How do you do this grind?

[Drac]

Hi guys,

I posted this thread over in Steve's forum but I know a lot of people don't read all the forums so I'd thought I'd try here as well. I'm looking to see if anyone knows how this curved grind is done. I read about it in a Blade or KI article months back but they didn't say how the grind was done.

Here's an example on an Arpad Bojtos' knife:



I like the curved grind lines and want to try them on a knife of my own but don't even know where to start on it. Just as a clarification, I'm curious of how the curved grind is done. Most of mine are 90 degrees not the gentle curve of this.

Thanks,
Jim

[AUBE]

i know of two ways,

you can use a stiff belt and run the sander with the belt hanging off the edge of the platten..and then take your time when grinding. the more belt that hangs off the side of the platten the longer the curve.

or you can use a drum (or the contact wheel) with the knife pointing up and down and grind like that. grinding so the grinding marks run paralell with the blade instead of perpendicular.

both ways take practice and im not very good at either method. i had better luck grinding the second way. i really envy the makers that can do this consistently...especially on double edged knives

[Ray Rogers]

You are probably already aware that the border of the curve in question was not created on a belt sander, it was carved into the front of the full thickness ricasso.

Now, even if he did a standard 90 degree grind at a point about 3/4 of an inch in front of the botom of the carved curve (at the edge of the blade) that would leave plenty of steel for him to carve that nice rounded part into the main bevel.

In other words, my guess is it may have been started on a belt sander but the majority of that curve was done more or less by hand (with maybe a Dremel type tool to assisst)....

[Drac]

Thanks both,

Aube, I can wrap my mind around those images. Your right about it being difficult. I'd have to learn a whole new set of "feels" on when to push, when to twist, ect. As for me doing it consistently I guess it falls back to the same old first lesson:

Practice
Practice
Practice

Ray, I guessed it was carved it but with how little experience I have in the field I try not to make to many assumptions. Most of those seem to back fire for some reason . The maker’s bios says he doesn't use power tools on his knives. A man of infinite patience.

Thanks again,
Jim

[J.Arthur Loose]

Various jewelry/machining cutting / carving bits, grinding / polishing wheels. Lots of hand finishing to smooth transitions.

A Dremel would blow out in about two seconds. You'd need a good 1/3 HP or better flexible shaft such as those you get from Rio or other jewelry suppliers.

[Andrew Garrett]

I'm gonna give this a try on a scrap bar tonight. I'll post pics if I am successful. I'll pretend I never read this thread if I fail.

I think I know how, but I want to try it before I open my mouth.

[Don Cowles]

See David Broadwell's DVD on carving steel from Center Cross.

[TikTock]

I think he just ground it that way. You've never rounded a plunge by rotating the blade at the plunge? I think he started with aproximately a 60 degree plunge towards the tip, then feathered the top back with a wrist roll on each pass, never grinding back to that inital bottom plunge at the edge

[fitzo]

Bojtos uses no power tools. That was all chiseled and filed. Pretty much an artisan, I'd say, Old World style.

When ground, that type of "plunge" is closest approached by drifting the belt off the platen/wheel and angle the blade is held. there've been a couple dsic-grinder wizards over the years that managed to pull it off superbly, too.

[ranger1]

That is simpy hard work and patiance.More than I have but I am working on that,work like that is at a level that a rooki like me strives to reach.

[J.Arthur Loose]

Nice, Fitzo... didn't know it was handwork.

I sat in on a steel carving workshop with Daniel Stephan and Donal Bell at the First and Only Annual New England ABS Hammer-In of 2002. They did a good job with the tools previously described. You could certainly do it with chisels, files & paper if you had the time!

[Gene Chapman]

Ball end mill with a CNC machine tool??

[Drac]

Wow,

Everyone showed up after I went home last night! Thanks guys.

I have the carving video, got it the first week it came out

Jim