A tale of two planes

Lie-Nielsen has benefitted the entire woodworking community by providing bench planes based on the venerable Stanley Bedrock designs.  The Record company provided bench planes that were clearly based on the Bailey patent system.  Interestingly enough, Garrett Wade Company also became involved in the “Imitation is the most sincere form of flattery” business when it offered the Paragon Plane.  The Paragon brand was identified as a “Premium” plane and carried a reasonable, but somewhat higher price than its competitors.

I had pretty much forgotten about the Paragon, until a friend of mine gave me one that he had purchased when Garrett Wade first introduced the line.  I knew that I had seen that design before, but where?  It didn’t take long for me to identify the design as that of the Millers Falls Type 4, that was produced from 1955 to 1966.

The Millers Falls plane was made in the United States, the Paragon in England.

The unique, two-piece lever cap, patented by Millers Falls was incorporated into the Paragon.

While the cheeks of the plane are a little higher on the Paragon, the similarities between the two planes are striking.  The M-F used Padauk for the knob and tote.  It appears that the Paragon also uses the same specie with a little different finish. Note the “upright” design of the totes.   The massive adjuster nut is common to both planes.

Both planes are excellent in performance.  But, I’d have to give the edge to the M-F.  The casting, machining and plating just seems to be a little better.  But, in fairness, the adjustments on both are smooth and with minimal lash.  Either one of these smoothers would be an excellent addition to the shop.

Dedicated No. 4 1/2

left: The Dedicated 4 1/2 - probably a type 17 - right: a type 11 No. 4 1/2 fitted with a new cryo blade

The 4 1/2 on the left in the above picture came into my possession several years ago.  My guess is that the main casting is a type 17.  It is noticeably heavier than the type 11 on the right.  It’s hard to understand why a wartime casting would be heavier as the US was looking for metals for armaments.  Some folks have speculated that Stanley was beginning to “feel the heat” as American GI’s came in contact with the classic British infill planes built by makers like Norris and Spiers.  But, the truth is we will probably never know the real reason. 

In any event, I decided to dedicate this baby to the sole purpose of smoothing highly figured wood, as in everyone’s favorite, curly maple.  Anyone who has ever tried to plane a piece of curly maple knows that it is about as tough as it gets.  First and foremost, a cutting angle of 45 degrees simply won’t get the job done.  So in order to raise the cutting angle, I decided to back bevel the iron by 17 degrees (give or take a degree).  This puts the actual cutting angle up to 62 degrees, which is about as high as can be achieved before incredible “chatter” sets in, due to the thin section of the Stanley iron and chip breaker. 

17 degree back bevel

The next step was to ensure that, while taking the thinnest possible shavings, the plane left no “tracks”.  So, the main bevel of the iron was gently crowned.  I’m “guesstimating” that the crown is something like .0015″.  If I were more of a scientific woodworker, I would have measured it.  But with me, most of the time, the right brain wins. 

The iron, "gently" crowned

Then it’s time to put the chip breaker back in place.  But wait!  Throw out the old notion that the chip breaker should be as close to the cutting edge as possible (sorry Gramps).  The back bevel disallows this.  Plus, since we’ve raised the cutting angle, we’ve effectively rendered the chip breaker useless, as far as “breaking” chips.  It does, however, still add mass, helping to minimize vibration. 

chip breaker set well back from cutting edge; 1/16-3/32"

The frog has been moved forward to create a mouth opening that is not more than 1/32″.  This minimum mouth opening is what, in fact, “breaks” the chip. 

Minimum mouth opening - a gnat couldn't crawl through it

It becomes immediately obvious that raising the cutting angle increases the amount of energy required to do the work.  This was one of the facts in my decision to dedicate this one plane to smooth high figure stock.  It won’t be much good for walnut or pine, but it will produce the beautiful, glassy surface that can only be obtained by sheer cutting. 

the objective - a highly reflective, glassy smooth surface on curly stock

Back beveling bench plane irons

Recently, a lot of folks have asked me what my opinion is about back beveling bench plane irons.  I’ve tried to be courtesy as I explain to them that this is like asking a theologian about the number of angels you can comfortably seat on the head of a pin. 

Back beveling seems harmless enough.  But, in fact, there are a number of things to consider before you do anything other than develop a bright, mirror-like, flat (yes, I said FLAT) surface on the back of your bench plane irons.

Just as an aside; many of those asking for my opinion are folks who are not happy with the performance of their bench planes.  My first response to this is to ask them if their irons are sharp, really sharp.  It still amazes me how many people, experienced woodworkers, have never learned to sharpen their tools.  Sharpening is THE gateway skill.  So, for the sake of argument, I’m assuming that your irons are SHARP!

WHAT IS A BENCH PLANE?

There are two types of planes.  The BLOCK plane iron is seated with the bevel pointing up, toward the user.  The BENCH plane iron is seated with the bevel pointing down, away from the user.  In most cases, bench planes will be fitted with a chip breaker.  The bedding and cutting angles on a block plane are not the same.  The bedding and cutting angles on a bench plane (unless a back bevel is employed) are the same.

