MK chippy
|
| posted on 28/5/14 at 11:44 AM |
|
|
Have you spoken to mnr? Just wondered what their advice would be to get over this?
Dave
|
|
|
|
|
Mr Whippy
|
| posted on 28/5/14 at 12:02 PM |
|
|
Would have been better if the bracket wrapped around the tube rather than just welded onto the face or the tubes where the suspension was mounted were
thicker than the rest, or both
My nissan has thin wall tubes like that for its trailing arms at the rear, which are just fine so long as the bushes on the ends are free to turn, the
second the bushes start to seize….SNAP! 
|
|
|
loggyboy
|
| posted on 28/5/14 at 12:21 PM |
|
|
quote:
Originally posted by designer
quote:
The last one had a habit of breaking rear wishbone mounts where the bracket had been welded to a round tube!
There would seem to be a design problem!
How knee jerk - considering the MNR chassis has been around for quite a few years and this is a one off (as far as we know) how can you assume its a
design problem.
Unless any more cars come forward with same issue its more likely to be an isolated, quality of material or construction issue.
Mistral Motorsport
|
|
|
gaz_gaz
|
| posted on 28/5/14 at 12:27 PM |
|
|
quote:
Originally posted by MK chippy
Have you spoken to mnr? Just wondered what their advice would braced ul over this?
Dave
I've made MNR aware of the issue amd they've said they need the car back at the factory. the problem I have is that is a 500 mile round
trip plus repair costs on top so I'm tempted to take a very kind offer up made by a local forum member and have it fixed locally.
Early possible causes are according to them are.
incorrect toe or camber
incorrect corner weights.
seized rose joint
previous accident damage unnoticed.
What isn't a cause according to them is
Tube thickness
welding quality
bracket location
Despite the car being a 2008 registered car, Chris believes the car was a 2004 build, inboard suspension car that was raced before being registered in
2008
This is different to the information given to me when I bought the car so I'm waiting to hear back from the original first registered keeper.
He's in meetings but has promised to call me back.
[Edited on 28/5/14 by gaz_gaz]
[Edited on 28/5/14 by gaz_gaz]
|
|
|
designer
|
| posted on 28/5/14 at 02:18 PM |
|
|
I remember that another Locoster had the same problem a couple of years ago.
It's irrelevant what year the chassis is; it broke!!
|
|
|
sdh2903
|
| posted on 28/5/14 at 02:58 PM |
|
|
I'm quite shocked at just how thin the material at such a load bearing part of the chassis.
As someone who has never constructed a chassis, is that the normal gauge material to be using? Is that what all the more well known kit manufacturers
are using?
|
|
|
MK chippy
|
| posted on 28/5/14 at 03:06 PM |
|
|
Luckily no one was hurt you were on a track day and it didn't happen on a road with no run off etc.
Dave
|
|
|
britishtrident
|
| posted on 28/5/14 at 03:43 PM |
|
|
quote:
Originally posted by sdh2903
I'm quite shocked at just how thin the material at such a load bearing part of the chassis.
As someone who has never constructed a chassis, is that the normal gauge material to be using? Is that what all the more well known kit manufacturers
are using?
Most racing car spaceframes including Lotus Sevens were traditionally made from 18 gauge "Reynolds" tube and had brazed joints ( the
modern equivalent is T45) it worked fine but broken tubes were not unknown particularly on Chapmans chassis which were so sparse they looked like
wire coat hangers and didn't weigh much more.
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
procomp
|
| posted on 28/5/14 at 04:28 PM |
|
|
Far from being a first and a one off.
Howmany have had the rear brkts fall off 3-4 and this is what the 2nd - 3rd where the front brackets / chassis have given way. !!!
|
|
|
Doctor Derek Doctors
|
| posted on 28/5/14 at 07:52 PM |
|
|
quote:
Early possible causes are according to them are.
incorrect toe or camber
incorrect corner weights.
seized rose joint
previous accident damage unnoticed.
What isn't a cause according to them is
Tube thickness
welding quality
bracket location
Did they genuinely say that? If so that's absolutely ridiculous, it would be hilarious if it wasn't so dangerous.
Designer and Supplier of the T89 Designs - Single Seater Locost. Build you own Single Seater Racecar for ~£5k.
