Touching up Buck's 440C

[Obsessed with Edges]

David (Owe),

Based on earlier comments and some reading in a whittling book, I've been attempting to use wet/dry to strop and sharpen with no good success. It appears to me that this is blurring the line between sharpening and stropping. I've tried 600, 800, and 2000 backed on wood and on leather. Ive tried edge leading, trailing and circular to no avail. Can't shave forearm hair.

Mind sharing your wisdom? Your tips on smoothing the shoulders and sharpening basics have been a massive help!

Don't give up on it yet. I've come to viewing the 'blurring the line between sharpening and stropping' as a good thing, in this case.

With my 112, that was a learning project for me. It took a while, because the original factory edge on it (be it 'convex', as mentioned, or something else vaguely akin to convex) was very obtuse, with an even thicker 'V' secondary at the edge. My goal was to thin it significantly, so a lot of metal had to be removed. I think I started at around 220 grit, then went through a full sequence up through 2000, eventually. At the time, I think I polished it with Simichrome on a strop. Since then, I've touched it up using diamond compound and/or high-grit sandpaper, as I mentioned earlier.

The older 110/112 edges on the 440C blades were very thick near the edge. So, the biggest goal, as I see it, is to thin that down first. Once that's done, the remaining stages become a lot easier. I'd also recommend that you give some thought to going a bit thinner than 20°/side at the edge. I think this steel, on these Buck blades, is plenty durable enough to work well down to 15°/side. And the 'shaving sharpness' is much more easily attained at that angle.

I've often 'cheated' a little bit at convexing, by using my guided systems (Lansky or DMT Aligner) to re-bevel the edge first to a fairly acute angle (~15°/side). Then use the sandpaper stropping to smooth out and convex the shoulders a bit. It works very well, and to me, is a bit easier than going through the full convexing sequence with the sandpaper.

 

[knarfeng]

For whatever it means from me for you folks that aren't long time Buck specialists,

Steel and sharpening discussion on Bucks is led by Headmasters Knarfeng and D. Martin. Ask them and you get the straight information. My 300 series folders were never privledged to receive 440C blades, made do with 440a till a few got 425M and then finally 420HC. I use crocks,Lansky diamonds, Si paper and leather and white paste, depending on my mood. 300Bucks

When Buck was using 440C, Schrade and Camillus were making the 300 series. So the blade alloys on the 300 series were the alloys those companies used. But, you knew that.

A good friend of mine got rid of his 110 back in the day and replaced it with a look alike from Schrade in Schrade+. The 110 was 440C and he couldn't sharpen it easily with his Washita stone. The Schrade + was 440A, and he COULD sharpen that with his standard stone.

 

[pinnah]

David (OWE), when youre stropping/sharpening 440C on wet/dry, do you use wood or leather as a backing?

Do you use edge trailing or edge leading strokes?

Do you work the edge to a burr prior to movin up in grit?

Thanks!

 

[Obsessed with Edges]

When Buck was using 440C, Schrade and Camillus were making the 300 series. So the blade alloys on the 300 series were the alloys those companies used. But, you knew that.

A good friend of mine got rid of his 110 back in the day and replaced it with a look alike from Schrade in Schrade+. The 110 was 440C and he couldn't sharpen it easily with his Washita stone. The Schrade + was 440A, and he COULD sharpen that with his standard stone.

I'd never fully thought of that sharpening comparison in these terms until now, but that's a very good lesson in the role (at least in part) of carbon in the alloy, specifically. :thumbup:

440A and 440C would be otherwise identical in makeup, except that 440C has a much higher carbon content (440A = 0.65 - 0.75%, 440C = 0.95 - 1.20%). There's a certain 'threshold' of carbon content, past which the 'extra' carbon combines with the abundant chromium in the alloy (16-18%, in both steels) to make those harder chromium carbides. Much more of those in 440C, than in 440A.

 

[Obsessed with Edges]

David (OWE), when youre stropping/sharpening 440C on wet/dry, do you use wood or leather as a backing?

Do you use edge trailing or edge leading strokes?

Do you work the edge to a burr prior to movin up in grit?

Thanks!

I used leather on oak, edge-trailing strokes (as in stropping), and I always work to a burr before moving on in grit. Incidentally, the strop block seen in the pics I posted earlier, with my 112, was the same one used with the sandpaper for that project. That strop block was obviously using green compound, but I've since settled into using diamond compound for stropping that blade.

