Bob
Fenton's car was recently the first Locust to pass the SVA, here
is Bob's build report.

A
friend of mine bought a set of Locust plans back in 1986, but like
so many sets of plans they languished at the bottom of a drawer
somewhere and never got built. One day we were chatting about kit-cars
in general. He mentioned that he had a set of TJ plans for a wooden
- bodied car.
Being
a boatbuilder by trade, I was intrigued with the idea that the 'offcuts'
from the boats I build would go a long way to making a body. However,
when it came to it the sizes and thicknesses did not work out. I
needed to buy some fresh material.
I
had been sold on the idea of using plywood, but I learnt that MDF
would be suitable if was of the exterior variety. Having never used
the dreaded MDF, I thought I would give it a go - just for a change.
The
'so called' 'Manual' that came with the plans was the original TJ
production. I contacted WRV to see if (a) the plans would
still 'work' and (b) if a more informative manual was available.
The reply was 'Yes' in both cases. The manual still leaves
quite a large number of things unsaid. I suppose this is half the
fun of doing it this way, as you really have to work the details
yourself.
I
was concerned to read that the use of PVA glue for construction
and waterproofing was recommended. I reasoned that Marine adhesives
and coatings would make a better job. I used what I make my boats
with. This is known as W.E.S.T. This stands for Wood Epoxy
Saturation Technique.
The West System
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Resin Part No. 105
Hardener (for gluing) Part No. 205
Hardener (for coating) Part No. 207
Filler Powder Part No. 403
(for gluing and filleting)
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Supplier:-
Robbins Timber,
Brookgate,
Ashton Vale Trading Estate,
Bristol BS3 2UN
0117 963 3136 Tel.
01779637927 Fax.
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Ask for the West System
Technical and Product Catalogue
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WEST
is a liquid epoxy, like thin Araldite. When it is mixed with the
appropriate hardener it can be used to glue things and coat them
to make a 100% waterproof job. When glueing, a powder is used to
thicken the mix so that it does not get squeezed out of the joints
or run away.
The
beauty is that it will act as a filler when the fit is not as good
as we might hope. It is a very forgiving stuff, but it doesn't like
temperatures below 10 degrees OR it won't set.
I
had planned to spray paint my Locust. The WEST epoxy coating can
be flatted down to make a good surface for spraying. Standard cellulose
is fine over a unviersal flexible primer. The idea of using alloy
angle on the corner joints did not appeal at all. When I build my
boats, I use the epoxy, suitably thickened, to put a 'fillet' in
the corner of every joint. I have done my own tests on the strength
of this sort of joint and have absolute faith in the method. (I
have been out in some very unpleasant seas in my own boats and the
hull joints have never been a worry).

The
epoxy fillet makes a neat and easy to clean interior and takes away
that 'Meccano kit' look when angle is used. I am also sure that
the epoxy method is just as strong. It is also MUCH QUICKER.
There
is a down side. Cost. However, bearing in mind that it has so many
advantages the percentage cost of the Epoxy compared to the total
cost of the car is not so bad. WEST is so good that you could take
a large brown paper bag and soak it in the stuff; when set it would
make a perfectly adequate boat; or if you bolted wheels on it -
a car!
Tools.
If
you don't have a cordless drill / screwdriver - get one! I use several
that I have collected over the years. Nevertheless, even with one,
the time and effort you will save is tremendous. Get the special
bits that drill a pilot hole, clearance hole and countersink all
in one go. Then use Posidrive screws and put them in using the torque
control on the drill so as not to over - tighten. If you are screwing
into the edge of the MDF, don't put a screw any closer than 40mm
from the 'end' of the material or it will split. (Not the end of
the world as WEST will glue it as good, or better, than new). A
word of warning. If a screw is put into a 'Wested' joint you will
never get it out again once the glue has set, unless you apply some
heat down the shaft of an old Phillips screwdriver into the head
of the screw.
Paper
patterns.
I
didn't glue the patterns down to the material, but rather pricked
through the vital points and then checked them with a few measurements.
I reasoned that the patterns would come in handy when interior panels
needed to be made. An advantage of MDF is that, as it has no 'grain',
you can place the patterns in any direction on the board and thus
be very economical
The
cutting out was done with a jigsaw, although I am lucky enough to
have a large band - saw which can cut the angles required on some
pieces.
There
has been some adverse press about the carcinogenic properties of
MDF dust (from the Phenol in the bonding agent) so I think it is
wise to take some sensible precautions when using this stuff.
(The
same goes for WEST; wear a face mask when sanding and gloves when
glueing. Some people are allergic to these chemicals rather like
the problems with GRP work. Some are just allergic to work).
Building
the Body.
If
you follow the manual, you won't go far wrong. I don't have much
to add on this score except that the way I made the corners between
the back panel and the flanks differed from that suggested.
I
use a kind of very flexible plywood in my work. The stuff is 6mm
thick and will take bending to the radius on the back corners of
a Locust with ease. To allow the plywood to come flush with the
outer surfaces it is necessary to rout a step on the back panel
and the flanks. It is very easy to do and the Epoxy will bond the
'bendy ply' to the panels and make a strong job.

