Custom serrations...

REK Knives

REK Knives

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Knifemaker / Craftsman / Service Provider
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Apr 3, 2011
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so i'm getting ready to experiment around with doing custom serrations on my becker bk2 and figured you all may be interested. i could not find a lot on the net about doing this, so this will be more of an experiment :D if any of you have seen the CRKT Tighe series knives, those are the serrations I want to do. i think the way they are designed that they would desimate anything they cut through. i am wanting to do it slightly different however in 2 ways... 1. i want to put the serrations on the half of blade near the tip instead of the heel. 2. i want the serrations to come to a point in the center of the edge instead of the typical chisel grind.

here is a pic of the type of serrations i want to do. anyone have any esperience w/ this? i'm gonna get some pieces of scrap metal to experiment on 1st :)

CRKTMiniMyTighe.jpg
 
Well, I'd think it would be possible enough... Definitely want to use a fixture and do some layout first, and you're going to need one hella tough grinding medium, maybe a very coarse diamond rod?

I'll be interested in seeing how this comes out! Those serrations even look large enough that they wouldn't be as bad to sharpen as some.
 
yeah, gonna definitely practice on some other metal first... gonna use a trick i read about here to at least start the serrations before going to grinding tools. taping one round file to another so that way they are all evenly spaced when you start them :D will definetly be a weird angle though.
 
Sweet guys! I had no idea what they were called... Thats good to know. Now I just gotta figure out how to do it. Gonna play around with it this weekend. I'll keep you posted!
 
I have used chainsaw files to make my own serrations a few times ,they are super agressive; I am not sure but you would want 3/8 or so to make that type of serration. I have one word of warning take care as you are pushing toward the edge of the knife.
 
ok so here's what i've done so far... wanted to experiment around with another knife before i tried to remove THAT MUCH steel off of the becker. so i first tried a chain saw file.... didn't do much AT ALL to the edge... wouldn't remove hardly any metal. i have heard that the files are heat treated to about the same rockwell leve that blades are, so they don't do much good.

so i ended up using a dremel tool, using a wet rag to keep the temper from being damaged. here's what i have so far... the serrations need to be evened out a little bit, but it has turned out nicely so far!

veff%2525202.jpg


Veff%2525201.jpg


one of the things i did was serrate it on both side so i don't have a chisel grind. i have read that the chisel grind veff serrations are typically week when used. so these should be much stronger.
 
Nice work, my own home made serrations looked so uneven I never tried more than twice. One word of caution, grinding the serration into both sides will produce a very obtuse edge angle that will make a difference in use. Much tougher, but less effective.
 
HeavyHanded said:
Nice work, my own home made serrations looked so uneven I never tried more than twice. One word of caution, grinding the serration into both sides will produce a very obtuse edge angle that will make a difference in use. Much tougher, but less effective.
Click to expand...

yeah, you're probably right... i think the trade off is well worth it though. if you broke one of those tooths off, you would wish you had made it steeper! but it still cuts like a champ.. i'm playin around w/ it now to see how i like 1. the veff serrations, and 2. the serrations at the end of the blade.
 
Well, and you could always just decrease the angle on the side of the serration... I'd start to be a tad afraid of severely weakening the blade there, though, I guess. Hmm... I'm definitely interested in hearing how the serrations at the front work out for you, I don't think I've ever seen that before.
 
how cutting them into both sides change how obtuse you decide to grind it ? sounds like the very same misconception than when people say a chisel grind is thinner because it's ground on one side only.
 
Well, cutting the same serration in from both sides will result in a deeper 'gullet' and a corresponding angle change, compared to grinding the same gullet depth solely from one side. Instead of, say, 20 degrees inclusive (one side, meeting a vertical plane) you end up with 40 degrees inclusive (both sides ground in at 20 degrees). As I was ruminating, you could just make that a 10DPS angle, but that would result in the serration going very far up the side of the blade. The angles I chose here are pulled out of thin air for discussion, obviously, a 20-degree serration would be a tad fragile. :D
 
yes but if you're sharpening a knife for a given use to 30° inclusive or 15°/15° because it suits your needs in term of toughness and want to convert this knife to a chisel edge it sounds pretty obvious that you'll grind the chisel edge to 30°/0° not 15°/0° .... it's inherent to chisel ground.

same issue here, if proper chisel ground serrations are ground at .... say 60°/0° chisel, you have to grind them 30°/30° if you want them aligned and if you want them to perform the same ... going 60°/60° would be pretty stupid ...

and yes given the same thickness before sharpening, an edge ground 30/30 will have thinner bevels on both sides than the single bevel ground at 60 on only one side, because you remove stock from both side to achieve an edge ...

just my view of the problem.
 
I think we're both on the same track here, actually. My thought being that if you actually ground it that thin, using either method, the blade is going to become very thin due to the extended distance up the side of the blade that the removed cylinder of material would take out. I believe the overall statement was made because the serrations appear to have about the same edge distance from peek of the edge to the start of the primary bevel as the edge itself, despite the thicker blade in the top area of the serration.
 
in fact this was the sentence i reacted to. i should have quoted. sorry :D

HeavyHanded said:
One word of caution, grinding the serration into both sides will produce a very obtuse edge angle that will make a difference in use. Much tougher, but less effective.
Click to expand...

i thought this made no sense as when grinding both sides you can either make the serrations thinner or more obtuse ... and here judging the bevel width where it connects to the plain edge, it looks like he matched the angle pretty well ... at least more accurately than i think i would be able to do with a dremel.
 
Oh, I took that comment to mean that taking a standard set of serrations and grinding a matching angle on the other side would result in a very obtuse angle. Which it would.

Yeah, there's no reason that a set of bevels ground the same as the edge would produce a different angle. And I agree, I'm glad it wasn't ME trying to do that. There'd be gouges and horribly asymetric serrations all over that blade. :D
 
Ok guys... here you go. I may have ground them too steep, but overall i think they turned out pretty nicely!

Before:
C360_2011-03-30%25252021-58-28.jpg


After:
2011-07-19%25252015.03.11.jpg


2011-07-19%25252015.05.40.jpg


i went real slowly and was very careful not to let the blade heat up too much...actually made a vid :D what do you guys think?
 
Komitadjie said:
Oh, I took that comment to mean that taking a standard set of serrations and grinding a matching angle on the other side would result in a very obtuse angle. Which it would.

Yeah, there's no reason that a set of bevels ground the same as the edge would produce a different angle. And I agree, I'm glad it wasn't ME trying to do that. There'd be gouges and horribly asymetric serrations all over that blade. :D
Click to expand...


That's what I meant, and I agree with your statement - trying to match the existing bevel when cutting serrations into both sides will put the grind path way up into the face of the blade. There's a reason very few Mfgs attempt it, and it isn't just for the increased tooling.
 
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