GB2191709A - Fencing blades - Google Patents

Abstract

A fencing blade is made from 2 portions (1,2), which are joined together by butt welding, e.g. by laser or electron beam. Portion (2) extends up to the tip and is more highly stressed than portion (1), and is therefore made of higher grade steel than portion (1); e.g. portion (2) is made of managing steel and portion (1) of carbon steel. A collar (4), also of steel, can be secured using screw (5) to a depression (6) in portion (1), to provide an abutment (7) for a hand guard. <IMAGE>

Description

SPECIFICATION This invention relates to improvements in sword fencing blades This invention relates to improvements in blades for fencing swords and to methods of making such blades.

Conventionallythe blades of fencing swords have been made from carbon steels and have a rectangular cross section shape, tapering from the handle end of the blade to the point ofthe blade (see Figure 1). The tang end ofthe blade consists of a 6mm diameter round section normallythreaded 6mm, this is followed by a short square section of approximately 6.25mm2. This 6.25mm square section is common to most blades and is used to prevent the handles which are passed over it from rotating. Afterthetang of the blade is an area termed the 'forte'. This is approximately 1 00mm2 in cross sectional area and over a short distance of 30/1 OOmm tapers down to a cross sectional area of approximately36mm2.Over the restofthe length of the bladethetaper is much more gradual and, at the tip, the cross sectional area is down to approximately 6/10mm2. The purpose of the 'forte' region is twofold. Nearest the tang it produces an area to which the guard and handle can be butted up against, the assembly can thus be tightened up by means of a nut threaded onto the threaded section of the tang. The forte also affects the balance and feel of the assembled weapon, the size and shape ofthis region can change the centre of gravity of the assembled weapon and its total weight. Experts at fencing have always felt that these two considerations were very important.Up to the present time there was no way of altering the balance and feel of a blade and the fencers had been left with the choice of three or four fixed blade designs, weights and shapes. Because the maximum cross sectional size ofthe forte is approximately 100mm2traditionally blades have been forged from short billets of starting cross section of 1 00mm2.

This, in practice, represents a short billet of either lOmm x 10mm2 or 11 .2mm diameter. (These dimensions given are obviously only approximate).

Therefore, during manufacture the reduction ratio from forteto tip is approximately 10:1. This has always required either multiple passes of an automaticforging machine or multiple reheating and forging in a manually operated forge.

Due to the problems of the conventional steel blades breaking, causing injury and death, recent regulations made by the ruling body of fencing have called forthe use of much more expensive steels, which cost up to 30 times more. These expensive steels can require difficult forging techniques and complexheattreatments. Howeverthese newsteels have a much longer life in use and tend to break in a safer manner.

According to the present invention, there is provided a blade for a fencing sword which is made from the expensive high performance material over the length of the blade which is stressed the most.

The restofthe blade is made from low cost carbon steel or similar material. In some embodiments of this invention there is provided a means offorming a forte region of variable weight such that the expert fencer can, for the firsttime, adjust the weight and hence the feel of his blade to suit his own personal requirements. This weight can be supplied in different sizes and materials and in the event of the blade breaking, can be removed and used again. In training a fencer might well practise with a heavy weighttostrengthen his musclesandthen changeto a lighter weight in competition. The blade so made is easy to manufacture and will be much less likelyto contain flaws and forging or rolling imperfections.

The main highly stressed part of the sword blade is made from very expensive steel which is obtained from the manufacturers in the form of approximately 6.25 x 6.25mm2 bar. The tang is made by welding a length of approximately 6.25 x 6.25mm2 bar of conventional cheap steel to one end ofthe expensive steel bar. The length of this tang part is made such that the weld position will end up in the middle ofthe forte region.

The rod now formed consists, at one end, of a cheap steel and, at the other end, the expensive steel.

By holding this rod at the expensive end, the tang can beforged down to 6mm round and to the required length. This rod can now be held bythetang which has been formed and can now be forged down to the normal conventional shape, with the exception that over the forte region the blade remains only approximately 6.25mm2. The forte region is built up by means of a shaped collarwith a square hole through it of the same size as the starting rod. This collar can be made from any metal such as steel, aluminium or even from a plastic. The collar is positioned in the correct place and can be secured by any means offixing, i.e. glueing, welding, bolting, rivetting, clamping.Because the starting size of the bar is nowso muchsmalleranautomaticforging machine can forge down the blade in one pass. Due to the minimum amountofforging required to produce such a blade, the blade so formed will be more fault free than conventional blades. In particular, trials of forging down with some of the expensive steel from standard sized billets (e.g.