Block plane with bevel up

Bench plane - with chip breaker and bevel down

PLAYING THE ANGLES

If you’re going to be serious about hand planing, you have to be aware that there are a number of angles which determine cutting efficiency.  The plane body itself provides the BED ANGLE.  When we talk about the iron we have to consider the INITIAL (ground) ANGLE, THE SECONDARY ANGLE and the BACK BEVEL, if one is to be employed.  The sum of all of this information is the CUTTING ANGLE.

PERFORMANCE

What is performance?  How are you going to use the plane?  Will you be using the same plane while working various species of wood?  Will you be using the plane for initial truing?  Will you be thicknessing with this plane?  Will you be using the plane for smoothing the finish surface on softwoods?  Do you want the ability to vary shaving thickness?  Is your goal to remove the thinest possible shaving?  Will the plane be used to smooth highly figured stock, such as curly maple?

Well, if your answer was that you want to be able to smooth highly figured stock, then continue reading.  If you were answering yes to the other questions, keep the back of your iron flat and polished and have a nice day.

UNDERSTANDING THE CONVENTIONAL WISDOM

Conventional wisdom is based on the collective experience of many people who have separately accomplished the same or similar tasks.  In the case of planing wood, this conventional wisdom has been developed over, at least, fifteen hundred years.  And the conventional wisdom is this; when using a bench plane, a forty-five degree cutting angle provides the best overall performance over a broad range of wood species and job requirements?

Roman plane - wooden body - "shod" in metal - single iron set at 45 degrees

WHY DOES BACK BEVELING CHANGE THE PERFORMANCE CHARACTERISTICS OF THE PLANE?

In a word, back beveling changes the CUTTING angle (some folks like to refer to this as the attack angle).  It has long been known that optimal cutting angles vary, depending on the wood species being planed.  For example; soft, straight grained species like redwood or cedar are best planed using a low cutting angle, something between 35 and 40 degrees.  Highly figured hardwoods like curly hard maple need to be planed using a cutting angle that could be as high as 90 degrees, but 60 to 65 degrees seems to provide the best performance.

KEEP BACK BEVEL LENGTH TO AN ABSOLUTE MINIMUM

After you’ve determined your new cutting angle (cutting angle minus bed angle equals back bevel), you’re ready to start honing your back bevel.  Remember, the back bevel really doesn’t need to be any longer than the thickness of the maximum shaving you intend to remove.  1/64 of an inch is sufficient.  Making the bevel length any longer than this creates two potential problems.  First, if you should want to eliminate the back bevel at some point, you’ll find that you need to waste a lot of stock in order to re-establish a true single bevel.  Second, back bevel length actually determines the position, and subsequent support (strength), of the cutting edge (arris).

INCREASED EFFORT

One of the rules of the woodworker’s universe is this – increasing cutting angle means an increase in required effort.  In other words, you’ve got to work harder to remove a shaving of the same thickness as you increase the cutting angle.  So the logical conclusion is that you should expect to keep the shaving thickness to an absolute minimum. 

I, like most other hand planing fanciers, recognize the therapeutic value of removing “whisper” thin shavings and leaving a “glass-like” surface.  But, if I have to take a 1/4″ of twist out of a board, I’d like to remove the thickest shaving that I can, without having a heart attack, of course.  So I won’t be putting a back bevel on anything but my smoothing plane.

VIBRATION

As cutting angles and effort increase, so does potential for vibration or “chatter“.  You may find that the chip-breaker needs to be bent back in order to provide more “purchase” on the iron.  Yes, one of the things that the chip-breaker does is to dampen vibration, especially in thin irons.  It’s interesting to note that many very expensive smoothing planes have no chip breakers.  Their performance depends on the use of very thick irons and very small mouth openings.

Small smoother by Wayne Anderson - note the absence of a chip breaker, the high cutting angle and the incredibly thick iron

DEDICATED PLANES

If you find that back beveling helps you in working with certain species and figures, by all means, do it.  But…chose the plane (or planes) that you’ll use and dedicate it (or them) to that purpose.  An alternative solution, is to have additional plane irons that are back beveled to provide a range of cutting angles.  It’s not a bad idea to use a “magic marker” to indicate the cutting angle on the iron. 

A FINAL THOUGHT ABOUT CHIP BREAKERS

Gramps would tell me to set that chip breaker as close to the cutting edge as possible.  And, generally, like all things that he taught me, that is true.  However…when removing very thin shavings, the contact point between the chip breaker and the iron, if not perfectly seated, can easily become clogged.  This is especially true when a back bevel is employed.  There are two simple solutions to prevent this:  First, make sure that the chip breaker has been undercut and honed dead flat across.  This will insure constant contact between the chip breaker and iron.  The lead outside surface of the chip breaker should be smooth and free of any nicks.  Second, set the chip breaker well away from the trailing edge of the back bevel (1/64 – 1 /32″).  Remember that the back bevel itself will actually begin to “roll” the chip before it ever comes in contact with the chip breaker.

Well, enough talk.  Happy planing!