New narex chisels

[Mike Givney]

I picked up the set of nerex mortise chisels from lee valley and threw in the 1/8 inch for good measure. At $10 bucks for the little guy, it's definitely worth it.
I had some big mortises to chop in red oak so, trial by fire, I started out with the 1/2 inch. Half way through the first mortise the edge was broken and ragged. So, with a bit of disappointment I went to the stones and put a new edge on it and then a new bevel. Back to the wood and it chopped the remaining mortises like a champ. By the end of the session I actually found myself becoming a fan ( i'm used to pig stickers that were made before there were cars).
So, my question is; Is having to regrind new chisels common ? And, what would cause a weak original edge on what turns out to be a perfectly good chisel that performs as well as some of my old ones?

[Harlan Barnhart]

I suspect that the "skin" of your new chisel wasn't hardened properly. I've heard of this before. Just grind a new edge and you should be back to the good stuff.

[Matt Kestenbaum]

I had a similar effect when I first got my Ashley Iles bench chisels from TWW...I polished up the backs and put a micro bevel on them and started to pair some cherry. I was shocked to see the edge nicked up, but after lightly establishing a new bevel (and removing those nicks) on the grinder I have been very, very happy with their edge retention. Seems like the tougher steel was not yet exposed when they put the factory bevel on them.

[David Weaver]

Is having to regrind new chisels common ? And, what would cause a weak original edge on what turns out to be a perfectly good chisel that performs as well as some of my old ones?

yes.

Presumably decarburization (the carbon migrating from the steel surface to the atmosphere when the chisel is heated).

[Salem Ganzhorn]

As others have said this is fairly common. I got lucky and none of my narex mortise chisels have required regrinding. I hope yours will now hold up as well as mine have. I _really_ like these chisels!
Salem

[Mike Henderson]

I had the opposite problem with a Henry Taylor carving gouge. The first time I used it, the edge chipped badly. But after I re-sharpened (and ground back the edge) it was a great tool. In my case, the edge was too hard.

Mike

[Zahid Naqvi]

That's good to know, I have a set of these too but have not put them through any serious exercise yet. I'll keep a watch on this effect now.

[Jim Koepke]

A Swan 3/8" bevel edged chisel of mine did this for the first few times it was sharpened.

It was bought as used, but maybe it wasn't used much.

jtk

[Jessica Pierce-LaRose]

You did grind a steeper angle on these before starting, right? Mine came with a 25 degree bevel from the factory. Makes grinding a secondary bevel quick and easy, but I wouldn't start mortising red oak with an angle that low. (You don't say, but given you sound like you have some familiarity with this stuff, I'd assume you did, but it was the first thing that sprung to my mind.) I thought Narex tempered their chisels in a one step process in molten salt from what I'd heard; I wonder if that has any bearing on decarburization?

[Mike Givney]

I put a 35 degree micro bevel on with a veritas mk 2 jig. Just a quick couple of passes. The chunks that came out of the edge went well behind my starting bevel. That being said, I just came up from the shop after an hour and a half of mortising (elbow told me to knock it the heck off!) and the chisels performed flawlessly. Tried a couple of the rest of the set and they were fine. You know how it is... You drop money on some tools that you're not convinced about and they fail right off the bat. Sick feeling in the gut. But, with this chisel, i'm going to call it good. Hey, part of the fun of this neander stuff is playing with your tools, right?

[Jessica Pierce-LaRose]

I figure you did, Mike. I haven't had any problems with mine yet, but my secondary bevel was on the large size.

[Nelson Howe]

I'm interested to read this. I had the same problem with one of mine in pine and sent it back. Lee Valley couldn't have been nicer about replacing it. I feel a bit sheepish, though, if all I needed to do was a bit of grinding. It seems like it might be helpful for them to be able to suggest regrinding, and yet I doubt they would want to publicized that a product may not be quite right out of the package. The rest of the bunch have been fine, and I ordered the 1/8" to fill out the set.

As always, great service from Lee Valley.

Nelson