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Discussion Starter #1
i've read about how the aluminum frame is made with such a unique process, and is different than all other cars...

does this basically mean if you're in an accident and have frame damage, you're screwed?

would a local lotus dealer even be able to fix it? would it be ridiculously expensive?
 

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Nope, frame damage would require frame replacement. It has to be a signifacant crash to damage the frame though. There is a fibreglass structure in the front for frontal impacts. This structure absorbs the impact and is replaceable.
 

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True, but....

You can also write off the aluminium chassis by sliding sideways against a kerb for instance and damaging a wheel.

This could tear or bend the attachment points of the suspension wishbones to the chassis, although the wishbones are designed to bend/fail first it doesn't always work.

Attachment points can't be repaired either, so it's chassis-replacement time as well.

The front is most vulnerable in this respect, as the rear suspension is partly attached to the (steel) engine subframe, which can be replaced separately.

Basically *any* damage to parts of the the chassis that are glued in place (aka. most of the major bits..) can not be replaced/repaired.

Still.. The biggest cost factor in this job is the labor time. The replacement chassis itself (with windscreen, pipes and other stuff already in place) is not that horribly expensive.

A guy in germany or switserland is doing a re-chassis on his crashed S1 by himself.

Bye, Arno.
 

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Arno said:
A guy in germany or switserland is doing a re-chassis on his crashed S1 by himself.
yeah, that's me :D

A chassis swap is quite a straight-forward job. The manual talks about 60 hours of labour time whereas the body assembly (sill panels, windscreen framed, crashbox factory-fitted) is only about 6.000 Euros. Worst thing: the lead time for the body assembly, I should take delivery of it tomorrow after having waiting 3 months, but I will not take any bets on this. However - this is an S1 chassis made to order, a S2 chassis should not have a lead time of more than 2-3 weeks :rolleyes:

re the possibility of chassis damage:
my crash was a hefty side impact, I lost control in the mountains due to black ice (in September...) and slid into oncoming traffic. The chassis did a very brave job, because of the impact point and the velocity involved I am not really surprised it bent. Arno is right in saying that the chassis does have some weak spots - the worst IMHO the mounting of the front suspension which cannot really be repaired if bent (well... it de-facto can, but this is not "official" Lotus view). If you cannot avoid a crash you really should head for a full frontal impact - the crashbox works very well compared to the other areas.
 

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Hi!

I repair frames in GB in last summer.
The biggest point of this is to get the aluminum profiles. You can't get it, because these are not public.
So the only way to get some chassis parts is to dismount a second crashed frame, and from this you can get some profiles.
The industrial method is to bond these parts together with a glue, what is dry on higher temperatures. If the frame is ready, you can't replace any part with the same glue, because you can't reheat the other glued sections.
So you must search for a glue, that is strong enough, and work on normal (room) temperatures.
If you have all the parts, what you need, and the glue, there are no problem to repair a frame.

Cheers: Charles
 

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zvezdah1 said:
Doesn't the factory recommend replacement of the chassis for big damage?
Chris
I think the facory recommends you replace the chassis after even a fairly minor ding if it takes a big load it's not supposed to.

Craigy
 

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zvezdah1 said:
Doesn't the factory recommend replacement of the chassis for big damage?
Chris
Hi!
That's the point! The factory say it for the smallest damage: REPLACE.
For they it isn't a business to do something on the chassis, and the whole technology is designed for produce, not for repairability.
This kind of system have his negative effects also for the factory Lotus itself, because there are the problems with the corrosion in the footroom.
Now, the customers say: ok., this is a damage, so replace my frame please!
But Lotus say: no, this is only some Cosmetic problem...
Lotus still work on this problem, hopefully they can solve it.
This corrosion problem doesn't exist so often on S2 modells, but the federal Elise is a totally other theme in this case. :D
(For me, the Elise is still the one of the best cars on this planet!)

