Replies

1. 
   JohnMcPhail | Jul 08, 2011 08:05am | #1

   Not a pro but...

   I'm not a pro or anything...

   My pocket knife can cut a hair and I don't think of it as razor sharp. Likewise, all my kitchen knives. IMO there are quite a few degrees of sharpness beyond cutting hair, and even beyond razor sharpness.

   I feel that if I make my tools as sharp as I am able ( I use an 8000 finishing stone ) I will have more time until performance is unacceptable, better cutting with less effort, more accuracy, and less work overall. My end grain work will be good the first time more often, and require less rework ( and less opportunity to mess things up ), tenons will look better, thinner shavings and less waste, etc. Statistically everything will be improved even if it's only a little bit, including my process.

   I also use the mirror-finish as a gauge - I can tell by looking when I need to hone again. It's my visual indicator.

   I like 'em shiny! :D

1. 
   CedarGroves | Jul 08, 2011 03:53pm | #3

   Most pros don't think they are either..

   I certainly agree there are degrees of sharpness above "shaving hair", but it seems there are few tests to quantatively measure how sharp my tool is... generally that leaves me with the shaving trick or paring some end grain on pine.

   And again, not all tools need to be at the same level of sharpness either... I take much more care sharpening my carving tools and paring chisels than I do with, say, my scrub plane iron. It depends on the task. I feel that speed when sharpening is important - if it takes too long or is too difficult I will be more likely to put off sharpening my tools and make due with dull ones, creating safety risks and reducing the quality of my work. This is the reason I learned to sharpen freehand and only bring certain tools up to "maximum sharpness" - saves energy and lets me spend more time working, not sharpening.

   My gut tells me the more polished your edge is, the lower  the friction coefficient between tool and material will be and severing the fibers more cleanly and efficiently will make work easier. I was just curious to see how others approached the issue.

   I like your tip about using the mirror finish as an indicator - thats a keeper.

1. 
   JohnMcPhail | Jul 08, 2011 04:20pm | #4

   Agree

   Interestingly ( to me ) I am moving to freehand from jigged scary sharp, and I agree with you, it improves the sharpening experience and makes it easier to "stay caught up". 

2. 
   Metod | Jul 08, 2011 09:01am | #2

   Sharp

   "am I going to see a significant improvement in cutting peformance/edge retention if I sharpen to a higher grit before stropping?"

   It is hard to tell from miles away what 'are you going to see', if you you try it both ways. Of course, it might take you another 10 minutes...

   Metod

3. 
   mvflaim | Jul 08, 2011 09:28pm | #5

   For me, I don't care how "sharp" a blade is as I am about what I'm actually producing with a sharp edge. I'd rather take 30 seconds and sharpen a blade to cut the way I need but may have to sharpen it every other day, versus spending 30 minutes sharpening a blade that I won't have to touch for a week. 

   The end result of your work is that no one cares how sharp your blade was.

4. 
   roc | Jul 08, 2011 11:03pm | #6

   .

5. 
   roc | Jul 08, 2011 11:18pm | #7

   For Me Woodworking Is Just An Excuses To Sharpen

   Dealing with the F . . . . ing spam filter is turning into a full time job

   PLEASE DELEAT THE SPAM FILTER  ! ! ! !

   IT IS EASIER TO JUST IGNOR THE SPAM THAN TO TRY TO REPOST AFTER ALL THE 

   B  S

   I just learned what triggered the spam flopper.  I copied a link to a thread in THIS FORUM.  That's brilliant.

   To use the coarse stone and then to strop with green rough is the equivalent to sharpening a rake or a comb.  The points are sharp but there will be dull places in between the points.  The surface left by the edge will be a mirror of this situation; minute grooves and minute rough high areas between them.  The disadvantage of doing this is more power is required to push the blade through the material.  More heat.  More heat could even mean the edge breaks down and dulls sooner.  Some types of wood are so hard this many be quite significant and some grain will tear out with a blade like this.

   I can not emphasize this enough : FOR A PLANE BLADE EDGE IT IS A MISTAKE TO STROP IT.  STROPPING BLUNTS/STEEPENS THE INTENDED SHARPENING ANGLE AND RUINS THE GEOMETRY OF THE EDGE.  A chisel you can strop because you can vary the angle as you move the chisel.  A plane blade is fixed so the sharpening angle must be fixed to achieve consistent intended cutting characteristics for the kind of wood you are cutting with the plane blade.

   The coarse sharpening to form the basic edge is what takes the most time. A pass or two on the progressively finer stones takes very little time in comparison. I always go to at least four thousand but almost always to eight thousand and for finishing to fifteen thousand just "because I can". Here is my thing :

   Interesting to look at: I find I can literally shave curls off a single hair. I recommend taking a jeweler's magnification visor and looking at this "shaving" situation. The blade can be made to, with very little extra effort, be so sharp that the blade is sliding down the length of the hairs and taking curls off but not necessarily cutting the hair in two. That is what happens when I have an off day at my sharpening.

   When I am really on my sharpening game the hair takes one look at the edge and gets so scared that they pull themselves up by the roots and run away before the blade gets to my arm.

   : )

   And a thread of possible interest :

   you have to enter this into your web browser manually since the spam flopper is so helpful.  Enter http then copy and paste the following address to get to an old thread in this Knots forum

   ://forums.finewoodworking.com/fine-woodworking-knots/hand-tools/testing-sharpness-high-angle-blades

1. 
   RalphBarker | Jul 09, 2011 09:58am | #8

   spam filter

   Roc, more people need to gripe about this in the Feedback section. I was told back in March that it would be removed, but it is obviously still in place.

2. 
   CedarGroves | Jul 09, 2011 10:19am | #9

   Great Action

   Maybe its just me but I do not consider a 1200 grit stone to be a "coarse" stone... IDK I just always had a mental divider where everything below 800 is coarse, 800-2000 fine, 2000+ extra fine. Not that it matters, I understand what you're getting at.

   The surface left by the edge will be a mirror of this situation; minute grooves and minute rough high areas between them.  The disadvantage of doing this is more power is required to push the blade through the material.  More heat.  More heat could even mean the edge breaks down and dulls sooner.  Some types of wood are so hard this many be quite significant and some grain will tear out with a blade like this.

   I agree 100% - I had some highly figured African Mahogany I was using for a display case that gave me all sorts of problems with tearout and the utter destruction of all my edged tools.... it was like a sharpening apocalypse when I was done with that thing and I still had to scrape/sand significant portions of it to get a good finish. Needless to say, I lost money on that job.

   But I disagree with you about stropping plane irons. I have heard some folks don't strop at all for fear of altering their honing angle, others strop relentlesly with powered wheels and the like.... I feel I fall somewhere in between. I have seen the ill-effects of stropping too much, i.e. putting unintended back-bevels on tools and rounding the cutting edge. But I also feel that it improves the quality of my cut, regardless of what tool I am using.... probably because I'm not polishing my blades to a high enough extent as you pointed out.

   I think the bottom line is I need to quit being such a miser and just spring for the stones I need lol.