11 .25mm diameter) have shown that by the beginning of the last pass the steel has cooled down so much that faults are introduced into the blade surface during the last forging pass.

In orderthatthe invention may be readily understood an embodiment thereof will now be described in more detail by way of example, with reference to the accompanying informal drawings.

Figure No. 2 shows a side view of a fencing sword having a blade which embodies the invention. Figure No.3 shows the detachable collar. Referring to Figure No. 2, fencing sword comprising a tang 1 made from EN 19 carbon steel threaded forthefirst 140mm with a 6mm thread and a section 6.25mm2 for a length of approximately 40mm. The remainder of the blade is made from maraging steel 2. The two sections are joined by butt welding at the point 3. By placing the weld at point 3, the joint is at the point of minimum bending stress while the blade is being used and the weld is hidden by the collar, so that very littleweldfinishing needs to be done. Covering the weld is a collar made from steel 4.Referring to Figure No. 3,we see the collar is made with a square hole through the centre, such thatthe blade can be passed through the collar and positioned as shown in Figure 2. The collar is attached to the blade and prevented from moving by a small set screw 5, which locates in a small depression formed by drilling or some other means into the blade surface 6. The depression is so positioned that it remains in the EN19 section ofthe blade. Thus, when the weapon is assembled and tightened up with 6mm nut no stress is put on the weld between the maraging and EN19 steel section.

The balance and the weight of the blade can be altered by changing the size or density of the collar.

When a weapon is assembled the guard will butt up againsttheface 7 as shown in Figure 2.

Maraging steel is heat treated by ageing for4 hours at4800. Blades made entirely from maraging steel must subsequently be softened at the tang, with the tang made from EN1 9 this is not necessary and no furthertreatment ofthe tang end is required.

The welding shown at3 is such that the blank prior to forging is one continuous rod such that the blank can be easily handled during the forming ofthetang and the rest of the blade.

As blades normally break in the top half, it would also be possible to make a similar blade as outlined above but with the weld much further along the blade. For a blade manufactured in this manner, it is envisaged that a more accurate form of welding might be necessary such as laser welding or electron beam welding.

For blades of the lowest cost and the lowest weight, the metal collar can be replaced byashort pin. See Figure 4. This pin is of approximately length 15mum which passes through a hole previously drilled perpendiculartothe main axis and passing through the blade neartheforte region. The pin protrudes from both sides of the blade such that a guard can be made to butt up against it.

Other possibilities exist such as a simple washer welded in the correct position. See Figure 5. It would also be possible to make a controlled upset such that a shoulder is formed atthe desired position. This upsetting could be formed before or afterthe blade has been forged. See Figure 6.

Alternative methods exist for making a protrustion such that the guard can butt up to a stop. Distortion ofthe blade such as pressing to form a bulge and plastic moulding a permanent collar to the blade.

Although the collaras shown in Figure 3 is a separate piece itwould be possible to make the collar an integral part of the guard. See Figure 7. This might well give some economy in manufacture, in particularfora iowcostschool bladethe guard and handle and fixing collar could be plastic moulded in one piece.

Because, with the system outlined, there are advantages in the ease of manufacture and the fact that less faults will be introduced into the surface of the steel during forming, and also the advantages of being able to adjust the weight of the blade, it is envisaged that blades could be made out of expensive high performance steel such as maraging steel or normal conventional steels throughout. The method of construction is similar to that that has been outlined but there is obviously no weld in the forte region and the blade is made from one length of approx. 6.25mm square bar.

In most of the embodiments of the invention mentioned the starting size has been assumed to be approximately 6.25mm2 square. This size is chosen due to the fact that the guards and handles are made to fit a normal sword blade with a tang of size not greater than 6.3mm square near the forte and 6.00mm round for the rest of the tang (see Figure 1).

