Hi everyone!
Loads of things have happened since the final so
I thought I would put pen to paper (or printer to
paper) again and put some of them down here!
Straight after the final, when we were still enthusiastic,
we started to make plans for next season. One of
the main problems was fitting the driver in the car.
Although we had taken careful measurements and checked
constantly throughout the build, we found that Sarah
would not fit in at the final. Tom, with his shorter
legs was fine and it was him that we had used for
all our measurements. So plans were made to move
the steering bar linkages from behind the front axle,
where they were in the way of the drivers feet, to
in front. This meant making a longer steering rod,
and putting the steering arms above this. The bent
steering support was also replaced. Then a whole
domino effect of changes were needed. The seat back
(which is also the roll bar) needed to lay back more.
The motor was stopping this. The only place to put
the motor was behind the wheel (to push instead of
pull) but the batteries were there. Move the batteries
to the sides of the car, the bodyshell would not
now fit! It was decided that we needed to do all
of the above changes and gulp! this would have to
include the making of a new bodyshell. (more of this
later!) As we were moving everything we also took
the opportunity of lifting the car a little to increase
ground clearance and moving the right hand rear wheel
and brake to allow a slightly wider track. New motor
supports were also made as we felt that the chain
was losing tension because these were bowing. A link
has also been made to join the supports together.
The roll bar was re-bent and raised to comply with
the rules for driver safety and a new support bar
made to get the triangulation that is needed.
The car was also filmed in the studio and using
footage of the car racing, a short DVD has been produced
by Matt. The plan is to send this to prospective
sponsors and hopefully it will be different enough
to attract attention! The video can also be viewed
on You Tube, just search for Crag Rat.
The bodyshell! Making a bodyshell is always a massive
undertaking and a decision to make a new one was
not taken lightly. The original plan was to make
a Styrofoam plug, fibreglass this to get a mould
and then if possible use carbon fibre for the actual
shell. I emailed off to several companies mainly
to see if I could get some scrap/offcuts of Styrofoam.
One of these companies emailed me back and offered
to actually machine the whole plug in Styrofoam for
us! What a result! Our enquiries in the use of carbon
fibre revealed that it would give us no advantage
over fibreglass in terms of strength or lightness
and it would be massively expensive. Commercial carbon
is laid into the mould and vacuum bagged and placed
in an autoclave which would not be possible in school.
Thoughts then turned to if we wanted the look of
carbon what else could we use? It was decided to
approach large scale vacuum forming companies to
see if it would be possible to make a shell in carbon
fibre look ABS and use the plug as the mould. After
loads of emails, we finally found somebody who would
be willing to do this for us! Fantastic! Mr. Bolger
designed the bodyshell on Pro DeskTop. The shape
is loosely based on the Volvo gravity racer and looks
absolutely stunning! The hope was to convert these
files and get the shell machined full size. A tenth
scale model was made from foam using our router in
school. This is where the problems started!
After numerous telephone calls and emails to the
original Styrofoam company it became obvious there
was a problem. My emails were never replied to. I
was also fobbed off when I called and was never put
in touch with my original contact. This was really
disappointing and I must stress it was they that
offered to do this work for us and not me asking!
Plan B! Make the mould ourselves.
Again styrofoam was considered. Unfortunately to
allow the mould to withstand the pressure of vacuum
forming it would need to be fibreglassed. The amount
of preparation would be astronomical! Plan C. Make
the mould in wood. The problem is massive cost
and the difficulty of working with this material.
Plan D. Use our own router in school and make the
mould in small sections and piece it together!
This is what we have decided to do! Although time
consuming it is the best solution to our problem.
We were also lucky to source some ‘scrap’ wood.
This came from Masterdor and is the waste wood that
is removed to allow glazing panels etc in their doors.
Thanks to John Tapscott for letting us help ourselves!
We have made a start on this but coursework has to
take priority on the machine at the moment and although
we have made some pieces the main bulk will be started
shortly.
We were very lucky to get some sponsorship
from Harewood Hill Climb. They had noticed the article
about the 2007 final in the Knaresborough Post. The
links between us and motorsport are very obvious
and we are very grateful for their interest! Dale
Cordingley brought his race car into school for us
to have a look at and there is a separate story about
this further down this page!
Currently we are looking at the electronics for
the car. Essentially they will be the same as last
year, however we do have plans to improve on them.
Accurate current measurement is essential and this
will be a priority. We are also looking at restricting
the amount of current the car will draw. This will
also be in conjunction with a timer which will record
how much capacity has been used. For example, if
we have a problem and lose time on the track, the
car will be allowed to go faster for the time left
on those batteries. This will be controlled through
a custom made speed controller. As regular readers
will probably know, my electronics knowledge is sketchy
at the best! I am really grateful to Dave at Marell
who has again agreed to do this for us. It will be
interesting to see how cars fitted with Nu Vinci
hubs get on. My feelings are that they may have a
bit more friction than claimed and not be as efficient
as the Rohloff but we will have to see!
I hope to start writing a bit more
in the diary over the next few weeks so keep checking
back! We are constantly looking for sponsorship and
if you feel that you may be able to help us out,
please contact Mr Hutchinson on 01423 866061 or the
email kjsgreencar@googlemail.com.
Check out the student crag rat website at www.thecragrat.co.uk.
Thanks for reading! |