Plans and Drawings available, U2U or e-mail for details.
Available Now: The Sports Racer Add-On pack, Build a full bodied Sports Racer for Trackdays, Sprints and Racing.
www.t89.co.uk
www.racecarwings.co.uk
callan@t89.co.uk
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
gaz_gaz
|
| posted on 28/5/14 at 08:12 PM |
|
|
Unfortunately yes.
|
|
|
Alfa145
|
| posted on 28/5/14 at 08:17 PM |
|
|
So, running a certain degree of Toe or camber might cause a suspension bracket to rip off?
What are the limits? 2deg? 10deg? 45deg? 180deg?
Same goes for corner weights.... if the car is so sensitive to such small changes then it isn't safe on the road.
Never heard anything so pathetic.....
Although to be fair the other options, seized rose joint and previous accident damage unnoticed, are certainly more probable
[Edited on 28/5/14 by Alfa145]
|
|
|
micksalt
|
| posted on 29/5/14 at 07:35 AM |
|
|
Looking at the photos of the chassis on the MNR website, it appears that this type of bracket is no longer used at the front. It looks like it might
still be in use to the rear though, so it would be good to hear the official word from Marc or Chris on this particular matter.
|
|
|
marc n
|
| posted on 29/5/14 at 09:48 AM |
|
|
Hi all just to state a few facts:-
We have been in contact with the current owner to try and ascertain what has happened,
obviously it is easier to diagnose seeing the car rather than just a couple of pictures:-
However rather than jump to a conclusion all facts have to be examined, and possible causes investigated
So we asked the following:-
copied and pasted email below
-------- Original message --------
From: Chris Nordon
Date:27/05/2014 20:00 (GMT+00:00)
To: "Gaz ."
Subject: Re: MNR Broken suspension
Hi Gary
What settings did you use-ie camber and toe?
Rgds
Chris
Please note this was a question asked to ascertain the facts
and not as a member on here has suggested stated as a reason for failure,
however incorrect setup can be a possibly contributory reason for failure.
This is to make sure the car is running correct geometry as this is a fully rose-jointed car
and if the cambers / toe / ride-heights are excessive then rod-end lockout is a possibility.
The car in question is an early race-car / track-day car which is a circa 2004
car despite the car showing an 08 plate.
As the car is a race-car it has a mix of tubing 1 inch, 3/4 inch od with varying wall thicknesses throughout, 16 and 18 gauge
and is subject to the usual tolerances of tube manufacture:- wall thickness tolerance of -10 % and anything up to + 18%
and outside diameter tolerance of -0.4mm to plus 0.8mm
As far as we are aware and can remember we have not seen this car since 2008
( please bear in mind we are a medium sized manufacturer so produce up to 100 cars a year ) so can only recall histories of cars
if we have documented correspondence / have a history of supplying parts.
we don't have a great deal of notes about this particular car so cannot be sure if the car has had any maintenance history,
or even give any history regarding possible accidents / usage. This is not uncommon with a car of this age, as some cars just
disappear off the radar completely or are on the 6th plus owner / have been maintained or have been fixed elsewhere
And in some cases there are cars that loose their identity by being exported or re imported.
So far we have been asked to identify why it has broken based on 2 photos and being told it has been at anglesy race track
this is the only information since 2008.
So based on that information all we can do is ask for as much information as possible,
ultimately we need to inspect the car
It could well be that all the rod-ends are nearly 10 years old and have an element of wear and play depending on usage
or even it has been involved in an accident and has been fixed by a previous owner / user or even a third party garage,
( as the current owner is now considering )
The current owner has confirmed that the setup is in the ballpark of a std car - have previous owners been as prudent in checking ???
we simply do not know.
All i can comment on is 2 pictures, and all i can glean from those is one shows a loose rod-end lock-nut,
which will allow a twisting force under heavy braking, is this maybe an indication of a lack of previous maintenance??
Also it appears that the suspension bracket is pinched in and the sides are not at 90 degrees - so indicates that there could be
incorrect spacing, which would create stress on the bracket.
