Armoury Tip 1 – Resolving white light problems

Summary (more detail below)

  • Keep your weapon in regular use to reduce tarnish (corrosion) building up on contacts in the point and bodywire socket!
  • Twiddle the point and wiggle the bayonet plug to shine up tarnished contacts
  • Try tightening the barrel especially if faults are intermittent. Warning! This can break the wire if you are not careful/unlucky.
  • Grub screws are a consumable in Leon Paul barrels. Replace them to reduce ongoing white light faults.
  • Swop weapons with your opponent to eliminate a weapon fault before investigating bodywire faults. OR, the quicker way
  • Short the bayonet plug point with the return side on the guard of the foil. If the fault disappears then it is the weapon. See Armoury Tip 3 – Problems solving
  • If the weapon exchange or shorting test still shows a fault on your side, plug your bodywire into the opponent’s fencer end socket. If the fault changes side it is your bodywire OR
  • Ease out the bodywire plug from the fencer end socket but leaving a connection, so that you can short the centre and furthest pin. eg with a coin or screwdriver. If the white light goes out then the problem is the bodywire.
  • If these tests check ok then do the same at the ground wire connection into the spool. If the white light goes out then it is the spool.
  • If the fault remains then the same check on the plugs partly removed from the box. If the white lights go out it is the ground wire.
  • If you have no shorting device you can also remove the ground wire from the spool and touch all three bodywire contacts to the same three bodywire contacts. ie pin to pin. If the fault disappears, replace the spool. If fault remains, replace ground wire. (The final proof is to plug your bodywire directly into the electric box!)

DO NOT beat your blade on the floor to ‘remove dirt’ from the point. It can cause damage to an otherwise much abused point and barrel and is a total waste of time. 

In more detail.

Probably the most common (and most irritating) faults with electric fencing are those that cause incorrect ‘off target’ white lights. This is because there is a continuous circuit in a foil, until a hit is made, so any fault in the circuit will register as ‘off target’. (Epee does not have this problem!) In addition regulations require the electrical resistance of the bodywire/weapon circuit to be less than 2Ω(Ohms) which is quite hard to achieve! A resistance of 12Ω is enough to cause the electric box to complain.

There are over 30 dry (unsoldered) joints between the tip of a foil and the electric box on a Leon Paul kitted box, a little less with Allstar/Uhlmann which has more soldered contacts, and any of these can cause white lights but the majority of faults that arise are on the weapon especially those marked with * on the list at the end of this article followed by broken body wires.

Here we will concentrate on what you can do on the piste.

The most common faults in order of occurrence are:
  1. Inside the point barrel
  2. Bodywire breaks
  3. The guard socket

White lights often occur, I find, when a weapon has not been used for a while. Tarnish  (corrosion) builds up on the contact surfaces in the barrel and in the bayonet socket. Take this as a sign you should be fencing more often!

  1. The barrel

Some fencers try to resolve point problems by beating the blade on the floor “to remove dirt from the point”. This should be a criminal offence! It can lead to breaking the wire completely where it enters the brass disc inside the barrel. Especially if the problem is actually a loose barrel. (It should also never be done on a mesh metal piste which will earn you a yellow card).

These are first best resolved by twiddling the point. This shines up the contacts between spring and brass base and between point and grub screws and reduces resistance. The grub screws are made of mild steel, even in the new titanium points, so are very soft and will rust!

General usage (and, especially, ‘twiddling’!) wears flat spots on the side of the grub screws and this leads to faults. Grub screws should be considered a consumable and all fencers should be able to replace these as a first step to resolve ongoing white light issues. (I find it advisable to replace grub screws before a competition or at the same time I renew the tape).

Sometimes the barrel can work loose and intermittent white lights occurring when blades come in contact are a symptom of this. Tightening the barrel with the fingers may give a temporary solution but really needs to be done with a spanner and with the blade in a vice. Care must be taken when turning the barrel so as not to break the wire/base contact connection. The application of some thread lock will also help (see Armoury Tip 5). An Armourer can assist with this.

2. The bayonet socket

This is a real weak point and there is a lot to be said for the continental 2 pin connector although even those have a downside,  Again the main problem is tarnishing of the brass contact and also of the mild steel spring connecting the brass disc to the contact in the bottom of the socket (to which the blade wire is attached by a screw terminal).

A good wiggle of the plug in the socket will often shine up the brass disc whilst you are on the piste but the spring and contact underneath are not really agitated by this. I have seen some fencers spit into the socket. The saliva presumably acting either as a solvent or just providing a liquid conductor!  However, the only long term solution is to remove the brass disc by tilting it with a screwdriver (or better some narrow nosed pliers) and agitating the spring against the contact in the base. (A quick squirt of an electrical contact  cleaner works wonders. But not on the piste!)

Also check that the screw connector for the blade wire is tight.

Very occasionally a blade wire will break. The most vulnerable place is behind the guard pad where it passes through the guard and also at the attachment to the bayonet socket.

3. A loose handle. The electrical circuit depends heavily on good contact between blade and guard and between guard and socket bracket. A loose handle will raise resistance levels. Make sure the handle is tight ensuring the point wire is not trapped by the handle or under the socket bracket.

4. Body wire breaks

Bodywire breaks are tricky to determine as, in their early days, the break may only cause an intermittent fault. They most frequently occur where the wire exits the bayonet plug as this is next to the fingers and is constantly moved while fencing and during connection and disconnection. It is also prone to sweat rot. However, wiggling (the usual technical approach) also disturbs the rather fragile bayonet socket connection itself so can be inconclusive.

Breaks also occur where the wires exit the fencer-end plug (behind you!). These are caused from pulling the wire to remove the plug from the fencer-end socket. Don’t do that! Other breaks occur over time where bodywires are pulled from behind to reduce excess cable in the hand area. eg after a disarm. Always hold the arm pointed up vertically before pulling the wire through the sleeve. The body wire can also be stretched in any number of other ways. Take care with this and it will last a long time.

The quickest way to prove a body wire fault is to use a second bodywire fully connected, initially outside the jacket, just to get confirmation, before going through a full body wire change over, just in case it is a fault elsewhere in the spool or ground wires. Or change over with the other fencer and see if the fault moves with you.

Faults at competitions are, at best, irritating to others and can delay proceedings while investigations take place and, at worst, can lose you a point or a fight. Always have a spare weapon and bodywire with you. If you cant stretch to that just have a word with the club armourer before a comp and we may be able to lend you these items for a small deposit. Test them first!

If your weapon is still causing problems after these actions have a word with an Armourer.

Just for interest here is a list of all twelve dry joints on a foil starting from the socket, heading to the point and back down the blade returning to the socket.

  • *Bayonet plug central connector (the screw tip) with brass contact disc in the socket
  • Brass contact disk with socket spring
  • Socket spring with base contact
  • Base contact with blade wire (screw) from here the wire travels up the blade to..
  • *Blade wire with brass base contact inside the barrel
  • *Brass base contact with point spring
  • Spring contact with point (here contact is also made with opponents lamé)
  • *Point with barrel via 2 grub screws (now we are on the ‘earth’ side of the circuit)
  • *Barrel with blade
  • Blade with guard (never thought I would get  a problem here until recently! Use a file or coarse emery paper)
  • Guard with bayonet socket bracket (can need a spot of medium emery paper to remove tarnish)
  • Socket bracket with bayonet plug (T-piece)

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