A poor angle or a poor strop?

[Sharp_Canadian]

Hey guys, hopefully all are having a good weekend.

I have a bit of a question right about now regarding a knife of mine just refusing to come back to hair popping. I've been in the knife game since childhood and the expensive obsessive game since my early 20's. This is bothering me cuz normally if something is going wrong I don't fret it and come back to it at a later point and all works out well.

The question is what am I doing wrong stropping with a convex edge on a 1095 blade. Actually it's am I doing something wrong, do I have the wrong products or is my strop just past due?

I like to think all my knifes are pretty ridiculous sharp and the knife in question is a heavy user and I do admit sometimes my heavy users are only maintained to what I believe is just further past a working edge. At any point in time they normally come back to hair popping with just a few moments on the leather though. I usually let the weight of the knife do the work for me unless it's a smaller blade, and know all about rounding out which I think may have happened?? The strop is a 3 year old flexicut with just flexicut gold compound. I normally lay to the grind then rise just that tad bit, keeping a finer edge unless it's a dedicated pounder. Is it possible my stop is worn out after years of sharpening and maintaining dozens of knifes, atleast 1 per weekend. Or is the gold compound just not cutting what I need to get this back to sharper than sharp.

Anywho I'm rambling and have never been a great writer or great at getting my thoughts onto paper. So should I be changing technique, replacing strop or replacing strop and compound to use something more aggressive then to finer?

 

[Kai Winters]

I'll offer my "less experience than I'd like", "limited materials usage", limited input to your questions starting with some questions for you.
1: What are you using for "strops"? You give us nothing to work with.
2: Finish your thought. Your last sentence ends with "th" and is incomplete.
3: Perhaps describe how your stropping your convex edge.
4: Are you stropping when you should be touching up the edge with hones/stones before stropping? Does your edge need more work than a strop can give?

My convex blades are in A2 so I can only speak to them. After watching many YouTube videos and reading many forums threads I use a very shallow angle when stropping a convex edge. I also started the process by using a Sharpie on the edge then looking at said edge after a few strokes to see where the stropping angle is wearing off the Sharpie...above, too shallow...below, too steep

I've learned how to hold the angle correctly and consistently to get a very keen edge.

I use black compound on one side and green on the other side of my strop. I use 3x12 leather.

I've also learned to not "over strop" an edge. I enjoy using the strop while watching TV and have perhaps "rolled" the edge on my elmax ZT566 by what I think is over stropping or too steep an angle. Once I achieve the desired edge I leave it alone...or try to.

 

[Sharp_Canadian]

Sorry Kai I was in the process of editing. I hit post by accident.

I tend to stay shallow while stropping. The strop being used is a flexicut with it's gold compound think it's an 2x8". I don't think the blade is past the point of being maintained on a strop as it'll still slice paper without hang ups it's just rather "teary". I do have stones from fallkniven, dmt and lanksy but always thought I shouldn't put a flat stone to a convex edge? I do also strop while listening to music or watching something on the tv, but also all on it's own paying attention to detail.

 

[Obsessed with Edges]

Decent 1095 (of quality manufacture and heat treat) usually responds pretty well to most any firm strop with some med/fine-grit compound, IF the edge coming off the stones is decent and fully-apexed. I'd think your Flexcut strop should be OK, and I've heard nothing but praise for their compound as well (haven't tried it yet).

If your strop isn't as effective anymore, I'd first make sure your edge has a clean & crisp apex coming off the stones (and on that note, what are you using for sharpening, besides the strop?). I don't see any mention of stones or any other sharpening gear in your post, so that could be a problem if you haven't used anything but the strop to maintain the edge for a while (and 3 years is a VERY LONG while, if the knife is a 'heavy user'). A strop by itself, used with anything but very coarse compound, won't be able to keep up with that much wear & tear.


David

 

[Obsessed with Edges]

Sorry Kai I was in the process of editing. I hit post by accident.

I tend to stay shallow while stropping. The strop being used is a flexicut with it's gold compound think it's an 2x8". I don't think the blade is past the point of being maintained on a strop as it'll still slice paper without hang ups it's just rather "teary". I do have stones from fallkniven, dmt and lanksy but always thought I shouldn't put a flat stone to a convex edge? I do also strop while listening to music or watching something on the tv, but also all on it's own paying attention to detail.

