Having seemingly totally destroyed our car the next stage of the job was to get the rebuild process started. The first part of this process was to get the chassis overhauled. It would need to be sand-blasted clean, have some badly corroded tubes replaced, re-powder coated and then re skinned with aluminium panels. There was really only one port of call for these jobs - Arch Motors, based in Huntingdon. Arch has been making Caterhams since the beginning, and so it made perfect sense to return our car to the place she was originally created.
Like many of the suppliers we have come across during this process, Bruce Robinson, who runs Arch, is one of the nicest people you could wish to meet. With a genuine passion for the product Bruce was happy to discuss and advise, and with his in depth knowledge of the product and processes involved, we soon had a list of potential jobs that we could get done while the car was with Arch.
We borrowed Mark’s car and trailered our rather pathetic looking chassis up to the factory. We also delivered all the other metal parts, so that they could be cleaned up and re powder coated – items such as the FIA roll bar, wishbones, a-frame engine mounts and de dion tube. All these are produced by Arch – in fact, just about anything metal and black on your car will have been produced in these workshops!
We arrived at Arch in the afternoon where Bruce and his brother helped us unload…
We left the chassis in the sun, Bruce got his pad, and we walked around it discussing what we wanted done, or rather what needed to be done!!
This inspection confirmed some interesting facts about our chassis being a very early ‘prototype’. We know that it was built by Caterham for Caterham as their ’95 show car, where it was the first car to be fitted with the ‘new’ S-type seats, and also it seems one of the very, very first cars with a tunnel mounted hand-brake. In fact this photo would actually suggest it was the very first!! You can see where the handbrake bracket was welded to the car. Someone then realised it was too far back to be used easily, so it was ground off and moved forward a few inches!! Bearing in mind all the interior tunnel top panels are made to fit this later dimension, it would suggest this mod was done at ‘first-build’ stage!
Bruce also pointed out a few bits on the tunnel which now have additional struts – he’ll put these on our car, which will make quite a difference in stiffness of that area, and therefore twisting.
So, we said farewell to the car…
Once we arrived we spent half an hour surveying the chassis with Bruce, and deciding exactly what needed doing to it. We identified some of the smaller tubes that would obviously need cutting out and replacing due to corrosion, as well as some larger sections. The rear ‘basket’ section was particularly bad, with the exposed tubes around the de dion tube and a-frame coming in for particular wear and tear. It is more cost effective for Arch to simply cut this lower section away totally and replace it with a new lower frame. This ‘repair’ ends up being as good as new, simply because the process involved is the same as when the chassis was originally manufactured – indeed the same jigs will be used, so there is further peace of mind that everything will be 100% as it should be.
The front end came in for some particular attention. Whilst the main structure was pretty good, it soon became apparent that there were quite a few smaller sections that would benefit from being cut out and replaced, including the lower cross-members at the front of the chassis, where the car has been jacked up. I was also slightly concerned about the rust on some of the tabs and brackets for the front suspension where the wishbones are mounted. After a bit of thought, I decided to take the big step and replace the whole front end. It wasn’t totally necessary – the original one could have been repaired. I admit I had some ulterior motives for taking such a big step – a new front end would mean we had the most recent front suspension and steering geometry, which in turn would mean we might be able to upgrade to a ‘wide track’ front end, and would also benefit from more up to date anti-dive geometry. In the end it came down to the fact that if we thought we would ever want to do such a thing in the future, now was the time to do it. This justification, to myself, for upgraditis would become apparent throughout this project!!
Other areas we spoke about were adding any bushes into the chassis for things like roll cages, and watts linkage mounting frames. Will we ever use them? Who knows, but at least we know they are there – just in case! I also wanted to add some strengthening gussets to the differential mounts.
As far as the re-skin process we had specified powder coating all the panels, including the cockpit and engine bay. Apart from looking very smart this would also give us more protection against corrosion and grime on a car that is very much used all year round, whatever the weather or road conditions.
We turned away and left our car (or what was left of it!) in the capable hands of Bruce and his craftsmen.
Boxed up the bits…
Carried the chassis inside the factory…
And set off home with an empty trailer….
So – what are we having done to the car?
This is a once-every-15-years opportunity for us, made possible by you lot, our friends from Blatchat and the club, for which we are eternally grateful. You can see from all these pics that without it the car was probably due to fall apart any day soon!
We are unbelievably lucky that most of the work will be covered by our gift, but we are going to pay anything extra in order to get everything done that we want - now is the time to get any work done on the chassis, even if some things we may not use for now, or even may never use…
So, after talking to Peter C, Gar at Freestyle, Bruce and many others we are having the following modifications made to the chassis:
All bushes that are not already there for things like cage, side-impact etc – we may never use them, but at least they will be there – just-in-case.