When
boatbuilding, I often use a gizmo called a 'fairing board'. This
is a strip of 6mm plywood about 800mm long (or longer) and the same
width as the roll abrasives. A handle is glued and screwed to each
end in such a way that a strip of 40 grit abrasive is stretched
along the bottom of the board, and trapped under the handles. Using
this giant sanding block you can 'fair-in' the top and bottom so
that the compound angles all blend in correctly before you put the
corner filler in. The fairing tool is also handy to fair up the
filler that may have been used at the bend in the side flanks /
valences. (Incidentally, I did this joint with dowels and a reinforcing
of several layers of 200gm woven glass cloth, all epoxied on, just
like GRP work)

I
had seen several Locusts where the nose -cone overlapped the side
valences. It did not look too neat, so I routed a step in the valence
the same depth as the thickness of the GRP. Using DZUS fastenings
with the anchor plates epoxied into the valence it made a neat job.
The level of the surface of the valence and the nose will now be
the same.

When
the dash panel, nose- cone and the scuttle were all in place it
was clear that something was not right. Boatbuilders do a lot of
work 'by eye' to see if the complex compound curves of a boat are
'fair'. By using a 'fairing batten' (a long thin piece of wood about
10mm x 25mm section) placed along the line that the bonnet would
take to join scuttle ,dash panel and nose-cone in one 'fair' sweep,
I could see that all was not well. Using the fairing
board it is possible to alter the radii and angles of the scuttle
and dash panel so that it comes right 'by eye'.
If
you take this path, you will find that the radii of the top corners
of the nose-cone will differ from the scuttle and dash panel. When
you come to make the bonnet the bend in the bonnet will not be a
simple curve, but will be a changing radius along its length. To
produce such a curve it is necessary to 'wheel' the bonnet so the
changing radii will match up with the scuttle and nose - cone at
either end.
I'm
fairly sure that some compromises have been made in the design of
the plans in this area to keep things simple. However, I believe
that to get the line of the bonnet / scuttle / nose-cone right it
is necessary to step back and look carefully at the line these should
take. This would also have implications for your windscreen frame
fit. If you use MDF it is possible to put a neat radius on the top
edges of the body to replicate the shape of the original Lotus.
Using a bearing guided rounding over cutter in a router you can
put a super rounded shape to all the necessary edges and get
away from the idea of bending 'D' alloy round the edges. This,
unless it is done with great care, looks a mess. Add a couple of
coats of epoxy and flat off -you are ready: to spray.
I
also made the following modifications as I went along to make access
easier and to bring the handbrake to a more ergonomic position.:-
The
top face of the tunnel was cut down to make a step where the handbrake
fell naturally to hand, and a welded - up ladder - frame arrangement
fitted in the gap between the two sides of the tunnel. This provided
a mounting for the gear - change (sawn off the gearbox and repositioned)
and the handbrake with its necessary cable anchorage. The whole
lot is held by countersunk machine screws through the tunnel sides
which are tapped into the frame. An access hole for the reverse
light switch is a good idea while in this area.

