Sharpening a MAC with Minosharp 15* Guide Rails

As a sort of general proposition, guide rails suck for any knife with more than minimal rocker, and/or belly, and/or that's 8" or longer. 

As to the rest of your sharpening, since I don't know what you're doing I won't comment other than to say if you don't know how and why to deburr, how and why to soak and flatten, etc., etc., etc., you may want to delve into the whole sharpening subject more deeply.   

Since I don't know what MAC USA did to resharpen your knife and won't comment other than to say they usually get high marks.

My suggestion is to decide whether you want to learn to actually freehand your knife or to buy some sort of gag or tool and jig to help you sharpen.  The Minosharp3 at about $80 works well enough to keep my daughter happy with her MAC Pro MBK 95 and may be good enough for you.

BDL

I have used the Fiskars with great results for the past ten (10) years, really want to try the MinoSharp three stone though.

It surprises me that Harold at MAC USA would let something go out not razor sharp, I've always had great service.
 

I don't want to get into the science of "bending burrs" and "deposit burrs," or even if there's a difference between the two. 

When you sharpen, you almost always create a wire, and the wire almost always bends and/or develops a deposit bead on the side not being sharpened.  The easiest way to feel it is to turn the knife edge up, then push your thumbnail gently up the face of the knife which was not being sharpened.  If you feel your nail grabbed even slightly as though running into a "hook," that's the burr.

Proper sharpening -- okay, sharpening the way I do it -- involves creating a burr than chasing it by getting it to move from one side of the edge to the other (called chasing).  When you can get it to do that with every stroke, your knife is ready to be deburred. 

If that makes sense, we can move on to the next level of refinement.

BDL 

mmm... I don't have a lot of experience sharpening and when I started I bought the very same minosharp guiderails you mention.

Not only that, but I also bought another cheapo one set at a more teutonic angle of 20* - the idea at the time was to put a final microbevel... silly me...

The minosharp thingy will give you an angle which is best described as "between 10* and 15*", the reason being that there's other stuff involved, notably the blade's width.

I would tend to agree with BDL (who gave me quite a few excellent advices in other posts, along with JBroida) that at the end of the game real freehand is the way to go but I'd say that those guiderails had helped me the very first times to get a feel of what ~12* really meant with wrist positioning and to start building that into muscle memory.

Remember to clip the guiderail at an angle so that the longer side is as parallel as possible to the actual edge, not the spine of the knife and to position it rather towards the tip than the heel.

BTW, dunno if this applies to you but I've had pleasant surprises from using the magic marker trick, as suggested by various experts in this and other forums.

also, i've found it immensely helpful when teaching others to be able to use an angle finding app (like a digital protractor or something like that).  Few people know what 10, 15, or 20 degrees look like.  My experience is that people either pick an angle MUCH lower than what they intend or MUCH higher.

+1 with Jon.

My usual advice is to get a protractor, some paper, and draw a three or four large 15* (or whatever) angles and put them -- flat and standing up -- around your sharpening station so you can look at them and compare your knife angle on the stone while you sharpen. 

If you can get hold of an electric protractor as well to help you picture what the knife should look like, so much the better.  Some guys put their stone in an articulated vise at the desired angle, and try to hold the knife horizontal as they sharpen.  Personally, I think that's weird but to each his own.

In your case, it appears you're already used to "clicking in" and letting the old angle on the knife control the new angle.  That's fine for ordinary sharpening but is also part of the process which results in inevitable thickening and NO GOOD for thinning.  So... if you do "click in" (whether consciously or unconsciously) part of the thinning process is going to be making sure you don't do it when you profile.

The Magic Marker Trick will help you a lot.  If you're taking ink off the edge within a couple of strokes, you're too obtuse.  If you take ink off the face of the knife way over the bevel, you're too acute. 

The Magic Marker Trick will help you with so much more, please use it.

BDL

Wow, how do you manage to get a burr on the 6000?!

Every time I move to that stone and switch to a "stropping" motion, the burr melts away at the very first passes and after that there's no way of reforming one (not that I really want or need to).

Maybe I should apply some more vertical force. But does it make sense to reform a burr on a 6000 after it's gone?

Quote:

Originally Posted by Rumenta 

Wow, how do you manage to get a burr on the 6000?!

Every time I move to that stone and switch to a "stropping" motion, the burr melts away at the very first passes and after that there's no way of reforming one (not that I really want or need to).

Maybe I should apply some more vertical force. But does it make sense to reform a burr on a 6000 after it's gone?

As to making burrs on high grit stones, its very possible and not that hard... even with a stropping motion.

Anyways, on to the necessity of burrs... make it once (on whatever your coarsest stone is that you plan on using that day).  Everything else is just refinement, cleanup, and burr removal.  That doesnt mean however, that you wont be forming or be able to feel a burr on your higher grit stones.  Just make sure its gone when you're done.

Thanks guys, I'm gonna give this 6k re-burring a try soon. (I just have to do a friend's knife, completely covered in rust and badly chipped edge: great chance to practice!)