Removing the front tabs for the old style coolant bottle – little things like that. There is more of this stuff which as I write this I have totally forgotten – Bruce has the list so I shall refer to that later!!!
Now, due to the method of construction, it is very easy to repair these chassis. Any damaged tubes are simply cut out and a new one is jigged up and brazed back in, with no detrimental effect to the chassis or its integrity. The obvious places that Bruce looks at is the rear ‘cage’ – the thin tubes that hold the rear panel and fuel tank – these are usually pretty bad as they are constantly exposed to the elements and stone chips etc, as well as jacking damage. Similarly, the front lower cross-member is usually a bit pitted and perhaps dented from jack use, and general road wear and tear. This was certainly the case on our car, as you would imagine!
At the rear we also have a (very rusty) old style wheel rack. I want to keep this feature, as I have said before; it works as a brilliant rear bumper. Newer ones have a number plate support made from tubing – ours is the older sheet one, and is falling apart and bent. It was decided that the easiest thing to do here was simply replace the whole cage, spare wheel bracket and all. The top rail is retained (the top of the boot) as is some of the rear boot structure, but the rest is replaced. This is a pretty standard thing to do if enough of the tunes are in a poor state. I’ll prepare some illustrations showing all this later…
Moving to the front, we had more of a dilemma. Most of it is fine. Bruce looked closely and it soon became apparent that quite a few tubes needed replacing. Front, lower cross-members, as mentioned, but also some of the quite this suspension mounting brackets were in a pretty bad way – they are only about 2-3mm anyway, so any significant rust here is not good. We had also thought about seeing if we could change these so that we had a more up to date front suspension geometry, but it had not seemed really viable. However, on looking at the work that might need to be done we seemed to have approached the point where we said, well actually, do we just put a new front end on. We hummed and harrrred, and decided to go for it. As I say, this is a one-off process, so it would be shame to not do everything we can to extend the cars life and use! We’ll pay a little more for the new steel, which is fine.
Someone mentioned about if we felt bad changing a ‘historic’ Caterham!! Well, it’s not really historic – yes, a show car and maybe the first with tunnel hand brake etc etc, but in the grand scheme of things it is not an ‘important’ car! Far more important is that it is used and enjoyed by us. It has taken us to far flung places, thrashed round airfields, flowed round circuits and done the shopping run! It is not a ‘polished’ car that sits in a garage and comes out a few times if the sun is shining, sitting un-taxed and un-used for the winter months, like many. We’ll never sell it, and of course are hugely attached to this specific Caterham. But we want it repaired as best we can, in order to extend its life as much as we can. So I don’t feel bad about replacing 30% of the chassis with newer bits! If any part of the chassis is unique, it is the cockpit area, and that we shall retain!
I have also decided to fit lowered floors, on both sides. Our original (very early, first fitted!) S-type seats had broken frames – a very common failure. This meant that the seat back actually leant back much more than normal. This meant our heads were nice and low in the car. When we fitted our ‘new’ second hand ‘S-type’ seats, we discovered that seat backs that were not broken, and therefore more upright, lifted us up in the car quite a lot. When you have driven over 90,000 miles at a certain height, a change of 25-30mm is very noticeable. For a start, with our broken seats we were low enough to crouch behind our Brooklands screens in bad weather, where as with the newer un-broken seats we always looked over. Same with the carbon half doors we have – a lowered driving position means my shoulders are below the edge, where as a higher position means my shoulder hits the top of the door and pushes it off the car!!
So – another expense, but worth it I think.
We are also having all the internal ali panels powder-coated – it will help with future corrosion protection and make everything look neater.
Because of my desire to record the whole of this process I have spoken to Bruce and he has very kindly agreed to let me go up and photograph each stage of the rebuild process whilst the chassis is at Arch. I am very conscious about not getting in the way, they are very busy at the moment (for various reasons!) but Bruce has said its fine, and I hope to maybe even be able assist in the construction of the car itself, which will be really special.
I have arranged to visit Arch again next Saturday when the car should be finished off. Bruce has been very kind and agreed to let me help with this stage (not a normal service!!) – I’m very conscious of not getting in the way, but it will be nice to help rivet and fix the final few panels, and see how this stage is done. Even if you get your brand new Caterham in its most basic kit form, all this panelling will have already been finished, so it is a unique opportunity to take part in this process and will make our car even more ‘ours’ – if you see what I mean!!
Everyone knows the recent big news with regard to Caterham chassis, and for sure it will mean big changes at Arch, some of which are already happening. I have been lucky enough to visit Arch a few times, and I could spend days walking around, watching craftsman at their work. I love it, and you could not hope to meet a nicer or more helpful person than Bruce.