Re-beveling a Kershaw Launch 4 from 28.5 to 22 degrees

[Djrichone]

I just got a new Kershaw Launch 4, a California legal auto. The problem is the bevel is uneven. I put it on my KME sharpener and with the sharpie and angle finder on my iPhone I found the bevel to be around 28.5 on one side and 27.8 on another. The variance in degrees doesn't bother me as much as the degree of the bevel. I thought 18-22 degrees were the norm for Kershaws per their info on their website. 27 and above seems too obtuse for me.
Either way I matched the angle and am unhappy with the performance of the blade. I want to re-bevel it to 22 degrees but am concerned on taking too much steel off. I have the equipment to do this, but I wanted some of your opinions on going down 6 degrees on the existing bevels.
I could send it to Kershaw, but I feel I can get a better edge.
So, am I cool re-beveling from 28.5 to 22 on a new blade? Anything I should be careful for?
Thanks for reading and your responses.

 

[cbwx34]

I just got a new Kershaw Launch 4, a California legal auto. The problem is the bevel is uneven. I put it on my KME sharpener and with the sharpie and angle finder on my iPhone I found the bevel to be around 28.5 on one side and 27.8 on another. The variance in degrees doesn't bother me as much as the degree of the bevel. I thought 18-22 degrees were the norm for Kershaws per their info on their website. 27 and above seems too obtuse for me.
Either way I matched the angle and am unhappy with the performance of the blade. I want to re-bevel it to 22 degrees but am concerned on taking too much steel off. I have the equipment to do this, but I wanted some of your opinions on going down 6 degrees on the existing bevels.
I could send it to Kershaw, but I feel I can get a better edge.
So, am I cool re-beveling from 28.5 to 22 on a new blade? Anything I should be careful for?
Thanks for reading and your responses.

Shouldn't be an issue... I usually reprofile knives to 18 deg. or less (as do many in the forum). Not much to worry about... just check your work as you go, keep the bevels even, (don't overgrind one side), be careful around the tip, etc. (I'm guessing that you probably already know this, just from what you already know in your post).

p.s. Sending it back to Kershaw wouldn't guarantee any better result... they're resharpened the same way as the initial job as near as I can tell. So, yeah, you can get a better edge... plus it will be setup for how you sharpen/touch up the blade. :thumbup:

 

[Rey HRH]

6 degrees isn't such a big thing. I've done several of my ZTs to 14 degrees from what I believe are 25 degrees from the factory. Some even go down to 10 or even do a full flat grind. It sure is a lot easier to do with a belt though. Either way, start with the coarsest grit.

Things to watch out for is near the bolster. I found factory knives aren't so precise near this area so you might have to take a lot more time near this spot than what you'd expect.

And if you want to keep the knife pristine, I suppose you can tape up the surfaces that you don't want to scratch.

And since it's a CA auto being 2", I think you want to be careful to keep any debris out of the mechanism, right? I don't know how difficult it would be to take the knife afterwards to clean it.

 

[Jason B.]

Stay below 20 DPS/40 inclusive, anything over 40 inclusive is a waste of time and effort.

 

[Djrichone]

Stay below 20 DPS/40 inclusive, anything over 40 inclusive is a waste of time and effort.

That was my assumption too, I was just concerned with the amount I would have to take off. Ill definitely do 20DPS/40 inclusive or maybe even 18DPS/36 inclusive.

Yeah, the blade is ground uneven so it will take some work. Hopefully the 100 grit diamond will make it somewhat faster.
Oh, and I'm definately more careful with my tips. Learned the hard way

Thanks for the quick replies and suggestions guys!

 

[Gaston444]

Kershaw edges are horrible. 28 degrees on a folder doesn't surprise me from them...

The whole issue of taking down the angle depends on whether or not the blade has a hollow grind or not.

If the surface above the edge is hollow ground, it will go down to 12 per side, as on mine below, with no problem.

If it is flat ground, as on the Al Mar above it, then you are in for a world of hurt keeping the knife looking good (as I obviously failed to do free hand): My AL Mar has been sent for re-finishing by a pro, probably to a zero edge or something useable...

Re-profiling on a hollow grind is like day and night compared to any flat or convex grind... That is the main issue when re-profiling.

Gaston

 

[HeavyHanded]

Kershaw edges are horrible. 28 degrees on a folder doesn't surprise me from them...

The whole issue of taking down the angle depends on whether or not the blade has a hollow grind or not.

If the surface above the edge is hollow ground, it will go down to 12 per side, as on mine below, with no problem.

If it is flat ground, as on the Al Mar above it, then you are in for a world of hurt keeping the knife looking good (as I obviously failed to do free hand): My AL Mar has been sent for re-finishing by a pro, probably to a zero edge or something useable...

Re-profiling on a hollow grind is like day and night compared to any flat or convex grind... That is the main issue when re-profiling.

Gaston

As the edge grind gets wider its going to show every unevenness in the primary - really for the amount removed it looks pretty good. At some point it just winds up being easier/nicer to regrind the primary but also a real bear to do freehand.

Edit to add: this is also where where a full or high grind convex comes in handy...

 

[smith357]

Kershaw edges are horrible. 28 degrees on a folder doesn't surprise me from them...

I knew there was a reason why. I picked up a Link to use for a work knife and $35 for a US made knife made it a no brainer. The only thing I did not care for was the edge, but then the only factory knife that ever satisfied me out of the box was my Bark River. I used the Link one day, and reprofiled the edge as soon as I got home from work. I prefer convex edges so that is what it sports now, I could not tell you the angle, but it is a lot more acute than it came from the factory. The next time it needs sharpened I'll take it a tad farther.

 

[Petunia D. Feeble]

They're done by hand on a belt grinder I'd bet and like me, the individuals doing them have good days and bad days apparently. I've hade two Links that were almost dead even side to side and a third with an 11 degree swing. Dice roll really.

At least the Launch is pretty even. Given the blade shape and primary grind, the steep angle doesn't really surprised me. Shouldn't lobe a problem for the KME. With the coated blades though I tend to stay away from low grit stones. Leaves a cleaner line at the bevel.

Edit: My grinding talent has good days and bad days. I don't sharpen on a belt though. Customers are safe.

 

[Djrichone]

Ok guys, so I re-beveled and it wasn't as bad as I anticipated. I set my angle to 18 DPS and went to town with the 100 grit on the KME. It probably took about an hour to hour and a half to go all the way up to my 1500 diamond. Overall I'm happy with the result except for the tip. I was too careful not to round it so it still needs a bit more to get it the way I like. The part by the choil also needs some more grinding to get the bevel even. Maybe Im being way to picky at this point, but this KME system has opened my eyes to what a perfect bevel should be.
The blade is hair popping sharp like I like it