Convex edge on a sebbie?

giant1

giant1

Joined
May 9, 2007
Messages
2,955
I currently use a combination of the Spyderco sharp maker and a leather strop to keep my sebbie sharp. I mainly use the strop as I never really let the edge go off.

I am wondering if it would be better to put a full convex edge on the blade instead by using a mouse pad and wet and dry. Not really knowing anything about sharpening I thought I would ask to see if anyone here has done this before I go ahead and do it myself.

I guess if I do this the sharp maker would be useless as far as my sebbie goes? I would then use the mouse pad and wet & dry for future sharpening and the strop to maintain / polish the edge.

Has anyone done this?
Was it a good idea?

I would appreciate comments and advice from anyone that has gone down this path

Thanks
Frank
 
Iv not done it with a Seb. but I have done it to a few other knives.

You do need to be carefull doing that with a hollow gound blade though. I ended up having to flat grind my Spyderco jester when I gave that a convex edge.
That jester is now one of my sharpest knives though so it was worth it. Luckly its a really small blade so it wasnt much work. :)

The other knives iv done were flat ground any way so it was much easier to do. :thumbup:
 
Thanks Haze

So do I read into your post that hollow grind blades would not normally have a convex edge?
 
Giant1---Haze will know the answer to your question but I'd ask the Master, Tom Krein, also.
 
I'm not sure exactly what is meant by putting a convex edge on a hollow ground blade. But, I used sandpaper (80-1000grit) and a trigonometry textbook on my small Classic to completely round off the corners. I'd say that's about as convex as I could get it. And my goal was to make it as convex as possible, although, obviously, making it completely convex (a la fallkniven) is impossible. Now I just keep it sharp with course, fine and ultra-fine DMT diamond "stones". I am very happy with the result. Makes for a very nice cutter of everything from arm hair to wood. :)
 
giant1 said:
Thanks Haze

So do I read into your post that hollow grind blades would not normally have a convex edge?
Click to expand...

Usually you see convex edges on flatground blades but you can do it on hollow ground blades.

This is a pic of my jester, you can see a line down the middle of the blade. That is whats left of the hollow grind after "flatening" it out.
Its not a big deal on a knife like that but on a Seb. it would be something that annoyed me.

attachment.php

It looks like it has a bevel in the pic but its just the polished edge showing up against the scratched flats.

If like Brian6244 your carefull and just remove material form the edge bevel area you should be fine.

You could just contact Tom Krein for a regrind, he really, really knows his stuff. Its not expensive at all and your knife will cut like a chainsaw :eek:


:thumbup:
 

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Haze

I live in Sydney Australia so I don't want to tempt fate by sending a knife overseas on a round trip unless I really have to :) so I will learn how to do it myself even though I will more than likely never be in Tom Kreins league.

I have been reading a lot of stuff on the net lately just trying to educate myself about sharpening and it seems like most people agree that a convex edge is the way to go on most blades. The more I think about it, the more I wonder whether this also holds true for a hollow grind.

I'm very happy with the edge that I get using my sharp maker and leather strop. I guess I'm asking how can I make it better.

My reason for posting here was because I wanted to know if anyone with a Sebbie has changed the original bevel edge to a convex one.
 
I had a blade sent to Tom from here in Tawian, the whole thing only took about 2 weeks.

All grinds have pros and cons depending on what your doing with the blade but generally i think a convex edge is indeed the way forward. :thumbup:

Give it a whirle and see how you get on, if you do end up just goosing it up you can always give Tom or someone similar a shout ;)

:):thumbup:
 
There is a LOT of meat in the sebbie edge to play with. It really lends itself to a convex job. S30V according to some really benefits from a highly polished edge.
 
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kdizzog6 said:
I convexed my seb. I love it! Scary sharp and easy to keep it that way.
Click to expand...


Justabuyer said:
There is a LOT of meat in the sebbie edge to play with. It really lends itself to a convex job. S30V according to some really benefits from a highly polished edge.
Click to expand...

Thank you to both of you for posting your photos. Good to see a Sebbie being used. I love using mine as much as possible.

How did you guys get the convex edge on the blade. Just using a mouse pad and wet & dry??
 
Nope... I roughed mine in on a diamond stone then smoothed it out on some leather wrapped in sandpaper. Then stropped on leather with green compound.
 
Justabuyer said:
Nope... I roughed mine in on a diamond stone then smoothed it out on some leather wrapped in sandpaper. Then stropped on leather with green compound.
Click to expand...

Did you have to use the stone to get the bevel down? I'm thinking I should be able to get it down with course Wet & dry (say 200). What do you reckon?

Being a total novice I don't want to attack the blade with a stone and end up making a mess of it. (Although as I type this I think I will get one of my spydies with a convex edge and a practice run on that one first :D)
 
giant1 said:
Did you have to use the stone to get the bevel down? I'm thinking I should be able to get it down with course Wet & dry (say 200). What do you reckon?

Being a total novice I don't want to attack the blade with a stone and end up making a mess of it. (Although as I type this I think I will get one of my spydies with a convex edge and a practice run on that one first :D)
Click to expand...

Here is the thing... If you go with course paper on a soft surface, close enough to the spine to do yourself any good, you will scratch the crap out of the blade.

Knocking the edge back first on a stone lets you do it a bit cleaner. No big deal either way. There is no right or wrong. Soon you will come to realize there is no spoon. :D
 
Justabuyer said:
Here is the thing... If you go with course paper on a soft surface, close enough to the spine to do yourself any good, you will scratch the crap out of the blade.

Knocking the edge back first on a stone lets you do it a bit cleaner. No big deal either way. There is no right or wrong. Soon you will come to realize there is no spoon. :D
Click to expand...


WHAT!!!! No spoon :eek: :eek: :D

OK I see what you mean about the stone. I'll pull out the sacraficial knife and proceed to either destroy it or learn something.

I'll post an update and some pics when I've done it.

Thanks for your advice :thumbup:
 
giant1 said:
Thank you to both of you for posting your photos. Good to see a Sebbie being used. I love using mine as much as possible.

How did you guys get the convex edge on the blade. Just using a mouse pad and wet & dry??
Click to expand...

First I thinned the edge on my edge pro, then the mouse pad and, 400, 600, 800, 1500, 2000. Then stropping. Its thinned out pretty good. Now a quick stropping eveynow and then, hair will pop right off my arm.
 
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kdizzog6 said:
First I thinned the edge on my edge pro, then the mouse pad and, 400, 600, 800, 1500, 2000. Then stropping. Its thinned out pretty good. Now a quick stropping eveynow and then, hair will pop right off my arm.
Click to expand...

Thanks kdizzog6

Sounds pretty much the same technique as Justabuyer except a little different in the materials / tools used.

I've got a little spyderco that I will practice on before I have a go at the Sebbie.

I'll let you know how it goes.
 
Hi Guys

I hate posting this but can't seem to find a answer for my question, but what is a convex edge and how is it made on a knife?
 
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1. Hollow grind

2.Flat grind

3.saber grind

4.Chisel gind

5.Double bevel

6.Convex
 

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