In that case most of the classic cars on te road should too. Many have had rust and/or repairs to shells or chassis, often using sections cut from
another car.
Complete re-shell, or chassis swap? maybe.
But my spitfire is a good example, I had 3 chassis and I seriously could not remember which one belonged to which V5. They were all identical. I just
built it with the one that had the least scabby bits around the bonnet brackets. Am I driving a ringer? The commission number is attached to teh
shell, but the identity is defined by the chassis, though has no identifying numbers.
Cut and shut usually refers to 2 or more cars welded together, here they have just used repair sections.
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Building: Triumph GT6 replica body in aluminium Built and so
posted on 7/7/21 at 04:24 PM
In my view, no because chassis and monocoque repairs are permitted and happen all the time. Where the material for the repair was sourced is
immaterial.
I'd say no. It's the same chassis but repaired. It's not even a cut and shut. The fact that the repair panel was cut from another
car shouldn't be a problem. I've seen steel cars repaired by welding in a bit of biscuit tin lid. This Elise has the right grade and
thickness of aluminium as its repair panel, even formed correctly. Is it as good as new? Probably not. Does it need in IVA? I wouldn't say
so.
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Building: Dax Rush - very, very slowly....
posted on 7/7/21 at 11:27 PM
my only worry would be the welds - or more what the heat has done to the metal around the welds...
if the original chassis was glued then is the alloy really going to be ideal for welding and/or was it heat treated material that the welding has now
screwed up ?
Awkward one this, given he said Lotus themselves said it should not be repaired, but did they say that because they wanted to sell him a whole new
chassis ( if they still make them now) or was that on safety grounds given they designed the thing to start with... I am inclined to have the same
views as Snapper as far as insurance goes. What if that car crashed into you and was found to be dangerous and the insurance ( and your claim against
it) was invalid?.
Having said all that , the repair seemed reasonable, but I am no chassis engineer.
No to IVA and Q plate - it’s like any other repaired car as others have said.
However…..
I would 100% like to see the engineering verification of the repair methods, and/or the qualifications of the guy who is offering to do similar
repairs on other cars. Structural repairs on steel monocoques are well understood whereas this sort of repair is, at least in automotive terms,
unique. Even better would be to submit a chassis that has been repaired in this way to some sort of torsional rigidity/hydro pulse check. If it
passes, then this guy could be sitting on a gold mine!
Where are the airframe repair specialists? I know there are a few on here, it would be great to have their opinion!
Hes must have replaced less than 5% weight of the chassis, if you had to IVA for a welded repair panel, most 90s/00s fords would have been IVAd 3
times by now!
And questioning welding over gluing... really!? Its a localised replacement, the gluing was done for fun, hes not replaced areas that were glued with
welds, hes just used both methods to join 2 parts of what was originally one piece of metal.
No wonder so few takes the IVA/ringing argument seriously when stupid suggestions like this are made at every opportunity, it just muddies the water
as to what the real issues are in the kit car market.
Am I the only person who thinks that repair looks like crap? Yeah that may be only 5% of the chassis but it's a rather important part. God knows
how that section will behave in a crash and nobody does cos it ain't been tested in any way. I just hope it is not sold on to some unsuspecting
buyer who doesn't realise what's lurking under the bodywork.
quote:Originally posted by Mr Whippy
Am I the only person who thinks that repair looks like crap? Yeah that may be only 5% of the chassis but it's a rather important part. God knows
how that section will behave in a crash and nobody does cos it ain't been tested in any way. I just hope it is not sold on to some unsuspecting
buyer who doesn't realise what's lurking under the bodywork.
Nor has any welding on any steel car and their must be literally 100's of 1000s of cars on the road with mig welded repairs of which a lot would
have had accidents and proved to be fine - or they would ban repairing any rusty chassis.
The tig welding on the inner face looks fine, not exceptionally neat but looks well penetrated IMO. Most glues and epoxies are famed for being
stronger than their parent material, or the Elise wouldnt have become so famed for being glued in the first place. Seems like a lot knees jerking
here.
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Building: Triumph GT6 replica body in aluminium Built and so
posted on 8/7/21 at 04:23 PM
quote:Originally posted by loggyboy
quote:Originally posted by Mr Whippy
Am I the only person who thinks that repair looks like crap? Yeah that may be only 5% of the chassis but it's a rather important part. God knows
how that section will behave in a crash and nobody does cos it ain't been tested in any way. I just hope it is not sold on to some unsuspecting
buyer who doesn't realise what's lurking under the bodywork.
