#31433 - 02/27/05 01:21 AM
Re: Doug's RSK and Lansky sharpener
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new member
Registered: 03/23/02
Posts: 54
Loc: ca
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Agreed. The Sharpmaker is the way to go. The simplest, easiest way to sharpen knives with minimum setup. Woks well with the baisc kit, but If you want to reprofile and get that extra final polish, buy the accessory diamond coated and extra fine stones.
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#31434 - 02/27/05 11:27 AM
Re: Doug's RSK and Lansky sharpener
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Veteran
Registered: 12/18/02
Posts: 1320
Loc: France
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now, you really got me confused ......
Looking at the Lansky instruction sheet, I found a schematic, showing "their definition" of sharpening angle : that's the angle between the sharpening stone and the blade. If I use the 17? slot on the Lansky tool (the finest, there is no 15? position), I will "sharpen" the side of the blade, not the cutting edge (I hope you understand.....sorry... my vocabulary is not adequate...) if I use the 30? slot, then it looks like the stone is really sharpening the cutting edge
?????????????????? <img src="/images/graemlins/confused.gif" alt="" /> <img src="/images/graemlins/confused.gif" alt="" /> <img src="/images/graemlins/confused.gif" alt="" /> ??????????????????
_________________________
Alain
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#31436 - 02/27/05 02:26 PM
Re: Doug's RSK and Lansky sharpener
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Old Hand
Registered: 08/28/04
Posts: 835
Loc: Maple Grove, MN
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I use the Lasky Sharpener, and the angle marked on the guides is included angle. If you use the 30 degree hole, if that was the angle of the stone to the blade, then the included angle would be 60 degrees! That's the edge of an equilateral triangle, and not even an axe would be sharpened that bluntly.
One thing you need to be careful of is that the blade is clamped down straight. If it's angled either way, then the bevels won't be even on both sides.
_________________________
- Benton
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#31437 - 02/27/05 09:05 PM
Re: Doug's RSK and Lansky sharpener
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Veteran
Registered: 12/18/02
Posts: 1320
Loc: France
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Preliminary statement : geometry and I (me ?), we said good-bye to each other a long time ago. The only thing I remember is that a right angle boils at 90? ... <img src="/images/graemlins/grin.gif" alt="" />
And now, you want me to understand geometry in english !!! Argh...... <img src="/images/graemlins/crazy.gif" alt="" />
I don't even know what's the 'included' angle ... Should I guess it's the angle made by the two sides (slopes ?) of the cutting edge ? <img src="/images/graemlins/confused.gif" alt="" /> (*)
So, I just took the Lansky sharpener and make a few measurements. Let's say the tool make a right triangle ABC, with the right angle being point C. When my RSK is positionned in the tool, the very edge of the blade (point A) is at 11cm from C. The 30? hole (point B) for the stone's guide is at (about) 5cm from point C. A bit of trigonometry (told you it was a long time ago : I had to look in an encyclopedia to get this right ... well, I hope it is .. <img src="/images/graemlins/blush.gif" alt="" /> ) : hyp = about 12 cm sin(a) = opp/hyp = 5/12 = 0.41666666 >>> a = about 27? so the angle made by the two sides of the edge is about 54?
If the edge of the blade was positionned exactly at the end of the tool, hyp would be about 10cm >> angle would be exactly 30?
Therefore, the larger the blade, the smaller the angle, using the same hole as a guide. So the angles indicated on the Lansky tool are just rough references, nothing more. For instance, the lowest position marked 17? is only to be used on razor style blades. Does the RSK qualifies for such a style ?
_________________________
Did I compute/understand something wrong ? Any math geak around here ??
TIA for correcting me.
________ (*) included angle = angle included between the two sides ! Is that it ? Did I finally got it ?
_________________________
Alain
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#31438 - 02/28/05 01:11 AM
Re: Doug's RSK and Lansky sharpener
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Veteran
Registered: 12/12/04
Posts: 1204
Loc: Nottingham, UK
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> That's 30 degrees (nominal) included angle or 15 degrees per side.
Thanks, that put my mind at rest.
I would have preferred to buy a Spiderco Sharpmaker but I couldn't find a UK supplier. The Gatco seemed to get the best reviews of what was available. I knew I needed something because I've failed at sharpening for many years. My RSK was well blunt after I'd applied a steel to it. <img src="/images/graemlins/frown.gif" alt="" />
I don't think the Gatco Edgemate Professional is as good as the Spiderco. The instructions weren't really adequate. It tells you to grind a certain number of times, with no mention of forming a burr. Also, the grip is poorly designed and doesn't, well, grip. I found it helps to put cardboard between the grip and the blade.
However, the stones remove metal alright and the system does help keep a consistent angle. I've got my RSK cutting arm hairs again so I'm happy for the evening.
_________________________
Quality is addictive.
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#31439 - 02/28/05 02:34 PM
Re: Doug's RSK and Lansky sharpener
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Enthusiast
Registered: 02/08/02
Posts: 312
Loc: FL
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I'd like to add my note of approval for the Spyderco Sharpmaker, I've used Lansky and EdgePro systems with good effect, but the Sharpmaker is by far the easiest to set up, use, and take down.
I'm amazed that it consistently puts a better edge on my knives than I can get with either of the clamp-type systems. Seems counterintuitive, but I won't argue with results.
I'd also like to reinforce:
- The use of the magic marker, especially when finding out what the danged settings mean
- Working to raise a burr (and being able to detect one with your fingers or eyes)
- Using a steel and leather strop to maintain an edge for long periods between sharpening
All these things work well for me.
Bear
_________________________
No fire, no steel.
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#31440 - 03/02/05 04:14 PM
Re: Doug's RSK and Lansky sharpener
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Veteran
Registered: 07/28/04
Posts: 1468
Loc: Texas
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I will second the comments on Sharpmaker. I used to have a Lansky and gave it away once I got a Sharpmaker and I'll never go back. Not that there was anything wrong with the Lansky... it's just that the Shaprmaker is a lot better. I will also second the comments about using a magic marker. I use a magic marker any time I am reprofiling, whether with the at home with Sharpmaker or in the field with a hand stone.
_________________________
Learn to improvise everything.
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