That answers what I'd asked in my previous post. I'd take that blade to a stone ASAP. For what it's worth, I've been using a back & forth 'scrubbing stroke' on Fine or EF diamond hones (DMT) to thin & gently convex blades in 1095 and other steels, and following with stropping on linen-over-wood with aluminum oxide compound (your Flexcut Gold should work for this).

With 1095, a finer hone is preferable if using diamond, because the abrasive will still work very aggressively on this steel; a coarser hone would be overkill. There's no reason to avoid using flat stones on convex edges, especially if those edges start getting dull. Even a quick microbevel applied with a flat hone would get your edge cutting again, most likely. It sounds like the apex on your blade is likely worn down and blunted or rounded, and it needs to be made crisp again. Might also be some rolling/denting of the edge from 'heavy use' that the strop alone is having trouble fixing (this could explain the snagging/tearing when cutting paper).


David

 

[Sharp_Canadian]

Is there a technique for stones on convex? Should I still be pulling away from the edge?

 

[Sharp_Canadian]

Thanks David. I am sort of leaning towards a blunted or rounded edge. Maybe I will try my fine dmt-diamonds. When I say heavy user it's just that...not an abuser I don't really baton or hack I carry an axe to avoid this. Do you think the pastes on a new strop will work in place of trying stones? I have always been pretty decent even as a youngster for free handing, but still worry that ill render it usless on a stone.

 

[Obsessed with Edges]

Thanks David. I am sort of leaning towards a blunted or rounded edge. Maybe I will try my fine dmt-diamonds. When I say heavy user it's just that...not an abuser I don't really baton or hack I carry an axe to avoid this. Do you think the pastes on a new strop will work in place of trying stones? I have always been pretty decent even as a youngster for free handing, but still worry that ill render it usless on a stone.

Just for fun, I'd encourage you to try your Flexcut compound on a HARD strop of wood, or paper over wood, or with denim or linen used the same way. The thin paper or fabric substrate, over the very firm backing, can make compound work more aggressively and will also minimize any risk of rounding your edge. Strop on it as you would normally do, since you've been comfortable with the technique anyway. You might get lucky and find that it does a better job cleaning up and 'crisping' your apex again. If it doesn't, I'd still HIGHLY recommend going back to your hones to get it done. Don't worry about convexing right now; just focus on SHARP. With some time and relaxed practice, you can work the convex back into it with the gear you already have, if you want to.


David

 

[Obsessed with Edges]

Is there a technique for stones on convex? Should I still be pulling away from the edge?

Didn't originally see this. As I mentioned, I've been using a back & forth scrubbing stroke, which creates sort of a 'rocking' motion in working the bevels. Assuming you're holding the blade with the edge facing toward you, this 'rocking' motion will tend to lift the spine a little bit as you push the blade away, and then lower the spine on the return stroke, coming toward you. That gentle lifting/lowering of the spine will naturally introduce some convex into the bevels. In effect, it's as if you were honing on a smooth surface with some curvature in it, such as on a flexible ruler that tends to 'dip' a little in the middle. Don't focus on deliberately lifting or lowering the spine of the blade; just keep the motion smooth and natural, and feel for FLUSH CONTACT of your bevels on the hone (this is critical, and is what will keep the apex crisp). The convex is a natural result of this back & forth freehand motion.


David

 

[Sharp_Canadian]

Hmm sounds like a good alternative. For the block of wood... Should it be prepared in anyway to make sure it's perfectly flat? I do think the flexicut strop would be much like this in a way, the leather is rather thin compared to some I see available. IMO I think it's for it's intended use is sharp tools. Quick fixes less down time. Which was sort of why it had my pondering if it had worn out. Also would choice of paper make any difference? How do you feel about the extremely fine grit sand papers on something a little more give then a solid hardwood?

 

[Sharp_Canadian]

Sorry about spelling and punctuation, being on a phone doesn't allow the ease of just looking up on the monitor for a proof read haha.

 

[Obsessed with Edges]

Hmm sounds like a good alternative. For the block of wood... Should it be prepared in anyway to make sure it's perfectly flat? I do think the flexicut strop would be much like this in a way, the leather is rather thin compared to some I see available. IMO I think it's for it's intended use is sharp tools. Quick fixes less down time. Which was sort of why it had my pondering if it had worn out. Also would choice of paper make any difference? How do you feel about the extremely fine grit sand papers on something a little more give then a solid hardwood?

