Testing Spyderco Mules ZDP189/CPMS35v

[xavierdoc]

So far I only have two of Spyderco's Project Mule knives. For those not in the know, the Mule Team Project was started to allow knife afficionados to compare various steels using a standard blade shape. The blades are covered by Spyderco's warranty but it is up to the purchaser to fit scales.

These were to be hard working knives, so I fitted linen micarta to my two mules. I also reshaped the guard as it is rather long. Both blades arrived very sharp.

CPM-S35v with red linen micarta.

The other is a ZDP189 blade. Following reports of the exceptionally hard blade cracking/breaking, Spyderco announced an optional recall. Their initial plan was that the returned blades (unhandled) would be re-heat treated to a lower Rc (a mere 60-61!?) but subsequent analysis suggested the structure of the steel was at fault not the HT.

In view of the early reports of failures, I chucked on some ugly brown, linen micarta which was hanging around. I went a bit overboard on the rivets, in number and vigorousness of peening (you can see the damage to the micarta!) But this was a rush job for testing only. The blade didn't seem to mind me pounding away at those rivets. Not my best work!

First, some wood:

Whittling an ash stave for a carving horse:

Feather (fuzz) sticks:

I found the CPM-S35v better for feather sticks. I suspect this is simply because I felt enough confidence in the steel to apply a lot of lateral force, allowing tighter, thinner curls. I was probably subconsciously aware that the allegedly very brittle ZDP189 might not like this treatment.


Continued in Part 2...

 

[xavierdoc]

Part 2

Food prep: The blade shape and edge excel at food prep so long as the guard is shortened (it still impinges on the cutting board in some situations):

Hunting:

WARNING: Gory pics linked -Beware!
Two fallow does, post gralloch

The blade shape was fine for the somewhat fiddly release of the rectum and vagina from the pelvic walls (picture). I didn't notice any blunting by the end of my thrid deer that day (3rd deer not shown).

Popping open the atlanto-occipital joints to get the head off.
(Picture)

Taking the legs off is a good test of tip and edge strength, as well as edge-holding: cutting onto bone and sticking the tip into the joint to cut the capsule and ligaments asks a lot of the blade. PictureThe more observant of you will have noticed there are lots of front legs, few back legs and some Roe deer legs in amongst the fallow (I had a total of three deer to process).

Retrieving a bullet that had not exited (I homeload and I like to know the retained mass to tie in with the post-mortem findings and help improve the terminal ballistic performance of my rounds) The knife was still sharp enough to cut through the hair and skin over the bullet.
(Picture)

The pluck showing high heart and lung shot:
(Picture)

Before skinning (picture)

Post skinning/pre-butchering (Picture)


Meanwhile, back at the ranch...

A heavily pregnant mare had jumped into her manger (mad animal!). The girls who run the livery were reluctant to get her to jump out in case she hurt herself. We ended up taking one end of the manger off. This required abuse of lots of tools, including my mule. The heads of the coach bolts had been driven deep into the old railway sleepers and with the time, the wood had swelled, completely covering them. In order to get the impact driver on to the heads, I had to dig out the wood from around them. Inevitably, I ended up hitting the heads with the blade several times :C

Spot the spyderco:

Edge damage from digging out wood from around buried coach-bolt; the edge at the tip has deformed a little with small chip only (quite impressive given the abuse sustained):

I used the knives for cutting some leather (3.5mm veg-tanned). I diced the off cuts, too, and then tested the blades on a piece of paper:

Interestingly, the ZDP was still able to slice curls from the edge (although not very fine curls) whereas the CPM-S35v could not (see top of the sheet in pic above), and tended to snag in simple drag cuts through paper.

Corrosion hasn't been a problem for either blade. I have had no difficulty sharpening with japanese water stones and ceramics. I had expected to need diamond stones for the ZDP189 in its ultra-hard state.

I have tried to balance the use of these two blades to allow a comparison of the steels. On the face of, the ZDP189 seems to exhibit better edge-holding, but in practice I think I worked the CPM-S35v harder, so it blunted more.

In summary:

I like the design of the mule blades, except for the prominent guard (not shown here as I had already ground it down.) I have not tried battoning and I doubt the depth of the blade would lend itself to finer whittling/carving where tight turns are required.

CPM-S35v, like it's S30v sibling, makes for a good blade steel. I suspect I'd be hard pushed to notice a difference between the two, though. It was sharpenable and held a good edge through a range of tasks.

ZDP-189: this test is not really a fair appraisal of ZDP's capabilities, due to the faulty batch (or whatever it was) of steel this knife was made from. My blade has not shown any cracking or chipping, despite moderate use. It lives in the kitchen, where it succeeds as a food prep knife. Time will tell how the steel holds up. I have other knives in ZDP (Stretch CF, Caly3 CF) which I like very much.

I look forward to the next Mule, whatever it turns out to be made of!

