Looking for a tuturial for convexing my knife.

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rc3mil

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Title pretty much sums it up. I am going to try convexing my RC3. I have no idea how to even begin this process. If anyone has a link to a good tutorial on how to do this or would like to share there own experiences, that would be great. Wet/Dry? Grits? How? Pressure? Everything and anything.

A detailed explanation would be greatly appreciated.

Thanks in advance.
 
It would be a waste of time, the blade is too thin for it to even be worth it.
 
230grains said:
There's nothing wrong with convexing the edge, if only for ease of sharpening.
Click to expand...


True but the edge on that knife is very thin to begin with, if convexed in the wrong way it could lead to massive edge deformations and chipping.

Not all that long ago convex was not thought of that much but now it seems like everyone wants everything convex. Convex has its place but with some blades its a useless waste of time, for convex to be effective and practical the blade must have some thickness. If the blade is too thin then your defeating the propose of convex.
 
Hi knifenut,

I have seen pictures of the beautiful edges that you apply to knives, can you help me by defining the purpose of the convex edge for us and relating it again to this situation where the edge is thin?

I have only convexed my axes and a Yellow scaled Ranger three blade traditional pocket knife with very thin blades. The Ranger was the very first hand convex edge I applied to any non-chopping tool the rest were with a belt sander. The Ranger was the sharpest edge I had personally created which had a lovely wet looking edge and easily tree topped my arm hair.

Thank you in advance,

Doug
 
Think of a BRKT, how many are 1/8in< stock? How many are as thin as a RC3?


Convex is all about the shape and having enough thickness for that shape to be effective. If you ever use a thick convex blade you will see that even though it may be 1/4in thick it cuts like a much thinner blade and even when dull still cuts like a sharp knife. Everyone seems to have gone convex crazy around here in the past few months wanting everything convex without understanding it place or its benefits.

You can convex anything you want but how much is it really doing for you? If you can sharpen to 10 degrees per side and your edge bevel is 1.5mm or less then your probably not going to benefit from a convex sharpening.
 
Hi knifenut,

I have three BRKT knives that I do not really use much and have not had to sharpen, but all are the small or micro variety. They are thicker than the Ranger three blade slip joint that I sharpened. I will make an effort to use them a bit more to try and see/feel what you are talking about.

Thanks again for the extra info.

Doug
 
Nice vids. Exactly what im looking for. My axe could do some rebuilding the convex. Flattened it a bit in the past trying to sharpen it. It got decent sharpness for an axe but it has seen better days.
Picked up some 30x30xm sheets of 400, 600 and 1000 gritt. Curious to see how it works out.
 
So i've spend about 2.5h sharpening my new kukri.
First the 400gritt than 600 and finally 1000 gritt. The last 1.5h or so was at the 1000. It has a decent edge now, i can feel it bite when attempting to shave my arm and takes of a hair or 2, but not really hair-popping. Is this as close i will get it with a 1000 gritt?
 
basb said:
So i've spend about 2.5h sharpening my new kukri.
First the 400gritt than 600 and finally 1000 gritt. The last 1.5h or so was at the 1000. It has a decent edge now, i can feel it bite when attempting to shave my arm and takes of a hair or 2, but not really hair-popping. Is this as close i will get it with a 1000 gritt?
Click to expand...


If you were making it convex then you probably needed to start with 220 grit or even as low as 80 grit. 400 grit is fairly fine and you should be shaving sharp before moving to the 600 grit. 1000 grit should be clean shaving to hair popping by the end of its use.
 
So let me see. Start out on very course sandpaper and kinda lightly draw the knife in a stropping motion until you get a burr then flip the blade, repeat then change grits? How much pressure?

This question is in regard to changing a V grind edge to a convex
 
rc3mil said:
So let me see. Start out on very course sandpaper and kinda lightly draw the knife in a stropping motion until you get a burr then flip the blade, repeat then change grits? How much pressure?

This question is in regard to changing a V grind edge to a convex
Click to expand...

Do a single pass per side until the edge is formed, don't worry about the burr until your convex shape has been applied to the blade. Once the shape is in place then you can work on the edge. How much pressure will be determined by the blade and how much convex shape you want.
 
knifenut1013 said:
If you were making it convex then you probably needed to start with 220 grit or even as low as 80 grit. 400 grit is fairly fine and you should be shaving sharp before moving to the 600 grit. 1000 grit should be clean shaving to hair popping by the end of its use.
Click to expand...

Will get some more sandpaper than, its cheap as hell for 0.30 bucks a sheet. Not the metal sort i think though, coming from a DIY shop it seems ment for wood.

I was under the notion that the kuk was already convexed. Looks that way and it sounds logical for a chopper.
 
I followed the tutorial and tried convexing my Persistence and it's coming along quite well. Opted not to force myself to do everything in one try but I'm liking how the edge is developing.
 
You can't use just one grit unless your doing a touch-up. It would take forever to form a bevel with just one grit unless its very coarse like 220 but then it wouldn't be that sharp either.
 
I started to convex my V-10 FFG Endura. I see a good shape but it's not sharp. I have a mousepad and I started with 400 grit then moved to 1000 grit. I can't get it to cut paper easily after the 1000. Should it be cutting paper before I go to the 1000?
What am I doing wrong?
 
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