PMV-11 Chisel Performance

[Pedro Reyes]

Let me start by saying that I love, own and hold Lee Valley products in the highest regard. Their medium shoulder plane is perhaps one of the best tools I have ever owned, beautiful. As an engineer I appreciate all the thought that goes into their designs, which are so well executed. I have 3 of their shoulder planes (if bullnose counts), several chisels, block planes, the BU jack rabbet ( a marvel of a tool), skew rabbet. shooting, etc. and plenty of other ancillary stuff from them (sharpening, guides, marking, etc.)

But... (we knew one was coming). In a couple of instances I have had my PMV-11 chisels fail, I think all these instances were in construction lumber from a big box store. At first I thought that I should get a steeper micro-bevel on there and I did, but I still got the failure.

A science comment (force/area) more than a woodworker comment- construction lumber (SYP, Fir, Pine) a "softwood" is extremly though on tools because there is such a marked difference between early and late growth rings, this creates enormous pressure hence my failure mode, I get it. Chopping with a chisel, all the force is on only the small areas of the darker rings since the lighter rings are like butter, so I think I know what is going on, however an old Witherby or even newer A2 chisels don't seem to fail this way.

Any experience anyone can share?

IMG_6569.jpg

peace

/p

[Kent A Bathurst]

popcorn.jpg

I'm ready to go.

[Rob Luter]

I have a PMV-11 blade in my LV Shooting Plane. I find that it chips rather easily. I wind up sharpening it regularly.

[Patrick C Daugherty]

I do not mean to be a smart #$% here, but the answer is in your last sentence. You have chisels that work with soft wood. Use them. Save you PMV-11 chisels for other uses.

[Rafael Herrera]

What secondary bevel are you using? I'd keep going steeper until it stops chipping. My one A2 iron block plane, it kept chipping and I kept going steeper until it didn't.

Have you tried to round the edge with a buffer, the infamous "unicorn treatment"?

It looks pretty bad, you need to grind well past that to reveal undamaged steel.

I just saw a reply above. Why on earth is there a chisel in the market that fails when on pine? Buy a fancy tool, the gurus tell you it's "best" in some way, but at the end of the day you need to use some old tool to actually get something done.

[Jimmy Harris]

I'll be the first to admit that I'm probably wrong here, but judging from the size of that "micro" bevel (if I'm seeing it correctly), my guess is it looks like you ground your chisels on a bench grinder and they got overheated and lost their temper. And now your steel is super brittle.

[Cameron Wood]

I'll be the first to admit that I'm probably wrong here, but judging from the size of that "micro" bevel (if I'm seeing it correctly), my guess is it looks like you ground your chisels on a bench grinder and they got overheated and lost their temper. And now your steel is super brittle.

I don't think that is a thing- overheating resulting in brittle.

Although it's more common the other way (too soft), it's possible that the initial edge of the chisel(s) is too hard, and it will settle down after several sharpenings.

What Rafael Herrera said- keep grinding steeper until it doesn't chip. But also be sure to hone all the way past any chips in the edge as that will start the process over.

Don't really buy the "enormous pressure" thing. I use DF a lot.

[Rafael Herrera]

While waiting to not be selected for jury duty... How has the edge failed? By chipping or folding? I can't tell from seeing the picture on my phone.

[Mike Henderson]

You should probably contact Lee Valley. I have a set of those PMV-11 chisels and they work fine for me. Must be someting wrong with the ones you got.

Mike

[Andrew Hughes]

What I do with fir is cut the fibers with a slicing motion so the the edge isn’t flicked with the hard growth rings.
Even my Tasai chisels will chip if a prying motion is at the edge.
Its a slower process then chopping but worth the extra time when you see the surface left.
Good Luck

[Jimmy Harris]

I don't think that is a thing- overheating resulting in brittle.

Although it's more common the other way (too soft), it's possible that the initial edge of the chisel(s) is too hard, and it will settle down after several sharpenings.

