A Sand Rover roll cage is born!
Hi and welcome to a brief glimpse at what it
takes to fabricate an alloy
roll cage for a vintage tamiya sand rover.
Before i start to fabricate anything i always
wear the necessary safety goggles and respirator
this is always good practise before doing anything
with machines etc and also stops you looking an
idiot in front of Nurse glady's emmanuel down
at your local accident and emergency
(you have been warned)
The following pictures show what we want to achieve
Ok so we need to next look at materials for a
job like this
To start with, a job is only as good as the materials
you use, you will see 1 x 8mm solid rod, 1 x 6mm
solid rod, 1 x 8mm hollow round tube and
1 x 3mm threaded stainless rod.
The fabrication.. 2 x legs
First we need to take an over long section of
the 8mm solid bar this will be the leg sections.
lay out an old sand rover leg and mark with a
pencil for the first bend. Keep bending it until
you end up with the same profile as the original
You will also notice i've marked out for where
the first cut should be.
Next you will see its been cut and filed nice
and flat also notice the shoulder / notch in the
bottom of the leg
this will take some time to achieve and is essential
for the perfect fit so time taken here will be
time saved in the long run. We need to obviously
do this twice as there are 2 legs believe it or
not!
The next step brings us to the other end of each
leg. For this stage I use a 12 ton hydraulic press
this is to flare the end to the same thickness
as the original leg. Again mark it out as per
original part
and use equal hydraulic pressure. This is essential
to make sure both legs are the same
It looks a little rough here but we will clean
this up soon.
The next step is to mark out for the hole for
the roll bar to go through, we need a 6mm hole
here
which is bigger than the original but the centre
must be in exactly the same place as the original
part. I drill this now so we can work and trim
the alloy around it and it shows a lot easier
where we need to be
The following picture
now shows i have trimmed up both alloy legs around
the hole to give them their final appearance.
Double checking any measurements before you drill
and file is a great idea and avoids a lot of heartache.
And finally the last stage of the legs is to
drill and tap out for our 3mm stainless threaded
bar.
Tamiya's original leg has a captive 3mm nut but
we don't have the room for this. So drill at an
angle following the length of the leg then it
needs a thread tapping in then screw in your bar
and finally bend it down into a position where
it will go through the hole of the body shell
This is also an ideal opportunity to check they
fit properly. Make sure both legs are parallel
with one another and that they are of a similar
angle to your original.
Now is a fantastic time to get your wife/ girlfriend
to put the kettle on and have a cup of tea...you
have earned it !!!
The Roll bar
I'm now going to make the centre of the roll
bar using our 8mm hollow tube. Notice the original
part has a chamfer to it and we are going to copy
this using either a file / or sanding carefully
A lathe could also be used.
When using a fine file or sanding machine be
careful not to mark the face of your alloy,
The best way of getting scratches out of aluminium
is not to put them there in the first place!
If you do however, use some fine wet and dry of
varying grades.
Once a chamfer has been put onto your tube mark
it for length cut it and chamfer the other side.
This picture
shows the final piece slipped over our 6mm rod
to show you what it will look like when finished.
Now we need to cut a 300mm length of 6mm rod
and put a centre line on it then line it up with
the original roll bar and mark with a pencil your
first curve/bend, if you look at the original
carefully it is slightly flared out i.e not 90
degrees. We need to bend it ,then offer it up
to the original..
Now we are ready to do some assembly by adding
1 x leg then the centre tube then finally the
other leg and making sure both legs are facing
the same way!
Next job is to offer up to the original again
and mark for the last bend , this is harder than
it looks trust me, but getting this right is very
important so taking some time here will stop you
throwing the entire piece at the wall, once you've
made the bend there's no going back!
So now we are getting close to aluminium heaven!..
We next need to over lay the original and cut
off the over long pieces. Now it's worth mentioning
that if you again look closely at the original,
the cut we need to make is not square, it has
a small pitch to it and this is very important.
So i take my time and cut it, finally finishing
it up with a fine file
And lastly as before we need to drill and tap
for our 3mm stainless threaded rod and cut to
length as per original. Once inserted the threaded
bar needs bending to a slight angle
Ah i here you say it's finished !!! NO NO NO
NO....
We need to check that it fits and its square and
it looks gorgeous !!!
The finish!
And lastly when i'm happy with the roll bar it's
polishing time, using fine wet and dry paper and
a product called Autosol paste compound, this
stuff is awesome but don't get it confused with
Anusol which is available at your local chemist
/ drugstore for a very different problem i.e
rubbing bum cream on aluminium is not going to
work!
Thanks for reading this and hope you find it
of interest. A really big thanks also to Moosey
and stevo for providing this awesome site!
They are the Mutt's Nutt's!
John (j-man)
Coming soon to Tamiya101
Making the Hilux off road trailer
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