About Shooting Planes and Their Blades

[Derek Cohen]

I recently completed a little more blade testing, and I'd like to share my conclusions and the events that led up to them.


The recent comparison of the Veritas and Lie-Nielsen #51 shooting planes revealed poor performance of the O1 and A2 steels in the LN, and excellent performance of the A2 and PM-V11 steels in the Veritas. (For those that did not read the review, it is here: http://www.inthewoodshop.com/ToolReviews/LVShootingPlane.html).


One question remained unanswered in this review: "While these results were consistent, indicating that the LN A2 blades simply did not hold an edge as long as the Veritas blades, it did not inform whether the LN’s bevel down orientation was responsible for increasing wear, or whether the quicker wearing blades were responsible for the increasing extra effort on pushing the LN #51 plane. What I really wanted at this point was a Lee Valley replacement blade for the LN plane, either A2 or PM-V11. I had neither".


Observations from an earlier review


Two years ago I made a comparison of the LN #51, LN #9 (both dedicated shooting planes), and the Veritas LA Jack (a general purpose plane) (Link below). These three planes are different in significant ways. The #51 has a cutting angle of 45 degrees but with a skew of 20 degrees. The #9 and the LAJ both have square blades, but the LAJ has a low angle bed of 12 degrees (for a cutting angle of 37 degrees) and the LN a bed of 20 degrees (for a cutting angle of 45 degrees).


What was interesting about the results was that, while the #51 came out top by a mile, the LA Jack proved to be capable of a better performance than the #9. In part this was believed to be due to the higher mass of the LA Jack, and in part to the lower cutting angle. I now believe that there is a third factor.


LN #51 plus PM-V11


It was Rob Lee that offered me a PM-V11 blade for the LN #51. Here it is below flanked by the Japanese Smoothcut on the left and the LN A2 on the right. The Veritas Stanley Replacement PM-V11 blade is roughly between the two in thickness.


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/2_zpsf1edf896.jpg


I was warned that this blade does not fit a LN plane. On examination I discovered that this was due to the cut out on the LN chip breaker being set about 1/4" further back than on the Stanley and the Clifton chip breakers.


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/3_zps37fbf5e6.jpg


For the purpose of this experiment, I used the Clifton chip breaker, which was similar to the LN chip breaker in thickness. With this combination, and the frog moved forward, the LN #51 set up perfectly.


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/1_zps9bb7238a.jpg


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/4_zps605832bf.jpg


We returned to the same Curly Marri test board used in the Veritas Shooting Plane review, and the same procedure: sharpen blade and test the edge on end grain Radiata Pine. Aim for 60 completed shavings. Assess the performance subjectively. Photograph and test the edge on the Radiata Pine for objective evidence.


Results


As with the LN A2 blades, the PM-V11 was tested at both 25- and 30 degrees.


The results of planing with 25 degrees were very poor - I stopped planing after 6 shavings were barely completed. The plane was just not cutting, and the Radiata end grain test comfirmed this. After re-grinding and using the blade at 30 degrees, I tried again at 25 degrees. Results were the same. The PM-V11 simply failed at 25 degrees in the LN #51.


The results of the PM-V11 at 30 degrees were chalk-and-cheese. The #51 completed 60 shavings fairly well - not with the ease of the Veritas Shooting Plane plus PM-V11, but clearly so over the LN A2 blade. The LN A2 blade had been struggling from the halfway mark. The PM-V11 blade began to struggle about three quarters through the 60 shavings.


Photos of paring end grain Radiata Pine reveal the poor performance at 25 degrees ...


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/5_zpscf25df6f.jpg


... and the decent performance at 30 degrees ...


http://i13.photobucket.com/albums/a262/Derek50/Planes/LV%20planes/Shooting%20Plane/6_zps1dcdf7c4.jpg


Discussion


There are three conclusions that may be drawn from these results.


1. The first is that blade wear is correlated positively with bed angle. In short, the higher the bed angle, the greater the force imparted to the edge of the blade, and the faster the wear (by fracture). The lower bed of the bevel up Veritas creates a lower cutting angle (37 degrees), and this outlasts any blade in the common (45 degree) angled LN. This advantage remains even when the bevel in the LN is raised from 25 degrees (the only angle used in the Veritas) to 30 degrees.


A corollary is that the reason the LAJ was preferred to the #9 was primarily due to its lower cutting angle, and not simply its extra mass.


