Sharpening with MK !! Narrow Blade Honing Guide

[ChrisLBren]

Hey Group,

Now that my La Renommee build is finally under weigh its finally time to sharpen the beautiful set of Lie Neilsen chisels I received as a gift from my wife last year.  I own the Lee Valley MK Narrow Blade Honing Guide and a Japanese Water Stone 1000/4000.  I work primarily with Pear Wood.  I noticed in the instructions that you can set your honing guide to various bevel angle.  Is 30-35 percent the proper setting ? Ive heard this system is full proof - but these were very expensive chisels - so I want to make sure I don't screw them up when I sharpen them tomorrow.  Any advice is appreciated !

Chris

[grsjax]

Assuming that your intended use is doing fine shaping and smoothing with the chisels than 30-35 degrees is appropriate.  If you want to use them to hog out a lot of wood than a a larger angle might be better.  The finer the edge the better control for fine work.  For work requiring more force you want the edge to be supported by more metal behind it.

[Mike Y]

Would be probably easier to keep them on the angle that they already have from the factory (since these are fancy chisels, chances are they are properly sharpened already), adding a secondary bevel of 2 degrees or so.

Changing the angle will require to remove a lot of material, and the reason is unclear

[druxey]

Check the factory primary bevel. Keep it as recommended by Mike Y and add a secondary edge bevel.

[ChrisLBren]

Thanks for the advice - so the factory bevel is at 30 percent on these chisels.  So thinking I will clamp them in the Veritas system dialed to that setting and adjust the knob from 12 OClock to 6 OClock and then use the 1000 stone side of the stone to create the Micro Bevel and then polish with 4000.  And then flip over to remove the burr with the 4000 stone.  Does that sound about right ?  

[tlevine]

That is how I do it.  Between sharpenings, I also hone the chisel with a leather strop.

[Gaetan Bordeleau]

Could someone explain why they add a bevel?

[Mike Y]

It significantly reduces the surface that needs to be sharpened. Instead of a full surface of a blade contacting the sharpening stone, only a tiny strip in the front contacts it. Hence sharpening takes much less time. 

Rough sketch, red is the part that is actually sharpened and contacts the sharpening medium:

Maybe there are more benefits.

Edited December 16, 2017 by Mike Y

[Gaetan Bordeleau]

I would say it depends of the types. To keep it simple, let’s make a comparison with only 2 kinds; long and small surface blade.

 

Knives  few inches and more, usually have a bevel  and it is faster to sharpen only the bevel. In fact it is only the bevel which is sharpened.

 

Other types of  knives,  with much shorter  surfaces, like Cabinet makers knives usually do not have a bevel and all the angled surface is sharpened. There is no time saving to add a bevel on a small knife. Also it would be difficult to recreate a perfectly aligned bevel each time.

[Mike Y]

 

21 hours ago, Gaetan Bordeleau said:

Also it would be difficult to recreate a perfectly aligned bevel each time.

That is what the jig is helping to solve. I have a simpler Veritas sharpening jig, but even a simpler version works perfectly. The sharpening time decreased significantly. 

[Gaetan Bordeleau]

Mechanically is surely easier. I guess there are no laws to do or not to do a bevel. It could be like a personal preference.

I do not use any guide for sharpening, I sharpen the whole surface (for the small knives) and by hand it would be difficult to do a perfect bevel.

 

What are the advantages to do a bevel?

For a knife with  a small angle, the thickness of the sharpened edge would be smaller, making it a bit thicker would help to have a more stable edge.

Also, using a leather strap helps to realign the edge which when observed at magnification  have a slight S curve. Additionally, a leather strap is the finishing touch like using, let's say 25000 grit. And finally a leather strap will eliminate burrs.

 

Recently, I saw a sculptor in a show. He sharpened perfectly smooth and shiny a knife with a coarse electric bench wheel and to get rid of bur at the end he used  a 240 grit.

Results were amazing. He got good results using a light pressure.

 

There are hundreds of possible combinations  to sharpen a knife, we just have to find one which suit our needs.

 

 

[Mike Y]

Totally agree re knife, but secondary bevels are typically for chisels and plane blades - they have a larger contact surface when sharpening.

And there are way too many sharpening methods, all of them yielding a similar quality results So many personal preferences! 

[ChrisLBren]

Thanks for the advice everyone - didnt get much modeling done and have yet to sharpen these chisels.  My kids wanted me to build a Jedi Temple - so Ive been busy with that project.  Happy Holidays everyone !

[Seren]

Personally I would NEVER use power tools to sharpen quality woodworking tools.

The only place for a grinder (IMHO.) is to re-profile an old or badly worn item.

If you have quality chisels then I would bet that they are already ground to a good angle, they only need sharpening.

The tool for this is a stone, either water, or oil, depending what you have. Followed by honing with a leather strop.

I was taught to sharpen with a secondary bevel, then hone. The secret is to keep the back of the blade very flat when de-buring the edge.

[Trussben]

Chris,

 

I use a Worksharp 3000 model electric sharpener designed for chisels and plane blades. Costs about  $175. Comes with two glass plates and four grades of abrasive to stick to both sides of the plates, 100,400,1000,4000 grit. When I’m normally sharpening I’m just using the 4000 side and it takes the burr off the back with a separate piece of 4000 that it rests on. 

