Quick review Narex "stubbies"

[Jim Matthews]

Marked "8110" these are all just under 7 inches long. (180 mm)

The blade portions seem near full length compared to my beloved Marples with Ash handles.

The clever engineering is in the handle, which is Pear shaped.

Behind the bolster, the neck of the handle has a conical taper.

The last third is a full 5 1/2" diameter, with a large flat aligned with the blade. (140 mm)

This isn't just to keep the chisels from rolling off the bench - it gives tactile feedback to the orientation of the cutting edge. The aligned flat came as a surprise - something obvious I had overlooked.

It's another of those "Why didn't I think of that?" moments.


I got them because of the cost (set of 4 delivered for less than $60 usd) and find them an excellent tool, because of the overall size and doorknob sized handles.



http://imgur.com/gallery/jpRbzes

[Jim Matthews]

The steel is marked "8110" which Narex refers to as Cr-Mn steel hardened to 59 HRc. The blades are coated in some sort of lacquer that Mineral spirits barely softened. (Although the solvent completely removes the screen printed markings).

https://www.narextools.cz/en/butt-chisel-8110x

The milling marks are uniform and quite deep.

It took a full ten minutes on my coarse Atoma diamond plate to get the largest chisel back flat.

Wire edges release easily between steps but this steel "feels" harder than my usual O1.

Grinding plate - Coarse India - Hindustan whatsit - Buffing wheel in about twenty minutes, front and back.

I also eased the lands which are sharp from the factory.

Pictures in this set illustrate relative size.

http://imgur.com/gallery/Cj2k0nt

[Andrew Pitonyak]

This gives a description of the steel

http://www.narexchisels.com/Narex_Chisels/Narex_Cr-Mn_Steel.html

They expected the "printing" to come off the chisel. They explain it above and also that they needed to print and not etch, very interesting.

Lee Valley claims that their O1 blades are RC58-60, so a similar claimed hardness. I think that O1 can be as hard as 65.

[Jim Matthews]

Further adventures in prepping new chisels...

15 minutes can save you...oops, wrong channel.
http://imgur.com/gallery/oNCF2Ce

Got to use my JSK Koubou designed pivoting arm grinding whatsit, too!

[Assaf Oppenheimer]

how does that jig leave a straight edge? wouldn't it curve the blade?

[Andrew Pitonyak]

how does that jig leave a straight edge? wouldn't it curve the blade?

Am I missing a picture of something that will curve the blade?

Sharpening on a grinding while will leave a curved surface on the blade. I refer to it as a "hollow" grind. It is easier to sharpen free hand if you sharpen this way. I sharpen most of my blades this way. I have NOT sharpened my mortise chisels this way.

Consider this thread:
https://sawmillcreek.org/showthread.php?214680-hollow-grind-japanese-wrong

Specifically, this post:
https://sawmillcreek.org/showthread.php?214680-hollow-grind-japanese-wrong&p=2232921#post2232921

Look at the third photo, especially on the left most chisel. You will see a shiny spot at the top and bottom of the chisel bevel. That is because there is a "hollow" concave grind on the chisel and then it was put on a stone so it only touches the ends.

Maybe these two:
https://sawmillcreek.org/showthread.php?267100-Hollow-grind-question
https://sawmillcreek.org/showthread.php?117436-Grinding-Nirvana

[Jim Koepke]

how does that jig leave a straight edge? wouldn't it curve the blade?

It appears some of the imgur.com images may have been replaced. Some of the images when clicking on next are news items that are more recent than the start date of this thread.

Unless two threads are getting transposed my recollection is someone showed a sharpening fixture that was side to side sharpening but was mounted in a way that it had a swinging action from a central point.

jtk

[Jim Matthews]

Imgur has some performance issues, this week.

I just checked and the links were active.

https://i.imgur.com/w5w77bJ.jpg

[Jim Matthews]

how does that jig leave a straight edge? wouldn't it curve the blade?

It's effectively "side sharpening". The entire edge is kept at the same distance from the fixed pivot point on a flat surface.

It carves an arc across the stone, to be sure, but all on a single plane. The get camber, the corners need to spend more time against the abrasive, or the abrasive must be concave (like Odate's crowning plates) or the steel must be tipped onto a corner for more grinding.


https://youtu.be/_Gl4Y--5C88

[Lawrence Burkett]

The way to understand the jig is to imagine an analog in free hand sharpening: you can trace any pattern on the stone (e.g., back and forth, side to side, figure eight). You'll end up with a flat bevel if you don't rock the blade. That's the same thing this jig is doing.