This is support for the belief that end grain is more easily planed with a low cutting angle, but the results also reveal that the blade life is longer with this configuration.


2. A second point is that any bevel down plane that is used for shooting will be expected to work significantly better with a 30 degree bevel over a 25 degree bevel. Interestingly, while LN do mention that blades may be honed at a higher angle, the LN #51 comes with a 25 degree bevel. I assume that this was because it uses a production blade common to the LN #4 1/2, #5 1/2 and #7 bench planes (my LN #4 1/2 arrived with a 25 degree blades as well).


A corollary here is that those that shoot with a BD bench plane, such as their trusty #7, risk rapidly wearing the blade. Get a BU plane for better shooting performance.


It must be emphasised that this assessment focussed on shooting planes and not bench planes. It is a situation analogous to a comparison of chopping versus paring dovetails. Shooting involves impact while planing is about abrasion. The results here are not to be interpreted that all BD planes will suffer with a 25 degree blade (although there is no advantage to using a blade at this angle on a BD plane).


3. The third conclusion is that the PM-V11 steel is more durable than A2 steel at 30 degrees when shooting. Its impact resistance at 25 degrees, as used here, on the other hand, was not as good as A2. In the testing of chisels (link below), all were used with 30 degree bevels as the test involved chopping end grain (dovetails). Here the PM-V11 was vastly more durable than A2. The simple recommendation is use 30 degrees on all chisels where impact is involved.


Regards from Perth


Derek




References:


http://www.inthewoodshop.com/Furniture/ShootingPlanesCompared.html


http://www.inthewoodshop.com/ToolReviews/FourChiselSteelsCompared.html

[Jim Koepke]

Thanks for all the work you must have put into this study.


A corollary here is that those that shoot with a BD bench plane, such as their trusty #7, risk rapidly wearing the blade. Get a BU plane for better shooting performance.

Been there, done that, bought one, though occasionally if one of my BD planes is closer at hand and it is only a few passes the BU shooter stays on the shelf.

jtk

[Chris Griggs]

You have too many shooting planes!!!:)

Cool analysis though. I do always enjoy the fruits of your shooting laboratory. Nice work Derek, your efforts are very much appreciated.

[David Weaver]

Always felt like all of the BU planes work best with 10 degrees of clearance on the shoot board so that the iron fails by wear more so than chipping. Anything around 30 degrees or a little less is still a but suboptimal for A2, and in truth, really for anything. The A2 just wears long enough to make it worth using that setup, whereas a vintage softer iron might not last long before the clearance is gone.

I never like looking down at the edge of an iron and seeing shiny glints from chips looking back at me. At the risk of sounding like a broken record, in my formative years, I tested a few irons by counting strokes and the irons that chipped first failed first every single time, even if the chipping was very minor. Not to mention, they leave lines on everything.

[Derek Cohen]

Hi David

I think that my testing has shown strong support for BU shooting at 25 degrees, even with A2 (Indeed, I have been using a LAJ in this configuration for many years without a problem. Lower cutting angle is better than a higher cutting angle). Even at 30 degrees, the BD plane with a common angle bed will chip its blades before the low angle BU plane. Note that I cannot make a statement about a BD with a low bed. I suspect that this will be closer to the BU plane.

Regards from Perth

Derek

[David Weaver]

I didn't have the same experience with the LAJ and 25 degrees (with any of the three offerings of LVs), but what little I shoot, I've always tried to maximize the sawing accuracy and minimize the shooting. I did think it held up well at 30 degrees, but with the minimizing of shooting, it may be that I was just pleased the iron wasn't looking bashed.

common bevel down bench planes haven't been a problem with a 35 degree final bevel, but using some older planes has been an issue in as much as the adjusters don't hold set as tightly or as well as newer planes, at least the couple I've used haven't, so I still have one premium bench plane.

In the last two projects I've done (4 kitchen cabinets/doors and a bookshelf and mouldings that was done entirely with hand tools, save four miter cuts), I have to admit I haven't shot a single thing, though. I will avoid it on anything I can, which leaves only the smallest things needing the attention of the shoot board. We all have our ways, I suppose.

But anyway, 35 degrees for the final bevel on the bench plane makes worlds of difference. Most BD bench planes with modern irons will work better set up as such even in face and side grain, let alone the bulldozing experience of smashing across endgrain.

[Jim Koepke]

Lower cutting angle is better than a higher cutting angle.

