Like this ? ... also any updates on this blade ?

Frank
 
What would the price range be on some thing
Like this ? ... also any updates on this blade ?

Frank

This blade would fall in the $800+ range. Right now I'm focusing my attention on a Wakizashi Ill be making this summer so I don't know if or when I will have more of these available.

As for the fate of this sword, its currently at my shop in the junk blades pile. I want to fix it one day but it will require a big regrind and some hammering to fix the damage.
 
I have a design for a wakizashi
That I want to get made I saw
That you are once again taking
Custom orders so would you have
Any interest in seeing the design
If so let me know thanks for your time

Frank
 
I have a design for a wakizashi
That I want to get made I saw
That you are once again taking
Custom orders so would you have
Any interest in seeing the design
If so let me know thanks for your time

Frank

Frank,

I no longer do true custom designs except for a few of my long time customers that I collaborate with from time to time. I will be making the wakizashi shown in the other thread this summer. Thanks for your interest. I wish I still had the time to do true custom work.
 
This is a beautiful blade, and at $800, it's not quite to the nosebleed altitude of the $1k+ blades. I like the recurve. Everything about this blade looks practical and useful, for all the myriad uses a blade with this shape can be used for. I hope it gets made again in the future, in any steel.
 
The thought just crossed my mind that this blade might be the two-handed machete I've been fantasizing about lately. It would probably work very nice paired with a smaller 12 inch version with the exact same shape. If you skip the regrind, how difficult would it be to simply hammer out the roll and call it good, for a discounted refurbished blade? I'm not sure I would be able to afford even when discounted, but maybe testing it to destruction would be a waste of a nice blade design.
 
Back
Top