Cheers: Carlos
 

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Just to put my .02 in there. I used to work for Ferrari of Houston in the collision shop int he mid to late 90s. That being said the 360 modena came out after I left that shop. I occasionally swing by from time to time and talk to the shop manager that I used to work for and check out the new models close up. He said the 360 modena (another aluminium chassis) is repairable. BUT if the parts are bent they must be replaced. Aluminium especially extruded work hardens very easily. Meaning it will bend but when you bend it back the metal grain structure shatters and larger pieces just come flying off when under normal hydrallic pulling pressures.

The repair procedure for the 360 is you put the car on a chassis jig. You start at the opposite end of the chassis from the wreck and insert the jig pins. When they stop lining up you start replacing parts. So I guess the kicker is if the parts are available then yes it can be fixed. A jig would be great but not necessary imho. There are a number of chassis measuring systems that will allow you to build a schematic. I believe the chief veloicity, caroliner and definately the shark measuring system allow you to do this. These computerized measuring systems are common place in reputable shops these days. The key is to have it measured and save the data BEFORE you wreck the car. Then go back to that repair shop if you need to have the chassis looked at as I dont' think lotus will have any jigs over here nor will they have any collision repair shops. I will give y ou a gold plated guarantee the chassis measurements will not be in the computerized measuring systems data bases. If you happen to get in a wreck in houston with the elise drop me a line and I will hook you up at the Ferrrari dealership. Steve won't like the repair but he will do it.

The adhesives question I can definately answer . Yes there are room temperature structural bonding adhesives that will work just fine. I have seen a car at a trade show that was back halfed with all new parts. They welded none of the parts back together but bonded them instead. They then crash tested the car graciously placing the rear bumper in the back seat. NONE of the bonded joints failed. Instead the steel tore apart around the bonded joints. Fusor was adhesive the manufacturer IIRC. But 3M makes some as well as duramix and a host of others. Structural bonding is somewhat common in the repair industry. Especially panels that require a lot of additional parts to be removed for welding such as roof panels. No welding just drill out the spot welds, remove the damaged roof and glue on the new one.
 

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The Lotus Service Notes (for Lotus Elise MY 2001 onwards) states exactly the following:

"The bonded and rivetted alloy chassis structure is considered a non-serviceable jig built unit to which no structural repairs are approved. Superficial, cosmetic, or non-structural localised damage may be repaired as necessary, but in the case of accident damage resulting in significant bending, tearing or distortion of the aluminium chassis, such that the specified geometry cannot be achieved by the standard range of suspension adjustment provided, the recommended repair is to renew the partial body assembly, which comprises the chassis and roll over bar together with jig bonded composite rear bulkhead, body sills, windsreen frame and crash structure, and the radiator feed and return pipes, heater pipes, battery cable and clutch pipe which are all routed with the sill panels."

As simple as that....:)
 

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zvezdah1 said:
I was thinking it's a lot like the motorcycle helmets, they say once you take a hit with it to toss it, because of stresses to the whole construction>
Chris
A bit OT....

Motorcycle helmets have a styrofoam crush area in the shell. Once compacted in a certain area, that area stays flat and offers far less protection should an impact occur in that same spot.
 

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do you know about SABS in houston? they fixed a frame damage on a prowler, Sabs told me they had to cut the bent part and fabb a new one, then welded it back on.
http://www.sabsconversions.com/prowler1.htm

LittleRocket said:
Just to put my .02 in there. I used to work for Ferrari of Houston in the collision shop int he mid to late 90s. That being said the 360 modena came out after I left that shop. I occasionally swing by from time to time and talk to the shop manager that I used to work for and check out the new models close up. He said the 360 modena (another aluminium chassis) is repairable. BUT if the parts are bent they must be replaced. Aluminium especially extruded work hardens very easily. Meaning it will bend but when you bend it back the metal grain structure shatters and larger pieces just come flying off when under normal hydrallic pulling pressures.