 

[pinnah]

Plus, the first stone Buck sold and recommended for use to sharpen their 440C blades on was a SiC stone made by the Carborundum Co.. Here is a photo of the stone and box with an early model having a blade of 440C. Yes, agreed a SiC stone works well when sharpening this steel.

DM, sounds like you good success stropping Bucks 440C back to shaving sharp.

Could you more about your approach?

Edge trailing? On wood or leather? Stropping compound?

Thnks!

 

[David Martin]

I do mine about like Obsessed, only I don't take it to as fine a grit. Agreed, one first must remove that convexed shoulder at the edge or thin it down. That edge style was the thinking at that time. Should you pick-up a 3 dot 110 or 112 you'll quickly notice the blade style was changed and no more convex edge. Instead, now it has a full hollow ground, a much better cutter and still a 440C blade. Perhaps, look for one of those to start with. Taking my time I reduce the convexed edge on a Norton combination 100 grit SiC stone and work up a burr, using edge leading strokes. Then flip the stone over and work the burr down on the fine side which will not fully remove it. Then I take it to a leather strop or my board stop ( as a hard backing strop does not convex the edge) using edge trailing strokes, both have 300 grit SiC slurry applied and using as few strokes a possible, remove the burr and use it at that level. Should I dull it I merely return it to the board and strop it back to sharp. This saves your blade steel. Your welcome, DM

 

[pinnah]

Then I take it to a leather strop or my board stop ( as a hard backing strop does not convex the edge) using edge trailing strokes, both have 300 grit SiC slurry applied and using as few strokes a possible, remove the burr and use it at that level. Should I dull it I merely return it to the board and strop it back to sharp. This saves your blade steel. Your welcome, DM

DM, this is super helpful. Couple of clarifying questions....

1) Can you suggest a source for SiC compound? I've been googling for SiC and lapping compounds and haven't found a source or brand. SiC is harder than the carbon oxide found in most stropping pastes, correct?

2) 300 grit strikes me as quite aggressive. When you are touching up 440C on a strop with this material, this will remove material, correct? This is more than just straightening a curled edge as one does with carbon steel on a less aggressive strop/steel, yes?

3) When you touch up a 440C blade in this manner, do you "strop" to the point of creating a (small) burr, or do you alternate sides with each stroke?

Thanks again,

Dave

 

[David Martin]

This is really not that complicated... You merely gather it off the fine side stone after sharpening your blade as some is loosened from sharpening it. Should you need more use a wire brush or file and catch it on paper placed underneath. I can tell you need some experience... Its not 'quite agressive' and it does not remove material. At this point (prior to taking it to the strop) the edge should not even be curled... You should not even feel a curl when you take it to a strop, that should have been removed at the prior stone??? NO, your not creating a burr on a strop--- your removing it. It should be much refined at this point, NOT FELT, hard to see requiring magnification. I see why your having trouble sharping. Get John Juranitch's book on The Razor Edge Book on Sharpening. Its a good book that will help you get the basics of sharpening. Also, read some of the other applicable posts in this forum, that will help you as well. DM

 

[pinnah]

This is really not that complicated... You merely gather it off the fine side stone after sharpening your blade as some is loosened from sharpening it. Should you need more use a wire brush or file and catch it on paper placed underneath.

Thanks. That's a useful tip. Presumes the use of a carborundum stone though, yes? In lieu of that, can you suggest an uncomplicated source as I've not been finding SiC compound using Google (other than industrial sellers).

I can tell you need some experience...

That's a very astute observation. In fact, that's why I asked the question. I appreciate the help.

At this point (prior to taking it to the strop) the edge should not even be curled... You should not even feel a curl when you take it to a strop, that should have been removed at the prior stone??? NO, your not creating a burr on a strop--- your removing it. It should be much refined at this point, NOT FELT, hard to see requiring magnification. I see why your having trouble sharping.

Ah... My confusion lays with this. In your previous post you said...

I do mine about like Obsessed, only I don't take it to as fine a grit.

And prior to that, OWE said, with respect to using wet/dry on a leather strop board...

I used leather on oak, edge-trailing strokes (as in stropping), and I always work to a burr before moving on in grit.

I believe my confusion here is that OWE is talking about a sharpening method (meaning, taking the edge to a burr) and you are talking about stropping only (meaning, removing the remnants of a burr). I think this is more clear now.

Get John Juranitch's book on The Razor Edge Book on Sharpening. Its a good book that will help you get the basics of sharpening. Also, read some of the other applicable posts in this forum, that will help you as well. DM

I'll look for it. Thanks again for the help.