Lee Valley PM-V11 Plane Iron Edge Question

[Bob Coleman]

I have a question about the toughness of the edge of the Lee Valley PM-V11 plane baldes I hope someone can help me with. I put a PM-V11 blade in my #7 and used it flatten boards for the top of a candlestand I am working on. I hollow ground the blade to ~25 degrees and honed it free hand with an oil stone. When I went to use the same plane to joint the edges of the boards I noticed a ridge running down the middle of the board edge! When I removed the iron I noticed that the edge had chipped out slightly. The wood is cherry and there was a section with a knot and some pin knots.

Anyone else had this happen to them? Anything about my sharpening technique that would make the edge more prone to chipping? The blade was a joy to sharpen and use, unless I have to grind a lot more frequently when working on hard wood!

Thanks is advance
Bob

[Patrick Harper]

I don't have much experience with PM-V11, but some other tool steels tend to chip at low bevel angles. Due to the small grain structure, I wouldn't have thought that would be the case. Did you free-hand hone at 25 degrees as well? My A2 really likes about 30-33 degrees.

[john zulu]

Secondary bevel at 30 degrees. The edge is not lasting at 25....... That is what I do for my PM-V11

[Chris Hachet]

Secondary bevel at 30 degrees. The edge is not lasting at 25....... That is what I do for my PM-V11

Ditto here, I alwasy go 30 or a little higher.

Chris

[Mike Henderson]

If your plane is a bevel down plane, using a low bevel angle doesn't buy you much. The angle to the wood is set by the angle of the frog. The only limitation on the actual bevel angle is the relief angle to the wood. A 30 or even a 35 degree bevel angle gives you a sufficient relief angle and will give you a stronger edge on your iron.

Mike

[Curt Putnam]

I haven't had the problem with any of my PMV11 edges. The bevel down stuff is all flat ground @ 30°. But then, I haven't done any knotty cherry lately either.

[Richard Verwoest]

I have 2 of the chisels, 3/8" and 1/2". I have been chopping dovetails in Alder and have had the same issue. After chopping 3-4 sockets, the edge has crumbled and chipped. So I have to "grind" on 80 grit psa paper on a granite plate. I have been reserving my displeasure with these until I am done with this project. And hoping the issue would go away, but that does not seem to be the case. I have kept them at the original bevel, but may try to increase.

Hoss

[Jeff Ranck]

Is this a new blade? I can't imagine the same holds true for LV PM11 stuff, but for some new blades, the very end of the steel is a bit brittle from the heat treating process and sometimes you have to grind back a bit to get past the brittle stuff. Once you get past that, things settle down and everything is good.

I've never had any problems with the LV steels in this way, but I have seen it before in other contexts.

Jeff.

[Tony Shea]

I have 2 of the chisels, 3/8" and 1/2". I have been chopping dovetails in Alder and have had the same issue. After chopping 3-4 sockets, the edge has crumbled and chipped. So I have to "grind" on 80 grit psa paper on a granite plate. I have been reserving my displeasure with these until I am done with this project. And hoping the issue would go away, but that does not seem to be the case. I have kept them at the original bevel, but may try to increase.

Hoss

Interesting, I have also noticed my edges on my two chisels (1/4" and 3/8") to be very prone to crumbling and chipping. I decided to try these two chisels out after the rave over them instead of completing my LN chisel sets with these two sizes. I am really hoping this is just a temporary thing at the first 1/8" of steel due to heat treating but have yet to use them that much. My A2 LN chisels are just miles ahead of the LV PM-V11 in edge retention at the moment. And in all honesty I think I like the feel of LN chisels a little better in use. I have been holding off with my disappointment of them until I really get down to what I think should be good steel. Although I have not had any issues with LN chisels right out of the box. This is just my experience with their chisels and holds zero weight on my opinion of their tool quality, I admit to being a LV fan through and through.

On the contrary my bevel up blade honed at around 27* is holding up wonderfully in my shooting plane.

[Derek Cohen]

All new blades edges are vulnerable to chipping initially. Consider it an issue after you have honed a couple of times.

I compared PM-V11 at 25- and 30 degrees in a BD plane, and found that the latter was significantly longer lasting. 25 degrees works well (vastly better!) in a BU plane, but the higher bed of a BD plane places extra stress on the edge. Use 30 degrees in a BD plane (all steels).

Rule for chisels when chopping: do not go below 30 degrees. This is for all steel types. None cope with lower angles very well under this type of stress.

Regards from Perth

Derek

[Jeff Ranck]

Ado not go below 30 degrees. This is for all steel types. Derek

I've pretty much settled on 30 deg. for everything I do/have except for the BU planes. Those I'll fiddle a bit with depending on what I'm doing.

Jeff.

[Patrick Harper]

To simply my sharpening setup, I pretty much hollow grind everything at 30 degrees and hone at around 33 degrees. This goes for everything but specialty tools such as chisels that will only be used for paring.

[Richard Verwoest]

Just an update-I reground the bevel on the 1/2" chisel to 30 degrees, and added a micro bevel. For what it is worth, I use the LV MK II honing guide on granite with automotive finishing paper up to 2500 grit, then strop. 30 degrees holds up a lot better when chopping dovetails in Alder. I am a lot happier....happier than a camel on Wednesday, or even Tuesday in this case....haaaa

[Chris Hachet]

Just an update-I reground the bevel on the 1/2" chisel to 30 degrees, and added a micro bevel. For what it is worth, I use the LV MK II honing guide on granite with automotive finishing paper up to 2500 grit, then strop. 30 degrees holds up a lot better when chopping dovetails in Alder. I am a lot happier....happier than a camel on Wednesday, or even Tuesday in this case....haaaa

Glad it is working out! I love PMV-11.

[david charlesworth]

I have become more and more convinced that sharpness is more important than low angles.

I use conservative angles on my chisels and plane blades, and never have chips.

David