 

[JTR357]

:thumbup:Very well thought out,in depth review!Thanks

 

[DennisStrickland]

great realistic review xavierdoc. this a what i call real testing of knives. as i mentioned in past posts the knife testing we are interested in is all about how many whitetail we can process before needing a blade touchup. cardboard cutting gives an idea but in texas its whitetail & hogs.excellent photos along with good handle work. what caliber were you shooting? i used to handload years back but do'nt shoot nearly as much as once i did.also in the 70s factory ammo would hardly do 2 in. at 100 yds. with computers being in the picture i have gotten 3/4 in at 100 meters so that's good enough.i hope we see much more of your posts since so little is as realistic, by the way good photography.thank you

 

[DennisStrickland]

xavierdoc the spyderco enduras in zdp are pretty tuff. although i would'nt pry wood with them i cut ton buns encrusted with mud & strong poly net covering with no chipping. also cutting vines i hit wire hard 3 times & got no dings. the zdp mules have suffered some major cracking problems but the folders are preminum . have a stretch in zdp on way & will wring it out to see if zdp is brittle.if you can find a mule in m4 i think you will be in love.

 

[zyhano]

very cool review, great pics. thanks for sharing

 

[aivonline]

xavierdoc, thanks for a great review.
in the hunting there is only S35V mule in the pics (correct me please if i'm wrong). did you use the ZDP Mule for skinning as well?
any damage to ZDP blade/edge at all?
I have a ZDP Mule myself. I haven't put it through any chores yet, it doesn't have a handle yet and I'm curious to know what Mule's ZDP limits in real-life use are.

 

[xavierdoc]

xavierdoc, thanks for a great review.
in the hunting there is only S35V mule in the pics (correct me please if i'm wrong). did you use the ZDP Mule for skinning as well?
any damage to ZDP blade/edge at all?
I have a ZDP Mule myself. I haven't put it through any chores yet, it doesn't have a handle yet and I'm curious to know what Mule's ZDP limits in real-life use are.

I used the ZDP for skinning and some of the butchering, but I didn't use it for popping joints; no damage incurred. It might have been fine with heavier stuff but I don't think there is anything to prove with this particular ZDP blade -the problems are already known and so I want to keep mine in one piece (working in the kitchen.) It was fine with the wood (ash).

xavierdoc the spyderco enduras in zdp are pretty tuff. although i would'nt pry wood with them i cut ton buns encrusted with mud & strong poly net covering with no chipping. also cutting vines i hit wire hard 3 times & got no dings. the zdp mules have suffered some major cracking problems but the folders are preminum . have a stretch in zdp on way & will wring it out to see if zdp is brittle.if you can find a mule in m4 i think you will be in love.

I have a Stretch CF in ZDP and the Caly3 CF laminated 420J/ZDP . Both excellent knives. The Stretch lives in a kydex neck sheath and sees a lot of use without problems, so far. The Caly 3 just gets looked at for some reason (it begs to be used, though.)

I would certainly like a Mule in M4 (but the list of knives I would like is a long one!)

 

[xavierdoc]

...what caliber were you shooting? i used to handload years back but do'nt shoot nearly as much as once i did.also in the 70s factory ammo would hardly do 2 in. at 100 yds. with computers being in the picture i have gotten 3/4 in at 100 meters so that's good enough.i hope we see much more of your posts since so little is as realistic, by the way good photography.thank you

Rifle was a Tikka T3 Heavy barrelled stainless in .243Win.
Round: 100gr Sierra Gameking over 43.5gr of Vihta Vouri N160, Norma Brass, CCI primers.
Retained mass: This is the first time one of these has failed to exit. I cleaned up the recovered bullet (from the pic above.) Here it is next to a prohunter and a gameking:

Not perfectly clean: 43% wgt retention

I switched to the Gameking after poor penetration and retained mass (40%) of Speer 100gr SPBTs. Pics of a retrieved Speer SPBT 100gr

As you can see, the jacket tended to separate from the core. Not heavy enough construction for the healthy fallow in Sussex!

I've been happy enough with the Gamekings and their cousins the Prohunter. This was the first fail to exit (deer dropped fine, though.)

On chrono, they are ticking along at just under 3000fps (I don't chase velocity per se, going for accuracy and "enough" downrange energy.) Predicted velocity was over 3000fps. The accuracy is excellent for a more-or-less stock rifle: sub 1" at 185yds -the maximium my local range can offer (the range is only 10mins from my house so load dev is a breeze!)

My other favourite calibre for deer is .308Win (Sako 75 Heavy barrelled stainless, laminated stock), which is even more accurate and has no penetration problems with the size of animal I encounter here. This gun is remarkably accurate with homeloads -I won a Silver in the McQueen at the annual Bisley Phoenix comp a few years ago (50 ex50 but lost on the V bull count.)

If I miss something, it'll be my fault!

 

[DennisStrickland]

xzavierdoc thans for the excellent pics. i used to load sierra 85 grain b.t.h.p. over 46 grains of win. ball [760] i think. the m4 mule is really hard to find since my brother has been looking for another 6 months. i switched to 270 after my 243 blew up on a turkey backbone. your choice of cutlery compliments your taste in long guns.