The repair procedure for the 360 is you put the car on a chassis jig. You start at the opposite end of the chassis from the wreck and insert the jig pins. When they stop lining up you start replacing parts. So I guess the kicker is if the parts are available then yes it can be fixed. A jig would be great but not necessary imho. There are a number of chassis measuring systems that will allow you to build a schematic. I believe the chief veloicity, caroliner and definately the shark measuring system allow you to do this. These computerized measuring systems are common place in reputable shops these days. The key is to have it measured and save the data BEFORE you wreck the car. Then go back to that repair shop if you need to have the chassis looked at as I dont' think lotus will have any jigs over here nor will they have any collision repair shops. I will give y ou a gold plated guarantee the chassis measurements will not be in the computerized measuring systems data bases. If you happen to get in a wreck in houston with the elise drop me a line and I will hook you up at the Ferrrari dealership. Steve won't like the repair but he will do it.

The adhesives question I can definately answer . Yes there are room temperature structural bonding adhesives that will work just fine. I have seen a car at a trade show that was back halfed with all new parts. They welded none of the parts back together but bonded them instead. They then crash tested the car graciously placing the rear bumper in the back seat. NONE of the bonded joints failed. Instead the steel tore apart around the bonded joints. Fusor was adhesive the manufacturer IIRC. But 3M makes some as well as duramix and a host of others. Structural bonding is somewhat common in the repair industry. Especially panels that require a lot of additional parts to be removed for welding such as roof panels. No welding just drill out the spot welds, remove the damaged roof and glue on the new one.
 

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I haven't heard of them. But that doesn't mean much. lol.

Fabbing a new structural part is not a good idea IMHO. The metalurgy information required to replicate the part simply isn't available to the general public.
 

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choi0706 said:
do you know about SABS in houston? they fixed a frame damage on a prowler, Sabs told me they had to cut the bent part and fabb a new one, then welded it back on.
http://www.sabsconversions.com/prowler1.htm
The Prowler has a frame that was originally designed to be built up via welding so that repair technique may be satisfactory. The Lotus frame is as light as it is because it was made from thinner aluminum extrusions intended to be bonded together. According to the Lotus engineers, to weld the extrusions, and retain the same strength, the extrusions would have to have been thicker (and thus, heavier). The Lotus is not made like a Prowler, or XJ or A8 where that may be possible. I would certainly never drive an Elise in which someone had welded the frame together.
 

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I'd like to bring this back from the dead. I've got a question regarding a car I've been thinking about buying (read: fixing). It's an 07 Exige; the front it total crap. Crash structure is gone, oil cooler, clam, lights, etc...BUT, it has a clean title and a great price. The damage I'm worried about is the forward most connection to the upper A arm. It's been ripped up and away (but all the other joints are ok). It looks like this housing for the A arm joint crosses the front of the car and connects the other A arm. It is bonded all the way? There is no chassis damage as this was a 'front swipe' kind of accident. The guy is selling a new chassis with the car, but I'm wondering if I could fix this damage before I spend eternity removing and replacing parts. Are these parts (structural aluminum) available? I know the general consensus on LT is to just replace the frames, but the aluminum is very thin (1/8"?). I cannot imagine it carries much load at all.
 

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Bump, any ideas?
 

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Your are in uncharted water fixing the frame. I have a track car that we bonded a steel cage to and it had minor frame dmage that did not involve suspension pickup points and, given the added strenght of the 8-point cage, I made the decision that I'd simply re-bond the suspect area and call it good. I'd never fix a road car this way and you are nutty to take any chances fixing a suspension pickup point on a road car. Save the money you would have spent fixing the car and buy a solid, unwrecked, car.
 

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How are you folks just "replacing" the chassis? The only way I know is with a donor car that has been checked on a Lotus chassis rig (of which none exists except in two locations in the UK).

Lotus will not sell chassis only replacement ... has this changed? This IS the reason I've changed my mind about doing full contact racing series (read World Challenge series) -- getting replacements chassis requires buying a new Elise complete or a used one that has no chassis damage.

Before I go race my Lotus I had planned to do a full 3D measurement so I have correct reference points to which I can compare over time.

Also wondering if it's cheaper to build alternative replacements to improve front an rear geometry that is NOT bonded -- for race applications only.

Of course the best solution is getting Lotus to SELL CHASSIS ONLY! If someone lurking from Lotus (or indirect lurking of a lurker) could post why the Chassis Only isn't available for sale, that would be most appreciated.

Rob.
 
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