Cardboard Wheel Sharpening

[SvenDreyriAx]

I know he's probably very experienced, but surely it would be safer to sharpen it so the sparks go away from him :P

[jonwelder]

Where is he doing this at? Is this how they sharpen "shanks" at night in prison?

[jtcustomknives]

He is a custom knife maker as am i and when it comes to getting a sharp edge on a knife he is the man. i have had long talks on the phone with him about getting the sharpest edge possible and he says use the paper wheels all the way. I must say he is very respected in the knife making world for the sharpness he can achieve. as to the idea that because its sparking its loosing its hardness is crazy, as long as the person knows what there doing.

[jtcustomknives]

your not going to see a drop in hardness till you hit 375-400 deg. and even then your going to have to hit 450-500 deg to see a drop as knives are tempered after heat treating at a temp between 375-450. doing light grinding is not going to heat the edge much at all. i regrind blades and use 50 grit grinding belts that is running at around 3600 feet per sec. and yes it gets warm but i dip in water after every pass. here is his website address, and if your need something sharpened send it to him.

[halomaniac94]

Paper wheels grind off sparks Since when is paper that hard :P

[wolpack1116]

The paper wheels have grit, 220 or so, glued to them. The kits have enough to replenish the wheels several times.

[noss4]

They are very safe to use and he has 17 years experience using them.

[noss4]

I have a knife from the producer of this video it's very sharp and stays sharp. I'm going to get a set of these wheels.

[azngangstr0]

Sparks from sharpening w/ a carboard wheel?! Interesting...

[pooface510]

Not if he doest lent it get hot enough.

[MisterBaz1]

Sparks = heat.

The whole knife doesn't need to get hot. Even in that tiny area of the edge it can get hot enough to ruin the edge retention. That doesn't mean it won't get sharp. That just means the edge will wear out faster.

[brreed82]

Sparks=heat. yes

but what your saying is that every production knife and most customs are junk. You cant grind every knife by hand or w/ water wheels. There would be no knives to buy. Tolerances, ground blades are FINE

[n7cav]

If sparks are leaving the edge, you're de-tempering the steel...

[Roger1379]

You won't ruin the heat treatment unless you get past like 220degrees celcius, the sparks are metal.

[MisterBaz1]

Why do you think the metal is sparking? It IS getting hot enough.

[Roger1379]

No, it is metal being ground off the blade, cardboard has small abrasive clay particles, the abrasive grinds off metal, he may put something like Chromium Oxide which is a finer abrasive which does remove metal, if it is overheating, then he would not be able to hold it, have you ever even tried to grind a blade by power tools?

[MisterBaz1]

No matter the abrasive, that fast spinning wheel can heat up that tiny surface enough to cause a shallow de-tempering. There is enough energy being put onto the edge by that wheel that it is causing those small metal particles to spark. The whole knife doesn't have to get that hot, only that shallow spot on the metal for a brief period where the wheel touches the steel.

I make knives as well. I use power tools on blades all the time, but never to sharpen them. I use Japanese water stones.

[Roger1379]

But have you used card board wheels?

[MisterBaz1]

I've used all kinds of things. The best option I've come across is stones. It takes some skill, but you get a better product afterward.

If it is just a camp/utility knife, you'll be sharpening it routinely anyway. Cardboard wheel shouldn't be a problem. On nice kitchen cutlery, you can be sure your best option is stones. Edge development and retention is much better. That, coupled with the fact you cannot sharpen Japanese single-bevel knives with a wheel.