A
large access hole was cut in the gearbox side of the driver's footwell.
This gave better access to the pedals and the end of the well. But
as I skinned the gearbox side of the opening with the alloy sheet,
it gave 3/4" more foot room in an area where every fraction
of an inch matters.
I
cut a similar hole right over where the petrol tank and sender unit
would come and followed the advice about making extra clearance
in the prop-shaft area next to the driver's seat as 'per the manual'.
It
might be of interest, at this point, to explain about my workshop
where I build small sailing boats. The building has a fair sized
ground-floor workshop where the boatbuilding goes on. It has two
rooms upstairs, one of which is set aside for 'clean' work like
varnishing spars etc. The front room became the home to the Locust
build. in a space only a little longer than the chassis and about
8 feet wide. Access is through two doors of normal house dimensions.
However, some friends and I got the chassis upstairs at an early
stage, while at the same time bringing the mechanical side along.
I could not fit the engine as I was worried about the weight on
the floor of an ancient wooden building!
I
knew that one day the whole lot would have to come down again. However,
it enabled me to carry on working on the boats and still do some
'overtime' on the Locust. The temptation to work on the car was
too much sometimes and I'm sure work suffered as a result. Later
a quiet time in the boat building business enabled me to bring the
pieces down again and reassemble them in the larger workshop - what
luxury! By this time I had the rolling chassis sorted and enough
done to move it to a rented garage not too far away.
The
rolling chassis.
Much
of this was standard stuff - Ford GT X-flow with Escort sport box
and MKII axle. I did use the WRV front wishbone assembly and this
caused much messing about. I reckon that to avoid bump-steer the
plane of the steering rack and the ball joints on the track-rod
ends should be the same ie horizontal at normal laden weight. When
the wishbones were assembled it was clear that the coil - over top
mounting would need raising to, in effect, lower the suspension
and give a horizontal aspect to rack, steering arms and wishbones.
They all ought to rotate about a 'common centre', which I feel is
impossible in practice. But a close approximation is needed to avoid
bump steering.
I
chopped away most of the top mounting and made extension plates
which would give me a choice of locations for the top bolt. Eventually
it all came right. The mounting for the forward wishbone mount,
which has to be welded on to the chassis, is a flimsy affair. I
wish the gauge of the metal could have been a bit greater to inspire
more confidence, but I am sure there is enough strength there -
just. When welding these on I was concerned that all the centres
for the inner pivot bolts would be in line. I did this by putting
a steel rod through the existing holes and then aligning the extension
brackets on that. I'm sure it wouldn't do if these mountings were
out of line. It is worth taking a little care.

Demands
of the SVA test suggest it would be an excellent idea to weld captive
nuts on the chassis at an early stage so that the seat - belt mountings
comply. 7/16" UNF is the size.
At
the rear end I discovered that the ride height was too high and
I wanted to lower it to reduce the gap between the wheels and the
arches. After much thought I took the body off and cut away all
the original top mounting. I replaced it with a fabricated welded
- on turret which goes right through the boot floor. In this way,
I had about 2" to play with in terms of adjustable ride height.
In my opinion it makes the car look better. Life is never simple.
I discovered that the rear suspension geometry allows the 'nose'
of the diff to droop the higher the axle is raised relative to the
chassis (which is what happens if you lower the car). To counter
this, I needed adjustable top links (trailing arms), so I chopped
them in two and added a thread to one end and a captive nut to the
other. All were carefully welded and with lock-nuts the scheme did
what I had hoped - the diff can be brought level again.
Wiring
and lights.
Just
because a Locust can be cheaply built, it does not follow that it
needs to be badly built. One area where I think it is worth spending
some money is on a custom made loom. A friend with a similar vehicle
used a 'butchered' Escort loom without unwrapping the whole thing
to remove redundant cables. The result was that the car caught fire.
Several
firms advertise looms -so shop around - or take the time and trouble
to study cable current capacities and do the job by starting with
fresh cable - or unwrap and get rid of potential hazards. A neat
loom, well clipped back, does wonders for the perceived impression
of the vehicle especially now that the SVA test is upon us.
If
you think ahead, connectors can be put in at the front end so that
headlights, indicators etc can be removed easily. The SVA testers
are no longer looking for 'E' markings but the height and position
of all lights needs to comply with the 'regs'. 'Kit Car' produces
an excellent guide to the SVA and I found all the info in there.
The car passed first time, so it has proved to be a useful guide
at a fraction of the cost of the Official Manual.
Vehicle Wiring Products from Ilkeston offer an excellent mail -
order service for electrical gear and I notice they now do lights;
failing that, Europa can supply almost everything in that line.
Throughout, I used the cheaper and less bulky uninsulated spade
connectors with heat shrink sleeving providing a neat insulation
and reinforcing to the cable / connector joint. 'Ripaults' type
multi-way in line connectors were used whenever a component needed
to be disconnected at a future date.
Pedal Box.
My
wife bought me a book about the Lotus 7 as a Christmas present so
I spent the day designing a pedal box which was based on a photograph
(better than watching bloody television!). I never was happy with
the idea of using the Ford offering and the Triumph stuff was not
too easy to get hold of at a sensible price. I used Escort pedals
but re-positioned the pivot points by chopping them into slices
and rearranging the bits.

The
standard item has the pedal pivot at the top and the push rod pivot
below: what we need is the reverse of this to enable the push rod
for the master cylinder to act above the pedal pivot. If you use
the original pivot bushes and pins you can end up with an item which
should be reliable and offer the chance to re-bush things if they
wear.

Steering.
The
normal Escort column and rack were pressed into service. A friend
of mine told me to be careful when extending the lower column with
a tube as the welding is critical as well as the method. Some of
the material will be high tensile steel which has been heat-treated
and really does not like being welded. Also, if you just cut a tube
'square' to slip the shaft components into for welding, the weld
forms a 'ring' of weld and considerable heat all in one location
on the HT material.