What Rafael Herrera said- keep grinding steeper until it doesn't chip. But also be sure to hone all the way past any chips in the edge as that will start the process over.

Don't really buy the "enormous pressure" thing. I use DF a lot.

I think you're right, unless you were getting it WAY too hot and then quenching it. Which seems a bit far fetched to me.

But, looking at the photo more closely, it almost looks like the edge is bent, not chipped. I think I can see small shadows running parallel to the edge. Which might be cause by the steel softening?

The only time I've ever experienced chips in steel tools while working softwoods is when I'm working through a particularly dense and resinous knot. Those can absolutely wreck the edge of a tool. Otherwise, my biggest issues are keeping the tools sharp enough so that they don't crush the soft earlywood before they slice the denser latewood.

[Pedro Reyes]

I'll be the first to admit that I'm probably wrong here, but judging from the size of that "micro" bevel (if I'm seeing it correctly), my guess is it looks like you ground your chisels on a bench grinder and they got overheated and lost their temper. And now your steel is super brittle.

I don't use a bench grinder for anything other than lathe tools, sigma and shapton waterstone. The edge is not folded over, I had a wider chisel and both fractured, at least it's what it seems.

/p

[Pedro Reyes]

Thanks all for taking the time.

-edge is not folding.
-I hand sharpen, no heating
-there is a secondary, will confirm if 30 or 35

Patrick C Daugherty
I do not mean to be a smart #$% here, but the answer is in your last sentence. You have chisels that work with soft wood. Use them. Save you PMV-11 chisels for other uses.

yeah except when I need a specific size, I don't have Witherbys in all sizes. Plus, come on that is an incomplete answer, in theory it is a premium chisel and should perform at least as well as other "premium chisels"

Andrew Hughes
What I do with fir is cut the fibers with a slicing motion so the the edge isn’t flicked with the hard growth rings.

right, but I sometimes need to chop, again a premium chisel should not be that limiting.

Cameron Wood
...

Don't really buy the "enormous pressure" thing. I use DF a lot.

Don't mean to sound like a smart a$$ but wasn't really trying to sell that, it is a fact. If you lay on a bed of nails nothing happens if you lay on a couple of nails you'll get punctured, simply because pressure increased.

Rafael Herrera
What secondary bevel are you using? I'd keep going steeper until it stops chipping. My one A2 iron block plane, it kept chipping and I kept going steeper until it didn't.

Have you tried to round the edge with a buffer, the infamous "unicorn treatment"?

It looks pretty bad, you need to grind well past that to reveal undamaged steel.

I just saw a reply above. Why on earth is there a chisel in the market that fails when on pine? Buy a fancy tool, the gurus tell you it's "best" in some way, but at the end of the day you need to use some old tool to actually get something done.

This may be it, but I thought I was at 35 deg already, will check with the guide.

Rob Luter
I have a PMV-11 blade in my LV Shooting Plane. I find that it chips rather easily. I wind up sharpening it regularly.

hmm, their plane blades (PMV11 or otherwise) have not yet given me any unusual issues. I have their shooting plane but I have not used it on softwood yet, my trusty 5-1/2 with a hock A2 has not had issues with it tho.

Mike Henderson
You should probably contact Lee Valley. I have a set of those PMV-11 chisels and they work fine for me. Must be something wrong with the ones you got.

Thanks, I know they are top notch when it comes to CS and helping, not sure I am there yet, hence this post reaching out to see if someone had experienced anything similar. This has happened on two of my PMV-11 chisels, and they were purchased at different times, so I had subjectively ruled out "bad batch", but who knows, maybe. The one common denominator has been wood with disproportionately different hardness between rings.


/p

[Richard Verwoest]

I had this issue with a chisel also. I was chopping dovetail waste in Alder, and the edge would chip. This got better as I sharpened it over the course of the project.

[Edward Weber]

Just an observation but one of these threads about these particular chisels comes up way too often.
While some have had "good luck", in other words, tool working as it should. The number of post with folks having issues with them is far too many IMO.
If it was mine and I was able to, I would send it back.