Nor has any welding on any steel car and their must be literally 100's of 1000s of cars on the road with mig welded repairs of which a lot would
have had accidents and proved to be fine - or they would ban repairing any rusty chassis.
The tig welding on the inner face looks fine, not exceptionally neat but looks well penetrated IMO. Most glues and epoxies are famed for being
stronger than their parent material, or the Elise wouldnt have become so famed for being glued in the first place. Seems like a lot knees jerking
here.
From a mot testers perspective, if the bonded repair is visible then it's a straight mot fail as per the requirements, the seam between the
repair panel and chassis extrusion would need to be continously welded (as it is a metallic structure), bonding and riveting is only acceptable where
originally used in the vehicles construction, or where it forms part of the manufacturers approved repair methods (lotus have no approved repair
methods for their extruded chassis).
If the bonded repair is hidden by the bodywork, it would have to pass as the mot is only applied to what can be seen during the test.
I'm suprised that it passed several previous mots with the prior bodge up , from the other videos it appears several aspects of the prior repair
would visible.
As far as the provenance of the repaired chassis, if put to the dvla it would be a q plate and iva by their rules, reuse of sectional parts of a used
body/chassis are not permitted with regards to the vehicle id remaining unaffected.
I have seen in the past new bodyshells being cut up to repair damaged cars which was within the rules even once the sva came in and didn't
affect the registration as the parts used to carry out the repair were new - even though the repaired cars were technically "cut and shut"
it was fine with the dvla.
The same applies with landrovers where a partial chassis can be bought new for the purpose of repairing a damaged/corroded chassis.
With classic cars there is a degree of leniency in terms of registering a rebuild as a "reconstructed classic vehicle" where the
components have to be period but can be from 1 or more vehicles, with no requirements for the provenance of the chassis/body to be from a single
vehicle, just to have been inspected by a respective owners club as correct for the vehicle type and age.
quote:Originally posted by obfripper
From a mot testers perspective, if the bonded repair is visible then it's a straight mot fail as per the requirements, the seam between the
repair panel and chassis extrusion would need to be continously welded (as it is a metallic structure), bonding and riveting is only acceptable where
originally used in the vehicles construction, or where it forms part of the manufacturers approved repair methods (lotus have no approved repair
methods for their extruded chassis).
I think the Mot manual leaves it much more down to interpretation than your statement would infer:
Some vehicle manufacturers have recommended repair methods that use MIG brazing, a combination of adhesive bonding and riveting, or amalgamations
of these with other joining methods. Such repairs are therefore acceptable unless they are clearly inadequate.
It does go on to say bonding isnt suitable for load bearing members, but I don't believe this would apply to mid part of the chassis, especially
as its combo of rivets and bonding.
The roll bar is an attachment point for the seatbelt, any bolt mounting point for the rollbar is classed as a prescribed area, which makes it a load
bearing member in the area where the repair is located.
quote:
You cannot accept the following bonding processes for repairs to load-bearing members:
gas brazing
soldering
adhesive bonding
fibre reinforcement
body filler
Mig brazing is used to attach low strength cosmetic panels to high strength boron steel without affecting the steels structure, as welding to boron
steel makes it brittle in the heat affected zone.
Bonding and riveting is used to attach both boron steel panels and dissimilar metals together, but uses self piercing punch rivets which are a
completely different strength class to a pop rivet, the adhesive is a secondary attachment in this kind of repair as the boron steel is approx
1500mpa, the structural epoxy is approx 25mpa.
Out of interest, could the repair seams be put in a better location? For me I don't know whether having a seam at that position introduces a
weakness in the structure. Would it have been better to use more of the donor material and cut away the original until it was in a 'safer'
location?
I guess it's similar to what obfripper suggests below, having the join very close to the rollbar seems like an unusual decision.
quote:Originally posted by obfripper
The roll bar is an attachment point for the seatbelt, any bolt mounting point for the rollbar is classed as a prescribed area, which makes it a load
bearing member in the area where the repair is located.
quote:
You cannot accept the following bonding processes for repairs to load-bearing members:
gas brazing
soldering
adhesive bonding
fibre reinforcement
body filler
Mig brazing is used to attach low strength cosmetic panels to high strength boron steel without affecting the steels structure, as welding to boron
steel makes it brittle in the heat affected zone.