Having spoken to the current owner it would appear that there is a washer behind the rod-end lock-nut which indicates
this wishbone has been removed at some point ( as there is no washer fitted to that location ever )
The wishbone appears to have been removed and then been incorrectly refitted or even replaced ??, this could be for a variety of reasons:-
1. To re-powdercoat wishbone due to stone chips etc
2. A worn rod-end has been replaced
3. A new suspension arm has been fitted due to damage
Comments regarding previous failures should be considered on their own merit and supported by facts of individual cases and
not hearsay. As an example about 5 years ago :- we had a customer who alleged a bracket had failed whilst on a track-day.
Yes it did...... after he had made heavy contact with a barrier which a YouTube clip found on the internet substantiated.
I am not in anyway suggesting this is the case with the current owner before anyone comments that is the case,
the fact that sometimes people don't always give the full picture and just an edited version of events.
how many times have you seen the fabled words low mileage and one careful owner on an advert for a used car
( not just kit-cars but all cars ) and they turn out to have a hidden history.
Without an inspection of the car these are the only conclusions we can make on evidence provided
We have asked the owner to bring the car to us for inspection and a full health check,
so we can get some answers rather than speculate.
Once we have done this i will happily update this thread with findings and the outcome,
however i will not get involved in a debate, with other manufacturers or anyone else for that matter based on
2 pictures and hearsay or not knowing the full facts.
Best regards
Marc
please email rather than u2u
direct workshop email ( manned 8am till 6pm )
www.mnrltd.co.uk enquireys to :-
chrismnrltd@btinternet.com
|
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
|
CNHSS1
|
| posted on 29/5/14 at 10:02 AM |
|
|
that seems an extremely fair and accurate statement from Marc imho. Any racer chassis that's lasted 10 seasons is doing well given the
'ammer they get!
cars used 'hard' on the road suffer far less than a race car, irrespective of what owners think. Generally racers use stickier tyres, and
the cars loaded to the max in a corner amd then you take a big chunk of curb to get the times, amazing the bloody things hang together as long as they
do.
a friend races Caterhams and they 'life' the chassis's, irrespective of damage, either whole cars sold on or a fresh chassis fitted
over the winter.
all my opinions of course and no allegiance to any 7type manufacturer, just a happy club hillclimber that batters the sh*t out of everything owned lol
"Racing is life, everything else, before or after, is just waiting"---Steve McQueen
|
|
|
Mr Whippy
|
| posted on 29/5/14 at 11:59 AM |
|
|
it would be worth getting the other suspension point welds dye penetrant checked for cracks just for piece on mind and some new rose joints
|
|
|
Irony
|
| posted on 29/5/14 at 12:51 PM |
|
|
Seems to be a fair comment from MNR. You never know where a secondhand car has been before you buy. I know a fella who bought a Anniversary Edition
Golf MK4 GTI. It had about 50K on the clock. Coppers turned up one day and told him his car had had the clocks altered and in reality it had 254K on
clock!
That MNR could have seen some heavy racing.
|
|
|
CNHSS1
|
| posted on 29/5/14 at 12:53 PM |
|
|
im not sure how the dye penetrant works with powedercoating or paint finishes, most single seater wishbones are passivated or chemically blackened in
some form, so works well on those, maybe Marc or an engineering type has a view?
as for rosejoints, unless changed in last 12 months, change the lot and keep as emergency spares or better still, sling 'em. anything less and a
repeat performance is quite likely imho
if no bills from PO, then change them. Beware of cheap rosejoints too, there load ratings and liner type may not be suitable for all areas on the car
"Racing is life, everything else, before or after, is just waiting"---Steve McQueen
|
|
|
gaz_gaz
|
| posted on 29/5/14 at 01:38 PM |
|
|
I've spoken with Marc today and cleared up a couple of misunderstandings..
My intention was never to rubbish MNR or there product with this thread.
I only wanted an opinion from knowledgeable people.
I do feel it's worth mentioning that the chassis wasn't raced for 10 years solid.
It was raced but how much is unknown and used for trackdays and shows such as kitcar live at Brands Hatch from 2004 to 2008
What I do know is that it's never been raced since 2008 but has done a few trackdays although no previous owner has admitted to knocking the
car!
We are working towards a solution and will hopefully get to the bottom of this failure soon!
|
|
|
micksalt
|
| posted on 17/6/14 at 02:46 PM |
|
|
Did you ever get to the bottom of this?
|
|
|