Also blades made from steel which produce a size much smaller than 6.25mm2 square or39.mm2 cross sectional area just after the forte region are felt by experts in fencing to be too flexible at this point The following describes another embodiment of the invention referring to Figure 8 the tang 1 is made from 6mm diameter studding, which is butt welded at3to 6mm diametermaraging steel 2. The6.25mm square section of the tang is formed during the manufacture ofthe collar, see 9. The collar is fixed and positioned as already described using a small set screw. The normal rectangular cross section shape of the blade is introduced into the bladejust after the collar. For beginners the blade so produced would be adequate, howeverfor reasons of lack of stiffness at the forte region a blade madeforexperts would need to be made with the starting maraging material being larger in diameter or square. The two different sized bars being butt welded in the manner and position already outlined.

There are, in fact, three different types of fencing blade. The foil blade is shown in drawing 2. The other two blades have fluted ortriangularcross sections.

However, they all have a forte region and taperto a small size. Blades as outlined can also therefore be manufacturedforthe other two types of blades which are called epees and sabres, the collar being adjusted in size and shape to fit the desired cross sectional shape.

Claims (25)

1. A method of producing a fencing blade, comprising making a most stressed portion ofthe blade extending from a tip ofthe blade from one grade of steel and the remaining portion of the blade from another lower grade of steel joined to the steel of the one grade.

2. A method according to claim 1, comprising forming a starting billet by joining together bars of the two grades of steel and processing the resulting starting billet to form the two portions of the blade from the respective parts of the starting billet.

3. A method according to claim 2, in which at least a portion of the starting billet has a square cross-section.

4. A method according to claim 3, in which the square cross-section is 6.25 mm square.

5. A method according to any one of claims 2to 4, in which at least a portion of the starting billet has a round cross-section.

6. A method according to claim 5, in which the round cross-section has a 6 mm diameter.

7. A method according to any preceding claim, in which the one grade of steel is maraging steel and the other grade of steel is carbon steel.

8. A method according to any preceding claim, comprising processing the billettoform a blade having a finished shape which presents no abutment in a forte portion ofthe blade forthe mounting of a guard or handle, and then separately processing the blade to provide an abutment.

9. A method of producing a fencing blade, comprising processing a starting billettoform a blade having a finished shape which presents no abutment in a forte portion ofthe blade forthe mounting of a guard or handle, and then separately processing the blade to provide an abutment.

10. A method according to claim 8 or 9, in which the separate processing comprises attaching an abutment memberto the forte portion ofthe blade.

11. A method according to claim 8 or 9, in which the separate processing comprises processing the material ofthe blade to form an integral abutment.

12. A method of producing a fencing blade substantially as herein before described with reference to the accompanying drawings.

13. Afencing blade in which a most stressed portion ofthe blade extending from a tip of the blade ismadefrom onegrade of steel and the remaining portion ofthe blade is made from another lower grade of steel joined to the steel of the one grade.

14. Afencing blade according to claim 13, in which the two grades of steel are joined in a forte portion of the blade

15. Afencing blade according to claim 13 or 14, in which the one grade of steel is maraging steel and the other grade of steel is carbon steel.

16. Afencing blade according to any oneof claims 13to 15, in which an abutment member is attached to the forte portion of the blade to provide forthe mounting of a guard or handle.

17. Afencing blade having a forte portion of substantially uniform cross-section and an abutment member attached to the forte portion to provide for the mounting of a guard or handle.

18. Afencing blade according to claim 16 or 17, in which the abutment member is a collar received on the forte portion of the blade.

19. Afencing biade according to claim 18, in which the abutment collar has an extension of round internal cross-section for receiving a tang portion of the blade having a round cross-section,the extension having a square external cross-section.

20. Afencing blade according to claim 18, in which the abutment collar is formed integrally with the guard or handle.

21. Afencing blade according to claim 16or 17, in which the abutment member is a pin received in a transverse aperture formed in the forte portion ofthe blade.

22. Afencing blade according to claim 16 or 17, in which the abutment member is a washer received on the forte portion of the blade.

23. Afencing blade substantially as hereinbefore described with reference to the accompanying drawings.

24. Afencing sword having a blade according to any one of claims.

25. Any novel feature or combination offeatures described herein.