The wood only needs to be free of bumps or divots, basically. Doesn't have to be dead-flat or satin-smooth. For some perspective, my 'best' strop is built with just a piece of scrap plywood from the garage, with a piece of an old linen shirt I recently retired.

For the time being, since we're trying something new here, I'd not use leather at all. As firm as good leather can be, you'd be surprised at how much firmer a thin layer of fabric (or paper) will be on wood, and the difference it'll make in the crispness of the apex; this is what I'm encouraging you to see here. I've found that a fabric-over-wood (or paper-over-wood) strop will tolerate much more pressure from the hands, without the rounding that results on leather or the heavy burring that would result if doing so on a very hard stone.

If using paper, just start out with some simple printer/copy/writing paper and try that. There are a TON of other options for this, and many will behave somewhat differently in how they hold the compound, or in how durable they'll be; but they all can work great (I spend a lot of time experimenting with this).

Using some glue or other temporary adhesive to stick the paper or fabric to the wood will work additionally to minimize any movement of it, which will also prevent the paper or fabric from lifting or curling around the apex; this minimizes edge-rounding, and it also generally makes the whole thing easier to handle, without being distracted trying to keep the paper/fabric in place as you work.

(Edit)
Forgot to answer your other question, re: sandpaper on forgiving backing. Pretty much the same view as for stropping; the harder the backing is, the less tendency there'll be for edge-rounding (which happens even faster with sandpaper). When I first started convexing edges with sandpaper, I was using a leather-on-oak strop block with the paper over the leather. For doing the basic shaping overall, that worked fine until the edge was apexed, at which time it became difficult to refine it much more. To refine the edge further, I found it much easier to flip the block over, and put the finer-grit sandpaper directly over the oak on the backside of the block. Edges always finish up much sharper this way, and it's also more effective for cleaning up stubborn burrs, using feather-light strokes on the hard-backed sandpaper (usually above 1000+ grit).


David

 

[Kai Winters]

When my convex edge needs more than what the strop can do I use wet/dry sandpaper of appropriate grits. I lay the sheet of sandpaper on a piece of drawer liner material...it is a thin piece of rubber type material...I lay this on my coffee table and place the sand paper on it close to the end of the table so when I hold the knife it is parallel to the surface across the entire edge of the knife.
I lift the spine of the knife enough to move across the convex edge with a moderate amount of pressure to create a burr. Turn blade over and repeat using finer grit paper until it is finished to the desired level of sharpness, then I strop to finish.

From the different YouTube videos I've watched showing convex sharpening they have warned about applying too much pressure when using a softer surface...mouse pad, etc...because you can round the edge rather than sharpen, so I'm careful about how much pressure I use. I thinking about picking up some balsa wood for the base of the wet/dry to see how that works.

The beauty of all this is you really can't do any damage. Perhaps your results won't be what you desired and you have to go back to the drawing board but you are learning all the time and at some point it will turn out the way you hoped. Big learning moment and from then on it is gaining experience and refining your ability.

the finished edge easily shaves arm hair.

 

[Sharp_Canadian]

Went and found a suitable piece(s) of scrap wood at my work and have paper, just waiting for the me time. I'm hoping it works as desired. If not on the way home from work tomorrow evening I will grab some 3m paper. If all fails ill hit the stones. Thanks a lot for the input guys, sometimes it doesn't hurt to ask what seems like a silly question.

 

[Kai Winters]

No such thing as a silly question...well not so sure about that but your question is a good one.
Keep us informed.

 

[Sharp_Canadian]

Hey guys sorry for the late response, but I did find some time to try some things out. The block of wood ended up working pretty good. I did end up preparing it's surface a tad bit. I couldn't get an even load of compound on the paper without sanding one side smooth. After that it did work pretty well though. Took about half an hour but I kept my strokes very shallow this time round. Seems to have taken a lot of the steel behind the edge away. I think over time it had rounded out on me. The blade travels through paper effortlessly, although just lined binder paper for now. Still won't on phone book paper so well, nor shaving again yet, but it did make a wild difference. Next step I did order a new strop, with what is said to be firmer leather and smooth side up as the flexicut has the nappy side up, hoping this will get that pow back. Will up date again soon with the new strop. Thank you guys for the quick help!

 

[Sharp_Canadian]

Also Kai. I do want to pick up some 3M sand paper for back up what grit would you suggest? Something over 1500?