Bent Blade

[2bit_collie]

So trying to hone a Greaves razor, fighting 2 issues. The minor one is that the spine thickness flares out near the toe. But the main issue is that the blade is bent (or warped) about 1/4 of the way back from the toe. So while I have set the bevel on one side completely, there is a section of the concave side where the stone has yet to touch the edge. The photo below gives an idea - you can see that neither the edge nor the spine are have any contact with the hone at the minimum point (and yes I did lap the stone before starting).

Clearly this razor was honed in the past - you can see that there is a remnant of the old bevel, which has a much more obtuse angle. As I see it my options are:
1) Just keep doing what I’m doing until I can establish the new bevel all across the edge. So far I’ve been using a 2k Shapton, but I do have coarser stones I can move to.
2) add some tape, which at least will change the amount of steel I’m having to remove. Currently the bevel angle is 17.7 deg, so not sure I want to go any fatter than that.
3) Try to hone the remaining section of the edge using the corner of a honing stone or some other solution that allows me to access the bevel. I do have a honing rod that would do this, and alternatively I could use W/D sandpaper and EdgePro honing film wrapped around a wine bottle cork. Certainly though I would have to question the quality of such an edge and the ability to maintain it.
4) Other?

 

[buca3152]

Warped is the correct word. Very common for old razors to.be warped. It's too late but a rolling stroke may have been better

 

[2bit_collie]

Warped is the correct word. Very common for old razors to.be warped. It's too late but a rolling stroke may have been better

Hi @buca3152, so I get how a rolling stroke helps on the convex side, but not understanding how to apply it on the concave side, which is where I have the issue? Unless of course the honing stone is convex enough to get into the concavity?

 

[buca3152]

If there was an edge on the blade before then you should be able to.get.one with a stone. You have to roll the blade over the stone. Part of the blade and spine on the stone but most of it is off the stone. Some guys use narrow hones to achieve this. It's impossible to tell from here though. How along are you with your honing? What I always suggest it buying 10 gold dollars cheap as you can on ebay or ali and by the time you home them all you should be ready to do other blades.

 

[2bit_collie]

Hi @buca3152,

OK this makes sense. I don’t have much in the way of narrow hones, but of course all my stones are wider than they are thick, so I could try using the edges for honing. And of course I can use W/D sandpaper on a cork, wine bottle etc. to get in there.

In terms of honing, I would say I am OK. Several years of background honing knives. I’ve been honing razors for about 6 months now and I have basically followed the eBay route you mention, > 25 razors honed to date, mostly vintage beaters. I have done rolling X-strokes on smiling blades. This is my 2nd razor with a bent blade. The other was a CVH No.24 that was probably made straight and then damaged (there was a chip in the edge that lined up with the bend line). I eventually flattened that one down, by producing even more hone wear on the one side of the toe than you can see here. So I know that can work, but looking for other options.

 

[buca3152]

If your looking for honing practice get 10 gold dollars and have at it. Im not saying that because im trying to sell you some, and my brother in law isnt in the business either. Theyre cheap as chips. A lot of the heavier grind older blades are warped. I would say maybe 30% of sheffield wedges are warped. If you want vintage I would stick to hollow ground blades. There are lots of NOS blades around. You going to pay a little more for them. But they will most likely not have issues like the warp in this razor. The one you have looks like it needs a regrind. By all means continue to hone it if you like. I would stick to flat stones though. ANd forget about sandpaper on a cork. As you run out of options for fine sandpaper at around the 2k grit. Good luck and keep on plugging. I started on razors and the last few years am doing more knives than razors. The wife beats them up daily so its a thankless job. LOL. You can even shape a gold dollar to be a smiler. And learn on that as opposed to a piece of history.

 

[Slash McCoy]

When you find yourself with a razor that has a significant lateral bend in it, one way to fix it is to clamp it in a vise between three pieces of mild steel or bronze. Two on the concave side and one on the convex side. The one on the convex side is to be located at the center of the bend, and the other two obviously are toward the heel and the toe from the bend. Tighten the vise and cross your fingers. On rare occasion you will break the razor but usually you will apply a counter bend and if you get it perfectly the razor will end up nearly straight. It usually takes several attempts to get it tuned just right. When the spine bends, the edge will follow, mostly. Don't let the bevel touch anything, of course.

Your jig pieces should be about 5/64" thick for the first few squeezes. However much it bends in the vise, it will probably spring back about 90%, and anyway you don't want the spine to touch the vise jaw, just the jig pieces. Use common mild steel, not hardened tool steel for the three jig pieces, or high silicon marine bronze if you have some.

You can tape them to your vise jaws for convenience. Or I guess to the razor but I tape them to the vise.

 

[2bit_collie]

When you find yourself with a razor that has a significant lateral bend in it, one way to fix it is to clamp it in a vise between three pieces of mild steel or bronze. Two on the concave side and one on the convex side. The one on the convex side is to be located at the center of the bend, and the other two obviously are toward the heel and the toe from the bend. Tighten the vise and cross your fingers. On rare occasion you will break the razor but usually you will apply a counter bend and if you get it perfectly the razor will end up nearly straight. It usually takes several attempts to get it tuned just right. When the spine bends, the edge will follow, mostly. Don't let the bevel touch anything, of course.

Your jig pieces should be about 5/64" thick for the first few squeezes. However much it bends in the vise, it will probably spring back about 90%, and anyway you don't want the spine to touch the vise jaw, just the jig pieces. Use common mild steel, not hardened tool steel for the three jig pieces, or high silicon marine bronze if you have some.

