Lansky consistent bevel difficulties.

K

Kai Winters

Joined
Mar 16, 2012
Messages
939
Hi all,
I am using the Lansky system, and have been for several months. I use the medium and fine diamond hones, Arkansas hard, ultra-fine and sapphire ceramic hones for the final polish.
My problem is keeping the bevel consistent when going from the ultra-fine to sapphire hones. I can see a different bevel, though slight, between the hones.
I use the same amount of strokes, make sure the "wire guides" are flat and level and keep the same pressure on the hones but can't get them the same.

This is only apparent when I look at the edge with my microscope at work. Using my 16x jewelers loupe I can't see anything but a nice shiny edge.
Yes I am being obsessive but what the hell, it's not a bad obsession.

Has anyone else experienced this and what have you done?
Thanks
 
I think all of the instances I've seen (myself) with this issue, it's been due to the blade pivoting up/down in the clamp, or even slipping back into the clamp. This can happen for two reasons, as I see it. The first is due to the clamp not being fully flush to the sides of the blade, allowing it to 'wobble' a tiny bit up/down or slip. The second is if the blade isn't deeply set into the clamp, with only a small part of the spine being held. Only takes a tiny bit of excess pressure to make it deflect up or down. Using too much pressure, in either case, will make the problem worse. Too much pressure can also flex the rods too much, creating inconsistency in the angle.

I think the most important part of using a clamped system is getting the blade properly set up in the clamp in the first place. Make absolutely sure the blade can't move at all (up & down, or slipping), before starting with the first hone. And once started, be sure to keep pressure as light as possible throughout the sequence. That really minimizes any chance of the blade wobbling up & down, after first making sure it's clamped tight & flush. Keep a very close eye on the bevel, when transitioning between each hone. Maybe re-mark the bevel at each stage with a Sharpie, to be sure the angle is staying consistent. If it isn't, stop immediately and figure out what's changed in the setup.
 
Thanks for the input, it makes a lot of sense.
Yes the blade does move a bit. I am/was using a bit of bicycle inner tube so an not to mar the finish. I think I'll try using some masking tape instead.
 
All clamping systems where the knife is fixed in its position in the sharpening tool - and the sharpening angle is locked, is very exact because the law of physics rules = the edge WILL be flat, it cannot be anything else.

If the knifes moves – you will see a different angle on the edge. If your sharpeners is different worn out (different height on the sharpeners) – you will also see a different angle on the edge when you change sharpeners.

In my mind, this is a good thing – because you must also think what is it you really see here? When the blade is fixed, and the sharpening angle is fixed, you can see very, very small variations on the edge. It is possible to se variations down to 1/100 parts of 1 degree with your naked eye when you have good light on the edge.

• Those small variations of the edge angle tells you that your edge is really flat, 100% flat. That is a good edge quality check!

• When you sharpen by freehand, the edge will not be 100% flat – and - you cannot see any variations on the edge.

If you use “soft” sharpeners – all sharpeners must have exactly the same height – and you will not see any changes of the sharpening angle.

If your sharpeners have different height – you must be able to adjust the sharpening angle to compensate the differences in height = free sharpening angle is a good thing to have on a sharpening tool.

Thomas
 
I tried a couple of materials to avoid possible marks on the blade spine in the GATCO clamp. I tried the masking tape. None really allowed the clamp to grip the blade. They did cushion the clamp but the movement and lack of grip on the blade concerned me.

All of my blades are users and are scratched from use and carry anyway so I just decided to clamp and sharpen and not worry about any possible marking. I have been happy with the even bevels and non-worry about movement and slipping.

One problem with trying to cushion the clamp is that it reduces the clearance between the hone and the clamp on the lowest angle setting. The GATCO can reach a bit smaller of an angle than the Lansky so perhaps it will not be a problem for you. I do my kitchen cutlery using the 11° per side slots. Additional clamp thickness can cause problems especially for narrow blades like paring, boning, or fillet knives.

If you find something that works keep us angle guided guys posted.

Good Luck.
 
