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crimedog72
01-08-2013, 02:12 PM
I'm pretty new to sharpening (have been working at it for a couple months) and have been getting reasonably good results with my current setup of 3 water stones that I bought for sharpening woodworking tools several years ago, but never really used for that (2 labeled 'Splex Japanese water sharpening stone', 800 and 1200 grit, and one labeled 'Suehiro Ohka water finishing stone', 6000 grit). I have been working mostly on my older knives, a mix of Sabatier and Dexter carbon and Forschner and Henckels stainless, most of which have seen a lot of use since last being sharpened.

So, the end results have been decent, but it feels like it is taking me a looooong time to get there, sometimes 45 minutes or more per side on my coarsest stone to raise a burr. I use sharpie to check progress and it looks like I'm hitting the bevel pretty consistently. Once I raise a burr on each side using the coarsest stone, progression thru the remaining stones goes a lot faster.

So I guess my question is, can I speed up this process, and if so, how? Is this just a matter of putting in more time on the stones? Would upgrading one or more of my stones likely help (getting a coarser stone, maybe, or replacing with something that cuts faster)? recommendations?

SpikeC
01-08-2013, 02:29 PM
You could increase the angle that you grind at. If your knives have an edge angle of around 20 degrees a side, as those probably came with, and you are grinding at 15 or so, it would take a long time to get to the burr.
Once you have gotten to that stage you should not have to go through that again for quite a while. It sounds like you were thinning them behind the edge!

bieniek
01-08-2013, 02:30 PM
800 is not really the most useful grit to repair edges or the places on a blade where there should be an edge.

So If it is the first time you did sharpening in 20 years, then yeah, it can take 45 minutes.

If it is restoring an edge lost a month ago however, then theres a problem. I would say wobble.

crimedog72
01-08-2013, 02:38 PM
You could increase the angle that you grind at. If your knives have an edge angle of around 20 degrees a side, as those probably came with, and you are grinding at 15 or so, it would take a long time to get to the burr.
Once you have gotten to that stage you should not have to go through that again for quite a while. It sounds like you were thinning them behind the edge!


ah...thinning behind the edge was going to be my next question. I don't think I'm doing that yet, as I've been trying to stick with the original bevel and verifying using sharpie. have stayed pretty consistent as far as removing the sharpie marks where I think I should, and not in other places.

crimedog72
01-08-2013, 02:42 PM
800 is not really the most useful grit to repair edges or the places on a blade where there should be an edge.

So If it is the first time you did sharpening in 20 years, then yeah, it can take 45 minutes.

If it is restoring an edge lost a month ago however, then theres a problem. I would say wobble.

20 years would be a stretch...but these are definitely not month-old edges I'm working on. I suspect the beginning edge condition is a contributing factor here.

If that's the case, would a coarser stone be likely to cut this time down by much?

Benuser
01-08-2013, 05:43 PM
If the steel has been steeled a lot, it has been fatigued, and should be removed. I guess your blades are thick behind the edge, have fatigued steel, AND you're not always reaching the very edge. I would start to build a relief bevel at 10 degree per side until you've a burr. So you're sure the old steel has been removed.
Sandpaper is a cheap and effective way to do this - grits P120-240-320.
From this point you may start to set your bevels at some 15 degree per side. Use the P320 to start with.
Don't overpolish your soft stainless, it's counterproductive. Stop after a few edge trailing (stropping) strokes on your J1200.

SpikeC
01-08-2013, 05:55 PM
I think 15 degrees is a bit much for these blades.....

Benuser
01-08-2013, 06:40 PM
I think 15 degrees is a bit much for these blades.....
I guess you mean 15 degree per side it's too acute. As always, it depends.
For the carbon Sabatier, just give it a try. Some hold it, others don't.
For the others, it's probably a little too acute.
It's very easy to correct in function of steel and use. And the result after an increased angle will be a strong convex edge.

bieniek
01-10-2013, 06:07 AM
20 years would be a stretch...but these are definitely not month-old edges I'm working on. I suspect the beginning edge condition is a contributing factor here.

If that's the case, would a coarser stone be likely to cut this time down by much?

Diamond plate would eat metal from that kind of "softee" in no-time.
Straight after you could use 800 grit.

crimedog72
01-10-2013, 09:57 AM
Diamond plate would eat metal from that kind of "softee" in no-time.
Straight after you could use 800 grit.

I will give this a shot.

joetbn
01-10-2013, 02:45 PM
Diamond plate would eat metal from that kind of "softee" in no-time.
Straight after you could use 800 grit.

+1 on plate, an Atoma 140 or DMT XC, it can (should) also be used to flatten your other stones. Also maybe consider a Beston 500, cuts really fast and you could probably skip your 800 and jump right to 1200 after setting the bevel with the Beston.

crimedog72
01-11-2013, 02:27 PM
I have only used my plate (atoma 140) to flatten stones so far. For blades, should it be used dry or with water?

crimedog72
01-11-2013, 02:29 PM
btw, thanks to everyone for the advice. Really appreciate the info.

Zwiefel
01-11-2013, 02:33 PM
Looks like you are following the same path as me a few months ago! Congratulations on your new acquisitions, both equipment and skills.

I've been doing a lot of sharpening of friends/neighbors knives just to get the time in on the stones. Of course, that means nearly everything I'm working on is both extremely beatup and low-end, stamped blades. But it's still good experience for locking in the muscle memory for how to hold the blades and the motions across the stones.

Oddly, I've found these crappy knives to be about 2-5X as much work to sharpen as a decent knife. Some of that is the extent of the damage, but I think some of it is the nature of the tough/soft steels in most of these blades.

Yamabushi
01-12-2013, 03:49 AM
I have only used my plate (atoma 140) to flatten stones so far. For blades, should it be used dry or with water?

Whether flattening stones or working on knives always wet!

vicv
01-13-2013, 04:17 PM
QUOTE=Zwiefel;171325]Looks like you are following the same path as me a few months ago! Congratulations on your new acquisitions, both equipment and skills.

I've been doing a lot of sharpening of friends/neighbors knives just to get the time in on the stones. Of course, that means nearly everything I'm working on is both extremely beatup and low-end, stamped blades. But it's still good experience for locking in the muscle memory for how to hold the blades and the motions across the stones.

Oddly, I've found these crappy knives to be about 2-5X as much work to sharpen as a decent knife. Some of that is the extent of the damage, but I think some of it is the nature of the tough/soft steels in most of these blades.[/QUOTE]

I agree. It seems the cheap stamped knives are awful to sharpen and all that work goes to nothing as they dull quicken than they sharpen. Especially the really shiny ones. My mother has a stamped wusthof nakiri which won't sharpen freehand. Has to go to the belt grinder as even a 220 naniwa won't scratch it. For the op what I do is as others have mentioned. Cut a relief bevel with a course stone then raise the spine a hair on your 1200 and a couple strokes and you'll have a sharp and strong edge(must still experiment with angles for that knife). Then subsequent sharpenings will be done quickly till the relief needs to be ground again

tk59
01-13-2013, 08:19 PM
It should only take a long time the first time around. You've just rounded your edges after a while. After you establish your new bevels, don't wait so long in between sharpenings and the burr will form pretty much immediately. If I were you, I'd just put in the time. Once you know how to sharpen, nothing improves your edges like a little muscle memory.