You can tape them to your vise jaws for convenience. Or I guess to the razor but I tape them to the vise.

OK, so the material choice is to keep the vise surface from tearing up the surface of the blade and the positioning of the 3 metal strips is to allow you to press the blade past the straight position (which you would have to do if it is going to mostly spring back to the original shape).

 

[Doc226]

I find honing wedges without tape to be a huge pain in the butt

 

[bluesman 7]

I've had good results on knives by clamping with shims and then doing a tempering cycle in the oven at 400º F. That way the bending on the shims doesn't have to be so extreme, risking breaking the piece. I clamp to just beyond straight by a small enough margin that if the blade took the complete set it would still be acceptable. You can repeat this tempering cycle as many times as you want without doing any harm as long as you don't go much above 400º

 

[2bit_collie]

I've had good results on knives by clamping with shims and then doing a tempering cycle in the oven at 400º F. That way the bending on the shims doesn't have to be so extreme, risking breaking the piece. I clamp to just beyond straight by a small enough margin that if the blade took the complete set it would still be acceptable. You can repeat this tempering cycle as many times as you want without doing any harm as long as you don't go much above 400º

Do you heat the blade at all prior to clamping, or clamp at room temperature, then heat, cool, and unclamp?

 

[Slash McCoy]

I find honing wedges without tape to be a huge pain in the butt

HAHAHAHA I find even honing wedges WITH tape to be a PITA! I really, really, do not like wedges.

 

[LJS]

You just need a good dished hone is all All that ultra flat and an old wedge just don’t jive

 

[DrStrange]

Hi @buca3152, so I get how a rolling stroke helps on the convex side, but not understanding how to apply it on the concave side, which is where I have the issue? Unless of course the honing stone is convex enough to get into the concavity?

I have a hollow ground Scargill which is very slightly bent.
I'm able to push down on the center of the edge to get it to flex down
to stone or balsa.

 

[2bit_collie]

I have a hollow ground Scargill which is very slightly bent.
I'm able to push down on the center of the edge to get it to flex down
to stone or balsa.

I can totally see that being possible with a hollow. This is a 6/8 near wedge and the spine is 0.22” wide at the bend area. Short of using a clamp as mentioned above, the spine is not going to flex.

 

[2bit_collie]

You just need a good dished hone is all All that ultra flat and an old wedge just don’t jive

This is actually the route I am planning to take as of right now. I just need to make a “dished hone” and I think I know how I will do it.

 

[LJS]

I’m not truly recommending it

And I certainly wouldn’t go dishing any hones intentionally. If you buy any old hones you will be certain to come across enough antique dished hones as it is. I will admit to successfully honing a couple of fat wedges on an awesome coti - it has a nasty dish to it that if I were to lap it the whole coticule would be gone. So I tried it a few times on wedges that clearly had second (or more) bevels from freehanding or whatever treatment. Anyway, actually worked better than most internet forums would ever agree. I think this was probably not so unusual “back in the day” given the number of dished razor hones out there.

Short of that goofing around, I just tape wedges even though I’m not a tape lover but because they often obviously need it or you simply will never reach the edge.

 

[bluesman 7]

Do you heat the blade at all prior to clamping, or clamp at room temperature, then heat, cool, and unclamp?

I clamp at room temperature. If I felt that I was stressing the piece too much I would do several cycles moving it a little each time. It's pretty easy with a piece of heavy plate steel or angle iron, C clamps and a home oven. Check the temp with an oven thermometer first!

 

[Doc226]

HAHAHAHA I find even honing wedges WITH tape to be a PITA! I really, really, do not like wedges.

True statement.


Sent from my iPhone using Tapatalk

 

[2bit_collie]

I’m not truly recommending it

And I certainly wouldn’t go dishing any hones intentionally. If you buy any old hones you will be certain to come across enough antique dished hones as it is. I will admit to successfully honing a couple of fat wedges on an awesome coti - it has a nasty dish to it that if I were to lap it the whole coticule would be gone. So I tried it a few times on wedges that clearly had second (or more) bevels from freehanding or whatever treatment. Anyway, actually worked better than most internet forums would ever agree. I think this was probably not so unusual “back in the day” given the number of dished razor hones out there.

Short of that goofing around, I just tape wedges even though I’m not a tape lover but because they often obviously need it or you simply will never reach the edge.

So here is my current thought - maybe stupid, perhaps not. I have a pretty fully-equipped EdgePro system that I got for knife sharpening. And the reality is that I have the bevel 90% set. I have one side of the bevel at 100%, the other side just has the 1/4” section where the bevel doesn’t touch the stone. I plan to take a scrap of 1/8” Acrylic that I use for making scales and sand it on one side to create a mildly convex surface. Then I will glue that to an EdgePro sharpening blank. I can then put the razor on the EdgePro, use a sharpie to dial in the angle of the existing bevel in that one spot, and then work the edge with a progression of W/D and film attached to the convex surface of the modified blank. I have W/D up to 8k and also have EdgePro films 3000 and 6000, which are rated as being equivalent to 10k and 18k grit stones. So the thought is that as I go through my normal progression I can keep moving back and forth between the normal stones for 90% of the edge and the EdgePro for that one area where I have a slightly fatter bevel angle. 0.9u off the 6000 film won’t be as nice as 0.1u on pasted balsa, but its only a fraction of the edge and it certainly shouldn’t be that rough.