Introduced in October of 1943 many aficionados do not consider the Third Pattern Commando knife a Fairbairn Sykes. By this time the design had mutated to something quite different, sharing only the format of a seven inch double-edged blade. The knife in this photo is an early one fitted with a heavy forged blade of the Second Pattern style. For collectors, Third Pattern knives with heavy blades are knife more desirable.  The most desirable of all are, of course, those with Wilkinson Sword Co. etchings. 

The Third Pattern is easily recognized by its ringed alloy grip. This design is attributed to the William Rodgers firm. The handles were cast in a gang mold in quantities of four at a time. Each mold cavity left its own embossed number on the casting. This number appears near the top of the pommel. Quite often later post-war knives do not have this number. The quality of the castings is generally very good. The handles had the mold parting marks removed and they were then copper plated. Most of the handles were finished black although some were nickel plated. Some people prefer the ergonomics of the Third Pattern grip. Others say that it ruined the balance of the knife. Truth is, it was the introduction of thin blades that really ruined the balance, not the change to the grip.

As the heavier blades were used up and steel became scarcer, the blades
were forged thinner and more coarsely finished. Many of the knives have rough grinding marks visible through the black finish applied to the blades.
The later production cross guards were also stamped of thinner stock and their fit to the tang was often quite sloppy. These poor quality knives were clearly not produced by Wilkinson Sword Co, but by other firms who had gained war-time contracts. One production figure that I found for WW-II Third Pattern knives was over three hundred fifty thousand. If that number is true then I suppose it might help explain the loss of quality.  Wilkinson Sword Co. continued to turn out quality F~S knives like the one shown below. Up until the closing of the factory you could order a knife in either black chrome or nickled finish.

Illustrated below is a thick bladed war-time third pattern knife. While many were critical of third pattern knives, those with the heavy blades were and still are, excellent fighting knives.

The top knife (following photo) is clear proof that even a thick bladed knife is not indestructible. It has been broken and shortened considerably.This is one of the rare knives that is stamped around the pommel FR693. Beware, there are many fakes with this marking coming out of India it would appear. They can be picked out by their broad blades, with poorly defined centerline ridge and clumsy, thick leather sheaths. I have included one of these in the post-war section.

Through Thick and Thin:

Third Pattern knives can be readily divided into two basic categories, those having either thick or thin blades. There is some speculation that all of the thick ones were trickle down from the remaining stock of Second Pattern production. I doubt this theory is totally correct but it is a possibility because there are also some P-2 knives with thicker or thinner blades. While I am on this topic I want to discuss the urban legend about the triangular flats where the blades enter the guards and the difference in fit between P-1 and P-2  or P-3 guards. Note also the copper flashing on the alloy handles which is often mis-represented as being a brass handle.

Urban legend says that the flats were created during the“drawing” process involved in forming the blades. This is simply wrong. The blades were forged, not drawn. Wire and tubing are “drawn” but not knife blades. Another legend says that the flats came from the “clamping fixture.” What clamping fixture? Undoubtedly the guards were stamped from sheet steel,
along with the square hole for the tang. If you have never had an F~S apart you would not know that the tang near the guard is a flat with rounded corners in cross-section. Eventually it transitions to roughly-round, and finally to full round where it is threaded for the top nut. The infamous flats on the blade are simply the way its thickness was reduced to permit it to enter the fixed size hole stamped in the guard.

With the original P-1 design, the square shank (ricasso) on the First Patterns neatly hid the square hole in the guard. I also believe that more time was taken in fitting the guards on the P-1s. As time became scarcer, and manufacturers needed to add less skilled workers, some of the precise fitting slipped by the wayside. When the tablet ricasso was done away  with, the corners it normally covered were left exposed. Unfortunately these gaps allowed dirt, blood and other fluids to enter and perhaps cause corrosion in an already weak area. Of course the thinner the blade, the bigger the gaps, plain and simple.

There are several different inspectors’ stamps that show up consistently on thick bladed knives and not on thin ones and vice-versa. This conformity in stamps makes me think that certain inspectors were responsible for knives created in one geographic region, or that they were assigned to certain manufacturers. All of the thick bladed P-3 (and P-2 as well) that I have seen had the broad arrow and one of these three stamps: “I”, “42”, or “B2.”  Shown below is a less common stamping, the broad-arrow with No. 21 stamp.

Obviously, given a choice, a thick blade is generally preferable to a thin one for reasons of strength. As noted elsewhere many of the thinner blades were known to be fragile and of poorer quality. This was especially true of post-war knives and those made in third world countries. At one time it was thought that only the thick blades were forged and the thin ones were ground from flat stock but other experts have stated that they were all forged. Of course proper heat treat may have been an issue with blade breakage as well because a thin blade, of the correct steel, properly heat-treated, can be quite tough. A good example of this are the excellent “Castle Knives” commissioned and sold by William Cassidy.

FR693:
The knife shown below is the FR693 knife with the broken blade. It is presently sheathed in a US GI Bayonet scabbard. One source says they are Wilkinson, another says BSA manufacture. Either way it is a top quality knife. It is the knife positioned far left in the array below.