This article was first published in 2005.
Until recently, whenever I’ve wanted a solvent to clean off grease – or to
just clean a part – I’ve used petrol, meths or kerosene. But then I bought a
container of ‘grease and wax remover’... and now I use it on nearly every heavy
duty cleaning job! From cleaning off the oil on a set of new brake discs, to
wiping over metal parts before painting with a spraycan, to removing greasy
smears from the inside of door jambs or cleaning surfaces before applying
double-sided tape – it’s worked superbly. It’s available from shops selling
Here’s something that’s very seldom thought of – but it makes lots of sense.
When installing components under the dashboard (anything from an alarm module to
a new ECU), it pays to think of what would happen in a crash. I was recently
installing a folded sheet aluminium bracket to hold an electronic module in
place, when I realised that the original design of the bracket would have a
thin, sharp edge directly facing the front seat passenger. Of course, being
buried inside the dash it was hidden from view, but if the dash had been pushed
towards the passenger in a crash, that knife-like bracket was in an ideal
position to slice them. In this case the simple answer was to fold-up a wide lip
on that side of the panel.
If you’re organised, you can save yourself a lot of time and frustration. One
easy part of that organisation is to keep all fasteners that you come across. So
if you’re bought a car part from a wrecker and it has bolts, screws or nuts that
you don’t need for the project, don’t throw them away but instead remove them
and place them in small containers. The high quality bolts that you salvage in
this way are almost impossible to readily buy (eg the ones with captive washers)
and if you’re working on just the one make of car, you’ll find that many of
these salvaged fasteners are a direct factory fit in other car applications.
That is, the bolts will have the same threads, same typical lengths, same socket
sizes, and so on.
We’ve covered it before in detail at Zero Cost Trickle Charger, but it’s worth repeating here. If you have a need for a
small trickle charger ("trickle" meaning that it’s the sort of charger you leave
attached for a few days in order to bring up battery voltage), you can make one
for just a few dollars. All you need is a nominally 13-15V plugpack (wall-wart
in the US), a resistor and a few alligator clips. That’s all! With many people
throwing away plugpacks, it’s a no-brainer to source a suitable plugpack for
nearly nothing (secondhand stores, the tip, kerbside collections, etc) and then
the rest is simply so easy. Since the original article was written, I’ve now
built three of these chargers – right now, one is charging a spare 12V car
battery, while another is charging my electric bike batteries.
Pressure gauges use technology that hasn’t changed in 50 years. A curved tube
inside the gauge (called a Bourdan tube) straightens under the influence of
pressure. The tube is connected by a gear mechanism to a pointer. This lack of
technological change makes an old pressure gauge just as useful as a brand-newie
– so long as the old one is in working condition, of course. Recently I sourced
a boxful of old gauges (they were bought at a household goods auction – cost of
the box, AUD$12) and in it were two gauges useful for automotive applications.
One is a compression gauge and the other a calibrated and marked vacuum gauge –
that’s the one shown here. Check our article on
Using a Vacuum Gauge for Engine Diagnostics
and remember, always look with close interest if you
see secondhand gauges cheaply on sale.
Most insulated electrical wire has a low temperature rating – at anything
over about 80 degrees C, the insulation covering starts to soften and melt. High
temperature rated cable is available – but only from specialist suppliers and at
a tall price. But if you have a need for some high temperature insulated wire
(eg when the wiring has to pass close to the exhaust), short lengths can be
easily got for nothing from junked stoves and hotplates. The wiring is rated up
to 150 degrees C, and uses silicone insulation or high temperature sleeving. The
current rating is also quite high – this is good quality wire! In many cases,
spade terminals will already be crimped to the cables.
Every now and again you’ll have a need for hefty electrical eye terminals –
the sort that have enough current capability to work with battery cables. It
might be because you’ve moved the battery to the boot, it might be because you
need a new earthing strap, or you might just be wiring-in an ammeter or high
power amplifier. In all cases, if you’re stuck for terminals, it’s easy to make
your own. All that you need do is select a piece of copper tube that has the
right internal diameter to match your cable. Cut off a short length of the tube
and then use a vice or a hammer to crush one end flat. Round off the sharp edges
of the crushed end with a file and drill a hole through that end. Hey presto,
one heavy duty lug terminal!
Whenever you’re shopping, keep an eye out for goods that can be turned to
alternative, automotive uses. This coat hanger is available in a bunch of five
for about five bucks. So, you don’t want any coat hangers? Well, think again.
The hanger is constructed from beautifully bent 8mm thin-wall stainless steel
tube! Cut the coat hanger up with a hacksaw and you have five bends (ranging
from 180 to 90 to 30 degrees) and several straight lengths of stainless steel
tube. They’re just the things for squeezing turbo wastegate or vacuum line
plumbing into tight underbonnet spaces – the bends are much tighter than you’d
readily achieve with hose alone.
While it’s very common for modifiers to use sheet steel and aluminium, you
rarely see them using plastic. That’s a pity because plastic sheet is easy to
cut and bend (to do the latter, heat it first) and is often better in certain
applications than metals. ABS is a tough and resilient plastic while acrylic is
available in a range of colours, including clear sheet. The best approach is to
find a company that uses the plastics to manufacture goods and then approach
them in search of off-cuts. Some recycling organisations also have plastic
off-cuts available. The cover for the circuit breaker mounted on the outside of
the battery box was made from an acrylic off-cut.
If you look around at any place where junked consumer and automotive goods
can be found, you’re sure to see some printed circuit boards with excellent
components still intact. For example, the other day I came across a Bosch ABS
controller that was being chucked. On it was a heap of components. Although most
were not usable for someone with my level of electronics knowledge, there were
also four high quality 12V miniature relays. Relays that would be perfect for
lots of uses! However, if you’ve ever tried to unsolder multi-pin components,
you’ll know how hard it is to do this without stuffing the component. But
there’s a very easy answer – aim a heatgun at the solder side of the board and
after a few moments, the component will almost drop off! At the most, all that
will be needed is a slight wriggling with a pair of pliers. One of the relays
salvaged from the ABS controller can be seen here, being made use of in a
completely different application.