VIDEO: Why polish and reprofile? -- answered

Nice video.

Since you've already got some consistent results with those edges, what about putting some microbevels on them to see how much that improves things?
 
KennyB said:
Nice video.

Since you've already got some consistent results with those edges, what about putting some microbevels on them to see how much that improves things?
Click to expand...

Wouldn't the microbevels just be the same as the higher edges tested i.e. the 20* Endura with a 30* microbevel would cut the same as the 30* knife right? Or the 30* Endura with a 40* microbevel would cut at the pressure as a straight 40* edge. The microbevel is applied to give the blade's edge strength and ability to take more sharpenings without removing more stock. Yes/No?
 
cziv said:
Wouldn't the microbevels just be the same as the higher edges tested i.e. the 20* Endura with a 30* microbevel would cut the same as the 30* knife right? Or the 30* Endura with a 40* microbevel would cut at the pressure as a straight 40* edge. The microbevel is applied to give the blade's edge strength and ability to take more sharpenings without removing more stock. Yes/No?
Click to expand...

Yeah, there's that practical use for them, but I've also heard a lot of theory that they provide relief in much the same way that a convex edge would and thus improve performance. So I think it would be interesting to see these V bevels with already pretty consistent results have a V bevel put on, and see if there's any dramatic improvement. You know, cut through all the theory, and use this test which so far seems pretty objective to me provided the data that unit has been tossing around.
 
Congrats unit on a great video and post, well done. The test itself was well thought out w/ controls and media that anyone could duplicate, and your presentation was clear and concise. (Do you have a background perhaps in sciences?)

I can't wait to see what other tests you have in the works. Edge retention? Blade steels? I will keep an eye out!
 
MassMatt said:
Congrats unit on a great video and post, well done. The test itself was well thought out w/ controls and media that anyone could duplicate, and your presentation was clear and concise. (Do you have a background perhaps in sciences?)

I can't wait to see what other tests you have in the works. Edge retention? Blade steels? I will keep an eye out!
Click to expand...

Thanks a lot for the kind words!

I do have a fair background in science, but I am really trying to keep this stuff simple. I also work in my spare time teaching/tutoring kids so I am always looking to improve my communications skills.

I have just finished another demonstration video that I hope to post tomorrow evening (when I have access to the bandwidth). I fear it may be a bit dry, but we will see how well it is received.
 
KennyB said:
Nice video.

Since you've already got some consistent results with those edges, what about putting some microbevels on them to see how much that improves things?
Click to expand...

Thanks for the suggestion. I may try that...

The next round will explore how these edges hold up to some cutting. The "stock" edge in the test has secondary bevels (but the primary bevels are not polished). In my next video the secondary bevel received a bit of polishing (had to restore the damage done in the first video when the blade hit the base). Not exactly what you were hoping for perhaps, but perhaps you will find it interesting?
 
unit said:
Thanks for the suggestion. I may try that...

The next round will explore how these edges hold up to some cutting. The "stock" edge in the test has secondary bevels (but the primary bevels are not polished). In my next video the secondary bevel received a bit of polishing (had to restore the damage done in the first video when the blade hit the base). Not exactly what you were hoping for perhaps, but perhaps you will find it interesting?
Click to expand...

Please put a swatch of carpet in the base of your jig unit. It was painful to hear the edge hit metal.

Yeah, there's that practical use for them, but I've also heard a lot of theory that they provide relief in much the same way that a convex edge would and thus improve performance. So I think it would be interesting to see these V bevels with already pretty consistent results have a V bevel put on, and see if there's any dramatic improvement. You know, cut through all the theory, and use this test which so far seems pretty objective to me provided the data that unit has been tossing around.
Click to expand...

I get what you're talking about KennyB, it makes sense. :thumbup:
 
The problem with microbevels would lye in the materal being cut. The rope/string is already binding on the side of the knife and a micrbevel increasing the thickness of the cutting edge would only make it worse. Micrbevels are great for edge retention but lack the pure cutting ability a straight V has.
 
unit said:
The next round will explore how these edges hold up to some cutting. The "stock" edge in the test has secondary bevels (but the primary bevels are not polished). In my next video the secondary bevel received a bit of polishing (had to restore the damage done in the first video when the blade hit the base). Not exactly what you were hoping for perhaps, but perhaps you will find it interesting?
Click to expand...
I was hoping you'd do an edge retention test as a follow-up. Looking forward to it!
 
Very well made video, I may be nitpicking but I thought the force to cut the string remains the same, what changes is the space the force is applied in, meaning that a change in edge thickness will mean a greater change in force applied to the blade through the handle.

A change of .6 pounds is significant, of course media density and composition plays a role as well, I think a better display would include another media that is more dense, that would show a larger difference (on the scale)

Oh, and for how tight the rope is held, a wider rig could accommodate something like a fish scale, or keep the same rig and suspend a weight from one side.

For those that want to see edge retention tests, the data obtainable without a system designed purely for that purpose(CATRA) would be anecdotal at best.
 
Skimo said:
Very well made video, I may be nitpicking but I thought the force to cut the string remains the same, what changes is the space the force is applied in, meaning that a change in edge thickness will mean a greater change in force applied to the blade through the handle.

A change of .6 pounds is significant, of course media density and composition plays a role as well, I think a better display would include another media that is more dense, that would show a larger difference (on the scale)

Oh, and for how tight the rope is held, a wider rig could accommodate something like a fish scale, or keep the same rig and suspend a weight from one side.

For those that want to see edge retention tests, the data obtainable without a system designed purely for that purpose(CATRA) would be anecdotal at best.
Click to expand...

Thanks for the insight. I think what you may be getting at is the idea PRESSURE (force/area). You can generate more separating pressure by either increasing the force at the handle or the area of the blade contacting the media (with a thinner angle).

I would like to make a more elaborate rig with constant tension on the string (and perhaps bigger diameter string/rope) in the future perhaps. For now it is a demonstration that is loosely bounded and not nearly as scientific as some would like. I think it is fun and interesting, so I am doing it.

I agree that anything I do regarding edge retention is anecdotal, and certainly not as constrained as CATRA. I have no intentions of competing with real lab studies...but I am working on something that demonstrates something about the edge retention of these knives (and I thought it was a lot more fun than watching a robot cut stacks of cards LOL)

I really appreciate your thoughts and interest.
 
knifenut1013 said:
The problem with microbevels would lye in the materal being cut. The rope/string is already binding on the side of the knife and a micrbevel increasing the thickness of the cutting edge would only make it worse. Micrbevels are great for edge retention but lack the pure cutting ability a straight V has.
Click to expand...

That was my suspicion also.

It would not take much time to actually put on a micro bevel and cut some string, but I suspect that my gear is not sophisticated enough to detect the small difference introduced by a micro bevel. That is just a hunch though.
 
You must log in or register to reply here.
Back
Top