When it comes to shooting my shoulder will vouch for this.

In my experience the low angle also leaves a better surface on end grain.

Some of us still show our end grain in public.

jtk

[David Weaver]

Some of us still show our end grain in public.


How suggestive and promiscuous!!

[Jim Koepke]

How suggestive and promiscuous!!

Can't help myself, the ooohs and aaahs are intoxicating.

jtk

[Kees Heiden]

So, lower angle less wear. Does it also work like that at high angles? Does a 55 degree angle wear substantially faster then a 45 degree one in long or end grain?

[David Weaver]

A 55 degree angle plane wears faster than a common pitch plane in everything.

[Pedro Reyes]

.... the LN a bed of 20 degrees (for a cutting angle of 45 degrees).


Derek,

Thanks again for your observations.

Just a note, the effective cutting angle of LN's #51 is (due to the skew) lower than 45 degrees, somewhere around 43 or so I estimate.

I know there has been too much discussion around skew angles and rampped boards, I've given up, but just wanted to mention this.

/p

[Derek Cohen]

Hi Pedro

You are quite correct. Both the LN and the Veritas are skewed and therefore cutting a few degrees below that stated.

Regards from Perth

Derek

[Hilton Ralphs]

2. A second point is that any bevel down plane that is used for shooting will be expected to work significantly better with a 30 degree bevel over a 25 degree bevel. Interestingly, while LN do mention that blades may be honed at a higher angle, the LN #51 comes with a 25 degree bevel. I assume that this was because it uses a production blade common to the LN #4 1/2, #5 1/2 and #7 bench planes (my LN #4 1/2 arrived with a 25 degree blades as well).


I'm confused. These are Bevel Down blades so why would changing the angle make any difference? Are these installed upside down or something?

[Derek Cohen]

I'm confused. These are Bevel Down blades so why would changing the angle make any difference? Are these installed upside down or something?

Hi Hilton

It makes a difference to the longevity of the blade. A 25 degree bevel will fail faster than a 30 degree bevel on a BD shooting plane. The cutting angle is the same for both (as it is a function of the bed angle), so why use a lower, weaker cutting angle?

The same does not apply to a BU shooting plane.

Regards from Perth

Derek

[Hilton Ralphs]

It makes a difference to the longevity of the blade. A 25 degree bevel will fail faster than a 30 degree bevel on a BD shooting plane. The cutting angle is the same for both (as it is a function of the bed angle), so why use a lower, weaker cutting angle?


Ah makes sense, bit like a pig sticker then. So in theory one could match the complimentary bed angle, less a degree for some clearance to maximise the thickness of the steel behind the cutting edge?

[Chris Griggs]

Ah makes sense, bit like a pig sticker then. So in theory one could match the complimentary bed angle, less a degree for some clearance to maximise the thickness of the steel behind the cutting edge?

In theory, but in reality you need more like 10 degrees of clearance. 35 degrees is nice angle for BD planes to maximize longevity and still provide clearance.

[Kees Heiden]

10 degrees is not much when planing endgrain. I would shoot for 15 degrees just to be sure. Endgrain can bounce back quite agressively.

[Adam Cruea]

In theory, but in reality you need more like 10 degrees of clearance. 35 degrees is nice angle for BD planes to maximize longevity and still provide clearance.

I keep all my BD planes at 30 degrees except for the LN 51. That one I keep at 35 because the iron fails so quickly otherwise.

Nice write up, Derek. Perhaps when I have $65 burning a hole in my pocket or Rob runs another free shipping event, I might spring for a PMV-11 blade.

Don't suppose you have one of the new LV chipbreakers that you could swap in for that Clifton chipbreaker with the PMV-11 to see if it fits the LN 51? :D

[Chris Griggs]

I keep most mine ground at 30, I'll sometimes polish a higher micro bevel up to a total of 35, and think (anecdotally anyway) that for something like a smoother where you really want to avoid any sort of micro chipping that might cause tiny little lines it is helpful. Not a necessity by any means. Generally I think 30 degrees is a happy place for just about any blade. I generally don't like having anything other than paring chisels below 30 degrees. Even my low angle BU planes (block, shoulder, jack) I keep at about 30 just because I feel like it helps edge longevity, and the resulting 42-45 degree included angle works fine for me on end grain.

I may change my mind someday, and based on Dereks tests may mess with A2 at 25 degrees in my LA Jack, but for now that's what I find works best for me.