Bonding and riveting is used to attach both boron steel panels and dissimilar metals together, but uses self piercing punch rivets which are a
completely different strength class to a pop rivet, the adhesive is a secondary attachment in this kind of repair as the boron steel is approx
1500mpa, the structural epoxy is approx 25mpa.
Dave
Again a roll bar being a load bearing member would be interpretation. Mine would load bearing when in normal use, ie suspension, steering, sub fame
mounts etc. An MoT tester cannot assume to be a crash/impact investigator.
It's not an assumption, the attachment point of any subassembly that is load bearing is also a prescribed area; ie a front subframe that carries
suspension components has a 300mm prescribed area at every attachment point where it is bolted to the body, a seat which carries any seatbelt
attachments has the same prescribed areas at its mounting points.
The upper seatbelt bolt goes through the rollbar so it is definately load bearing.
quote:
Out of interest, could the repair seams be put in a better location? For me I don't know whether having a seam at that position introduces a
weakness in the structure. Would it have been better to use more of the donor material and cut away the original until it was in a 'safer'
location?
My personal view ignoring any provenance issues is i would remove the whole extruded section from the donor chassis and the damaged section from the
original chassis, remove the adhesive from the serrated faces that it bonds to (not sure if there is any way of doing this without damaging them),
then use the oe elise s2 dow coring adhesive to attach the replacement extruded section. The adhesive used on the s2 does not require any heat to cure
and has sufficent mechanical properties to replace the original.
That would leave a repair that satisfies the mot, and should be as strong as it left the factory.
quote:Originally posted by Mr Whippy
Am I the only person who thinks that repair looks like crap? Yeah that may be only 5% of the chassis but it's a rather important part. God knows
how that section will behave in a crash and nobody does cos it ain't been tested in any way. I just hope it is not sold on to some unsuspecting
buyer who doesn't realise what's lurking under the bodywork.
Nor has any welding on any steel car and their must be literally 100's of 1000s of cars on the road with mig welded repairs of which a lot would
have had accidents and proved to be fine - or they would ban repairing any rusty chassis.
The tig welding on the inner face looks fine, not exceptionally neat but looks well penetrated IMO. Most glues and epoxies are famed for being
stronger than their parent material, or the Elise wouldnt have become so famed for being glued in the first place. Seems like a lot knees jerking
here.
What would submitting it for an IVA actually achieve? I wasn't aware they asked for structural analysis, even of one offs. If you submitted this
or even a home built bonded monocoque, they'd say yep, it's got all the right e marks, the lights are in the right place, it's not
too sharp and it's not too noisy. Would it be safer once it was approved and age related plated? It was already 'repaired' and back
on the road when he bought it by the sound of it.
I could somewhat understand this question on an Elise forum, but being a forum of home builders of bits of tube stuck together by often very
inexperienced welders, I'd think people in glass houses should be careful what they throw.
Does anyone have a written statement from Lotus to say why it can't be repaired? It might be that they don't want to hold inventory for
chassis spares or it might be that they don't want to take on the liability for condoning uncontrolled application of structural adhesives. In
any case, the statement can't be that repair methods fundamentally don't exist.
quote:Originally posted by obfripper
Mig brazing is used to attach low strength cosmetic panels to high strength boron steel without affecting the steels structure, as welding to boron
steel makes it brittle in the heat affected zone.
Bonding and riveting is used to attach both boron steel panels and dissimilar metals together, but uses self piercing punch rivets which are a
completely different strength class to a pop rivet, the adhesive is a secondary attachment in this kind of repair as the boron steel is approx
1500MPa, the structural epoxy is approx 25MPa.
I get your point, but the adhesive is designed to work in shear, not tension so to be apples to apples, the comparison should include the area of the
lap on the backing plates and use the yield stress of the steel, not the UTS.
quote:Originally posted by John Bonnett
In my view, no because chassis and monocoque repairs are permitted and happen all the time. Where the material for the repair was sourced is
immaterial.
Interestingly my recent accidental excursion into the rear of a VW with my hilux was an eye opener. Naturally it caused a fair old dent to the rear of
the vw, but it also slightly bent my bumper support bracket. That bracket is welded to the chassis rail end. The chassis being 3mm steel, the bracket
1.5mm.
Insurance company wrote that off as unrepairable structural damage as Toyota say ladder chassis repair isn't possible safely. Only when I broke
out the ABI guidance could I convince the company to send an assessor.
Looking at the ABI docs here, this is structural and would certainly need at least an engineers sign off.
I'm not keen on his statement of "better to have too much glue than too little. That's rarely the case.