Has a rack that the back of your chisel rests on that has preset and repeatable angles set into it.

You can also purchase a leather hone plate if you want to go to a pure mirror finish, however I find the 4000 is plenty sharp enough for almost anything I do and only takes a few seconds to maintain silly sharp edges.

 

ben

[Bob Blarney]

A typical factory bevel for chisels is 25 degrees (not percent), but considering that pear wood is fairly hard, I would be inclined to go with a steeper angle.  This is easily accomplished by creating a secondary bevel to 27-30 degrees. But between you, me, and the mainmast, I would worry about a degree here and there.

 

As for sharpening rigs, there is no shame in using a fixture to hold the angle (I do). For a long time, I used a 12x12 polished granite floor tile, with strips of good quality (3M or Norton) silicon carbide wet/dry autobody papers that were fixed to granite with sprayed on contact adhesive (spirits of naptha will dissolve it), with grits from 400 to 2000.  I lubricated with Windex window cleaner. Now I use DMT diamond stones, but I think Trend diamond stones would be a better choice.  (I prefer to use diamond stones over natural stones because they never need flattening, although they will need occasional scrubbing to remove minute metal bits.)  For final honing, I use a leather strop with a polishing compound.  If you don't have a leather strop, try a piece of MDF with compound.

 

If an edge is severely damaged, I grind it on a white aluminum oxide wheel or a 1x30 silicon carbide belt (Klinspor).  You can occasionally dip the chisel in water to keep it cool.  You can also shove it through a piece of potato and then grind - the potato will absorb the heat, but don't cook it (or eat it).

[Gaetan Bordeleau]

TO BEvel OR NOT Bevel

 

Sharpening metal can be done by hand or by machine. It can be done fast;

 

1- Sanding a new blade on a metal sanding blade

 

Or it can be done slowly like :

 

2- Finishing the sharpening on a surface grinder  1/10000 inch at the time.

 

 

Sharpening can be done by hand. When a small refresh of sharpening is needed :

 

3- begining with diamond stone up to about  # 1000

4- to water stones up to 8000. It can be even higher with porcelain but the difference is minimal to the use. To finish in beauty; some passes on a leather strop is use  to eliminate burs.

5-  different additives  with various grit# can  help to increase the finish.

 

The same job can be done faster mechanically or when a major regrind is needed.

 

6- Different kinds of abrasive wheel can be used depending of the intensity needed

7- Grinder with an adjustable angle is very helping to keep the blade without moving. Right side white abrasive, left side diamond wheel. Diamond are on the side of the wheels to have a flat surface. Because if diamonds were on the front of the wheel, the surface would be curved making the job harder to do.

8- For the finishing, different solutions more aggressive to begin and softer to finish. Felt wheels  or cotton wheels with compounds. To clean these kind of wheels,  I use sandpaper with a backing of wood and get rid of polishing compounds and at the same time it does resurface the front of the wheel

9- Leather wheels, hard rubbers

10- (Left side, little table to cut metal) right side 3M wheels, another kind of porous artificial rubber, I like this one very much, 3M made a very good job with this one. This is the best one for mirror finish, better and faster than felt or cotton wheels.

 

Now the question to ask ourself is why would we add a bevel. In fact I think it would be better to ask ourself is where would we need a bevel?

 

11- Let’s suppose I want to make a turning knife. I will use O1 steel, tool steel, .25 X 1 inch and I will cut a 1 feet lenght. The cut will be at 90 degrees. If I sharpen the end and get rid of burs I will get a scraper, very efective to bring a plank straight., but it would be prererable with a thinner blade

12- To turn this scraper into a blade, I just need to put a bevel at one end of the blade.

13- To sharpen a drill bit, I use a drill bit holder (photo 5)

14-  A milling cutter with a bevel? No it is more a relief angle wich is often added  to help to reduce friction with metal

15- On the last picture, we can see on the left 1 of the knife that I prefer. Even if it is a knife, there is no additional angle close to the edge. This knife cut extremely well.

 

In my opinion, for wood knives with narrow blades, there is no needs to a  second bevel. By example if a cutting angle of 25degrees is made, adding  a secondary bevel of +/- few degrees will absolutely not change anything in the cutting properties. We could try with a 25 and 30 degrees blade and very good is the one who can feel the difference.

 

For the long blades, it is different. The 2 sides of the blade thickness have 1 angle and 1 of the reason to save time, a bevel is added. To give an example. Few weeks ago I did grind the knives of the jointer with the surface grinder. Blades are about 6 inches long. There is a bevel on the blade. To sharpen I only need to sharpen the bevel. The rest of the side of the angle does not need to be sharpen because his single purpose is to hold the blade. By grinding the bevel only; it saves a lot of time. To sharpen just the bevel of the blade takes by example 2 minutes. If I would grind the complete angle, it would take 2, 3 or 4 time longer.

 

On the contrary with a narrow blade, if you sharpen the complete side and then you add the sharpening of a bevel, it will take much more time and you will risk, if you do not use a guide, to run the previous job. But if you only grind the bevel and not the complete side, then you could save some time. But because  a narrow blade has by definition a  very small area, there is not much time to save…