I
was told to cut the tube to create a 'Birds - mouth' joint which
has the effect of doubling the amount of weld which can be applied
and spreading the heat over a longer amount of shaft. Also, if the
weld does fail, the two components are still 'locked' together and
cannot rotate easily - perhaps giving you some warning that your
steering wheel is about to part company with the rack. I was convinced.
The
Engine.
I
had the Ford X - flow lurking in my garage for 17 years. It had
seized up when I came to inspect it. One of the plugs was out and
that bore had gone rusty. A dose of diesel down the pot eased it
off and I thought all would be well. It wasn't. I really should
have taken the trouble to strip the whole thing down, as when I
came to start it, it didn't want to know. So, out came the engine
for an investigation. I found that all the piston rings were 'welded'
in their grooves, and that the sump contained a semi-solid mass
of yuck, which if it had ever got into the oil -pump would probably
have caused it to burst. New rings, after a glaze busting session,
and a good clean out of the oil system did the trick: it didn't
go first time, but near enough.
I
acquired a set of DCOE 40s jetted for a 1600 motor. If you buy these
second hand I suggest you take the covers off the float chambers
and inspect the brackets which hold the float pivot pin in place.
One of each pair on my carbs was broken as I discovered later. To
mend them is not impossible but it involves fiddly riveting. However,
spare tops are available (at a price) so all is not lost. The Weber
linkage mechanism which is designed to allow the cable to come in
above or below the carbs is a god bit of kit in my opinion. What
I can't understand is the high price charged. However, what it does
is amplify the amount of pedal movement so that a tiny movement
of the throttle translates to quite al large movement at the butterfly.
If you look closely at any modern car you will find that the amount
of throttle pedal movement is small - it makes for happier driveability
and control. I had to use the linkage which uses bottom cable entry,
but things get congested in that area if you are using the mechanical
pump.
A
Ford top - entry distributor will just fit under the carbs (depending
on your manifold) but a Fiesta Bosch type is better and can be fitted
with a side entry distributor cap. It also gives you electronic
ignition. I don't have any vacuum advance and it seems OK. I found
it necessary to chop the oil filler off the rocker box and weld
it at the aft end so that it cleared the bonnet.
Right
from the start I had aimed for a 'four wheeled motorbike' concept
so I have little intention to fit a hood. 'Brooklands' screens were
fitted and then some thought was needed on seating. As I reasoned
that as everything would get wet, the seats would have to be capable
of drying out. GRP shells were a possibility but they looked a little
uncomfortable. So I settled for the traditional squab and backrest
design a -la the original Lotus 7.
PVC
upholstery would trap the water in the seating foam, and past experience
of owning leaking sports cars told me that mould and smell would
be the result. Leather is really the only option and I was lucky
in that the guy who makes the bunk cushions for my boats happened
to have half a hide of super black leather. The foam was placed
on Marine ply backing boards which I sealed with -you've guessed
it- Epoxy! Now, if the seats get wet I'm hoping that the only detrimental
effect will be a damp backside as the leather is able to 'breathe'
(unlike PVC).
Heavy
duty 'Velcro' holds all the seating in place held down with contact
adhesive and Monel staples (which won't rust). The SVA examiner
was happy enough that this was a secure fastening for the seats.
It also enabled him to quickly inspect the lower belt mountings.
Upper seat belt mountings are more problematic.
The
design of the Locust body does not come high enough to bring the
top mounting at a level where a tonneau could cover the belts and
still comply with the 'regs'. The top mounting has to be above the
body line and thus the belts would poke through the cover. I anchored
the top of my 4 point belts to a bar welded across the roll bar
just at the level of the body. This is too low. So a bolt-on belt
guide was made to raise the effective height to that required by
the 'regs'.

This
part was fixed to the back rest which I had extended upwards from
the position shown in the plans. Now the car has passed the SVA
it would be possible to go back to the original height to allow
a tonneau to fit over the load area and seat belt mountings. You
can test the mounting height by making a test block and gauge stick
as described in the 'Kit Car' SVA guide. You are looking for a height
from the seat 503mm to the top mounting (or EFFECTIVE height) at
a point 136mm forward from the backrest at squab level.

Building
the car started in mid 1996, and the SVA test took place on the
28th April 1999, so I guess that three years is the time it has
taken to finish the job. It has not seemed a long time. I have enjoyed
every moment - yes - even the SVA testing procedure.

Like everyone
else, there were periods when nothing got done due to lack of time,
or lack of money. I'm glad I chose a locust because it represents
more of a challenge than merely bolting a kit together. The resulting
satisfaction is so much the greater. If you are in the middle of
a build I wish you well - keep going and watch the quality. It's
not worth rushing or bodging the job.
Bob
Fenton
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