Kai Winters said:
Thanks for the input, it makes a lot of sense.
Yes the blade does move a bit. I am/was using a bit of bicycle inner tube so an not to mar the finish. I think I'll try using some masking tape instead.
Click to expand...

The best solution I've used, for preventing the blade from slipping in the clamp, is a piece of medium/fine grit wet/dry sandpaper folded over the spine of the blade, with the grit surface against the clamp (for obvious reasons), and the paper backing against the blade. The paper backing does a great job gripping the blade, even when it's wet. Before using it, make sure all surfaces are clean, to minimize any chances of trapping abrasive particles between the blade and the backing of the sandpaper, to prevent scratches.

I've tried masking & painters' tape, but it sometimes loses it's hold on the blade, so it slips. Especially when wet.
 
Try a thin layer of contact glue in the clamp. Let it dry – and you have a “rubber” protection against scratches – and the knife will be clamped better. The layer shall be thin and evenly flat!

Thomas
 
Thanks for the advice and suggestions !
The knife I am having this problem with is my BM 585 mini-barrage.
I read your replies carefully and put your advice to the test last night. Voila...perfect single bevel and hair popping sharp, with a great polish. I put the blade in the clamp without any covering. It held just fine, no movement at all and no marring either...bonus. I think the biggest thing I did right was to ease off on how much pressure I put on the hones. I used very little pressure...barely more than the weight of the hone itself and started with the fine diamond hone then the black Arkansas followed by the ultra-fine and blue sapphire ceramic hones for the final polish.

Just a nice even bevel with a great polish across the edge. It is the nicest job I've done. Thanks a lot !
 
Kai Winters said:
Thanks for the advice and suggestions !
The knife I am having this problem with is my BM 585 mini-barrage.
I read your replies carefully and put your advice to the test last night. Voila...perfect single bevel and hair popping sharp, with a great polish. I put the blade in the clamp without any covering. It held just fine, no movement at all and no marring either...bonus. I think the biggest thing I did right was to ease off on how much pressure I put on the hones. I used very little pressure...barely more than the weight of the hone itself and started with the fine diamond hone then the black Arkansas followed by the ultra-fine and blue sapphire ceramic hones for the final polish.

Just a nice even bevel with a great polish across the edge. It is the nicest job I've done. Thanks a lot !
Click to expand...

That's great to hear, Kai. :thumbup:

I agree, light pressure solves so many issues. The other plus to going lightly, for me anyways, is it makes it easier to feel the feedback from the hone. I place the pad of my index finger atop the hone and directly above the area being sharpened, and pay close attention to the feel of the hone on the blade, via that finger pad. It can reveal a lot, if you pay attention. When transitioning from one grit to the next, you can usually feel when the scratch pattern smooths out, as it will alter the friction between the hone & bevel (feels suddenly 'slicker'). And when the edge finally gets apexed, you can feel the edge 'bite into' the hone a bit. That's an invaluable clue to pause, and look for the burr formation. If you see it, you can then move to another section of the blade and pursue the burr there.
 
I was able to feel the hone working the blade much better by using lighter pressure on the hone. I also slowed down as well and that seemed to help as well to feel the hone.
 
One thing you might also consider is the relationship of the guide rod to the stone. If you don't maintain that relationship from stone to stone the angle to the blade can change. When I attach the rod to the stone and tighten it with the screw I make sure the bottom of the guide rod is level with the bottom of the stone.
 
Yes I do that as well thallium.
However there is no guarantee that you are keeping the same angle regardless of the plane of the guide wires. The holes in the plastic hones would also have to be exactly perpendicular to the plane of the hone surface as well as the guide wire. And the bend in the guide wire itself can be a cause for misalignment. My background as a precision mechanical inspector primarily on missile guidance systems causes me to see many opportunities for misalignment but I discount them all because of the materials being used and the lack of need for such precision alignment.
I just make sure the hone is on a flat surface and the guide wire is parallel to the same flat surface across the length of the wire and call it good enough for the government...nowhere near "dead nuts" but I'm not trying for dead nuts and I doubt Lansky is either...the cost would be too high and the need for such precision is not there.

Thank you though...great input.
 
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