10. ADVANCED TECHNIQUES
Depending upon the character of the target, it is a fairly straightforward
matter to plan a schedule of work to effectively disable
a site or facility. So far much of the detail in volumes I and
II has considered using tools to disable or dismantle equipment.
The use of other more extreme, complex or time consuming tactics
has not been considered.
Concrete can be put to very effective use. The only problem is
that it is difficult to transport, is a mess to mix and apply,
and it takes time to dry.
The cement used for brick laying is a mixture of sand and cement
powder. Concrete has small pebbles (gravel or 'aggregate') added
to increase its strength. The strength of the mixture depends
upon the amount of cement powder mixed into the sand or sand/gravel
- For general cement mix 4 parts sand to 1 part cement;
- For concrete mix 2 parts sand, to 1 part gravel, to 1 part
These gives you a very basic mixture. You could increase the amount
of cement powder to increase the strength, but this will progressively
'harden' the mixture so making it more brittle.
You can also buy special additives for cement which will increase
the speed at which it sets - these are usually based around PVA
and other similar adhesives. You could mix in a small pack of
wallpaper paste to get a similar effect.
With both concrete and cement, if you want to stop it being split
apart, you need to add some sort of reinforcement. Where space
is limited, you could try using wire mesh, or just random coils
of thick wire. If you are filling a space which you are sure there
is only one way it could be split with a chisel or drill, you
can bury steel plates or sections of angle iron in the cement/concrete.
You can also inject cement mix into things. If you want to do
this it is better to mix 1 part cement powder with 1 parts 'soft'
sand, and add a small amount of wallpaper paste/PVA. You then
need to use something like an icing piper to inject the mixture
into the space. Although you can carry this mixture mixed dry,
after adding water and mixing you will have to work fast as it
begins to set quickly.
Examples of where you can use concrete are...
- You can block up pipes using bungs (see Volume I) and then
fill the access hole with cement to prevent them being removed.
- You can create bollards or other obstructions by filling a
large steel drum with concrete. This tactic is even more effective
if you dig a hole, concrete a thick iron bar into the ground,
and thread the drum over the bar before filling it with concrete
- this makes it more difficult to push out the way.
- You can 'prefabricate' blocks or slabs of concrete to precisely
fit into holes or pipes using wooden or metal moulds.
- Pouring wet concrete into air intakes, exhausts, large electric
motors, gearboxes or any other mechanical systems which are enclosed,
assuming that there is the time for the concrete to dry, will
effectively block up the system, and it is cheaper than using
epoxy adhesives or potting compound.
The main thing to remember is that concrete is only effective
where it can dry properly. If there is no source of heat to drive
off the water, it will set very slowly. The speed at which the
concrete sets is proportional to the thickness of the concrete.
Concrete will form a hard skin within two or three hours of being
laid, but to properly set it takes much longer. Assume that, on
an average day, for each inch thickness of the concrete, it will
take four hours to dry. Adding PVA and other such compounds helps
the hardening process, but if you expect the concrete to take
a battering when it is discovered you will need to allow the full
four hours/inch thickness for it to dry.
An alternative to using a cement based concrete is to buy some
'bonding' or 'undercoat' plaster. Unlike cement, this has a much
more powerful crystallisation reaction so that it sets faster.
The main advantage of plaster is where you are filling watertight
enclosed spaces, as the crystallisation reaction will still take
place, and the heat produced by this reaction will help drive
off the water. The only problem is that plaster is very soft,
and so can be easily removed. This can be partly solved by using
reinforcing wire and metal plates.
10.3 Soldering/braising and welding
Often with metal objects it can be useful to have a more effective
method of gumming things up than superglue.
If you have two pieces of metal sheet, these can be firmly fixed
together using rivets. You drill a hole, insert the rivet and
then use a rivet crimp to seal it up. The problem with rivets
is that they are easily drilled out again - and you can only use
then on thin metal sheets.
Soldering methods (figure 39)
Soldering tools (figure 40)
With sold metal objects things get a little more difficult. If
the objects are small, or they are thin, then soldering or braising
is possible. First you clean the surfaces until they are shiny
and free from grease. Then you bring the surfaces together and
fuse them by melting a metal over them. 'Soft' soldering is used
for small objects, and basically involves using a soldering iron
to heat the parts, and then applying solder.
Where the metal parts are more substantial you may have to use
'hard solder'. You apply the flux to the parts. Then heat using
a large iron or blow torch. When the parts are hot and the flux
molten you apply the solder.
Soldering can be used to fuse metal parts up to 1cm thick, but
beyond this it is extremely difficult to get the metal hot enough
to take the solder. Also, solder joints are not incredibly strong
as the solder does not have the same strength at the metal. The
alternative is to use a gas or electric arc welder. This uses
very high temperatures to melt and fuse the iron/steel. This joint,
if properly made, has a strength near to that of the metal itself.
Arc welding equipment is difficult to use for sabotage work. It
is very heavy, because of the heavy copper coils inside, and there
is the problem of providing a power supply. If these problems
can be overcome, arc welders are fairly simple to use after a
little practice. Gas welding equipment is easier to carry, and
does not require a power supply, but it takes a little more skill
and practice to use. Oxygen-propane systems are relatively simple
to use to fuse metal. Oxygen-acetylene systems operate at higher
temperatures making work quicker, and the higher temperature also
enable you to cut metal more simply. Many local technical colleges
run evening classes on welding and metal work. I would suggest
that you attend one of these, or get a friend who knows to teach
you welding, before you attempt to use welding equipment.
The other option for welding/cutting metal is to use some sort
of 'thermite' compound, but this is difficult to obtain, and risky
to use. There are 'home-brew' alternatives using mixtures of solid
fuel and oxidising agents (see the following section).