Dual grind/hollow grind question

[REK Knives]

Hey guys... wondering if some of you all can help me out. when I do a hollow to flat transition sometimes the hollow comes out looking more pointy instead of the nice gentle ark from the grind line start to the edge. This is what I mean:​

I want something more like this:

Any ideas/tips? Do I just need to work that transition w/ different pressure applied at the top and bottom of the hollow grind to widen it out instead of just keeping my hand steady?​

​

 

[AVigil]

Grind the tip first and then walk the hollow into where you want it.

 

[Jesse Latham]

Use a larger diameter wheel.

 

[REK Knives]

Grind the tip first and then walk the hollow into where you want it.

Not sure exactly what you mean here and how this would help... any ideas why it is acting like this? If I grind the tip last how does that affect the shape? Thanks for your suggestion!

Use a larger diameter wheel.

I don't think that's the problem... It seems to be an issue whether using a large or small wheel. On the knife in question it was a 10" wheel. On the rest of the hollow grind I'm getting an even arc.

It's weird... doesn't happen all the time, for instance, I did this one the same way as far as I know:

 

[Varga Knives]

FWIW- I've never done a regrind but it looks like when you are running into that problem the blades original thickness wasn't thick enough to support the transition you are working towards at the tip. I think with that top picture you could run the hollow more toward the tip to get the straighter transition but I'm not sure how good it will look.

 

[kindasharp]

You might want to pick up a few Chinese clones to practice on, learning to regrind a new profile on high dollar folders can get mighty expensive!

 

[Rapt_up]

Its the "angle" of the tip that you're flat grinding... If its long and tapered it gives that more "pointed" transition. If its in a thicker more "blunt" grind then its gives the rounder look. At least that's what happens when I model this type of transition in 3D CAD. (I just basically said what Vargas Knives did but its right.)

 

[REK Knives]

FWIW- I've never done a regrind but it looks like when you are running into that problem the blades original thickness wasn't thick enough to support the transition you are working towards at the tip. I think with that top picture you could run the hollow more toward the tip to get the straighter transition but I'm not sure how good it will look.

Its the "angle" of the tip that you're flat grinding... If its long and tapered it gives that more "pointed" transition. If its in a thicker more "blunt" grind then its gives the rounder look. At least that's what happens when I model this type of transition in 3D CAD. (I just basically said what Vargas Knives did but its right.)

Thanks guys, I'm definitely gonna play around w/ this more and see if I can pin-point it exactly based upon what you are telling me!

You might want to pick up a few Chinese clones to practice on, learning to regrind a new profile on high dollar folders can get mighty expensive!

Very true! I was playing around w/ a different dual grind on this $20 schrade but have to do more before I offer this one up! Gotta get a custom wheel made 1st. But I didn't really have the pointy issue w/ this one either...

 

[stezann]

Its the "angle" of the tip that you're flat grinding... If its long and tapered it gives that more "pointed" transition. If its in a thicker more "blunt" grind then its gives the rounder look. At least that's what happens when I model this type of transition in 3D CAD. (I just basically said what Vargas Knives did but its right.)

That is the correct answer IMHO