Will it pull?

This weekends job was to get the race car onto the jig, and have a go at pulling it straight.

First order of business was to get the blue car off the jig, and out of the way.  As it needs to be dismantled anyway, figured I might as well cut it up now – moving 1/3 of a car is a lot easier than a whole one.

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Front end off, in two pieces, and out of the way.  Until I get the windows out of rear section, I’ll leave it in one bit.

So, this leaves me with the replacement piece, roughly cut out.  Its a big piece!

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With that out of the way, its time to make sure everything on the jig is still square, that its all level etc.  The blue car was damaged in the left front, so at this point I wasn’t 100% confident that it was totally straight.

So with the car out of the way, it was time for jog work.

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Using measurements, I got the left front sil clamp made up (blue one was crashed here) so that it was level and square with the other side.

Made sure that the front cross member was perfectly square and level when compared to the rear subframe, so that she ends up straight once I’m done.

Now that the race car was back on the hoist, it was time to pull the rear suspension and fuel tank out, so that I could drop it onto the jig.

Lowering the car onto the rear subframe, and bolting that up, we moved around and attached all of the sil clamps.  They were all with 0.5mm of fitting, with one taking a little love with the hammer to slip into place.  So far so good.

Dropping the bolts through the front rails they slotted perfectly into the front subframe – nice!

With that all done, it was time for a ‘FULL PULL’  (Frequently yelled out at tractor pulling contests in the southern states of the USA – http://fullpull.com/)  I know, I need to watch less USA motorsport tv, and probably less US tv in general…

So, with the pulling arm attached to the frame, the hook onto the car we start jacking.

Its moving – that is promising!

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Letting the pressure off, it springs right back to where is was to start with.  OK, so more force needed.  After putting a lot more in it, the section of the car that I’m pulling on (which was already ruined) starts to crush.  Hmmm, this is already much harder than what I did on the blue car – stupid roll cage.

So, after a bit of persuasion with the hammer, we get the hook onto a more solid, although already ruined part of the car and tried again.  We get past where we got before, and its not crushing, that’s good!

A few more pumps, and the hook is starting to straighten out, release the pressure again.  At least this time the car has settles back 10mm further out than what it was originally.  So the hook goes into the press to be squished back into shape, and I cut another hook out on the mill.  Then welded both hooks together to make one 20mm thick solid steel monstrosity

Try again.  Everything holds this time, although the car is starting to deform a little where the hook is, its bending the 5mm plate that I put in there to spread the load.  Next was a sequence of pulling until a measurement was reached, then relaxing it to check its location.  Then repeat…

During each pull, the creaks and groans from the car was a bit unnerving, and nearing the end of the process, BANG.  After cleaning up after myself, we have a look and the car has popped out of one of the rear sil clamps.  Loosen that off, take the tension off the puller and sits back into place.  Do it up tighter, and try again.

We finally get it out to where it needs to be, ending up moving it out by 55mm to make everything line up again.  Of most interest was that we had to stretch it out to 85mm to get it to settle here – thats 30mm of over stretch – and was a lot more than I was expecting.  Every time you bend metal, you know that this is going to happen, but this was a long way, especially when you are sitting there watching it.

And there it is, in theory at least, all straight.

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With all of that completed, its was getting late and the next step is going to consist of hours of using the angle grinder, I figured I’d wait until the following day for that.

Another job on the to do list is to start unpicking a couple of bits off the blue car, so that I can join the thing back together even stronger than out of the factory.  There are many pieces that are 3, even 4 layers thick, so to do this properly, you need to remove parts of these layers so that you can get inside it and weld all of the layers, one by one.

This means another 1000 or so spot welds to remove.

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Its now Sunday afternoon, just enough time for an hour or two on the saw and the grinder to get the race car stripped of all of the pieces damaged beyond repair.

This leaves you with a rather large hole…

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From the front, it doesn’t look any smaller.

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Last job of the day was to start accurately preparing the A-pillar for the transplant.  The three joints that I am going to make are all at natural joins of the car, so this bit worked out really nicely.

On the blue car the very inner skin will be totally removed, as I’m using the complete inner section from the race car.  The middle layer will still be attached to the rest of the blue car, and the outer layer will have been completely removed.  So when the blue car is offered up for the last time, I’ll be able to weld up all of the joints. that are internal to the a-pillar.  The outer skin will then be put on over the top and welded on, making a repair that will probably be even stronger than out of the factory – and hopefully just as straight.

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Next weekend is a case of doing the same at the bottom of the a-pillar / sil and also out at the front radiator support, and then accurately cut all of the floor and scuttle panel so that they can simply be butt welded together.

I can tell you one thing, moving the cage out was at least 5 times harder than pulling the same area out on a the standard car, and this is an area of the cage that has no triangulation that would stop the bars moving back to where they need to be – everything was in the same plane, so should have been easy to bend back.  It is very easy to see how these cages add such a massive amount of strength to these cars in the areas where they are triangulated.

So I’m fairly happy with all of this as the question ‘can I get the cage straight again?’ was my biggest worry.  The work is not done by any means, but now that the cage is straight, the rest of this is something that I know I can do – its just a matter of time, angle grinders and welders.

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