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K3 body/tub reinforcement
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Author:  tonygerrard(1049) [ Thu Feb 21, 2019 7:51 pm ]
Post subject:  K3 body/tub reinforcement

Hi, have acquired a K3 but body is damaged, not broken, and could be repaired.
I read on Facebook Bob Morrison : "I pumped up the n/s rear and o/s tyres today with the hard-top locked in above the windscreen and watched the gap grow between body and rear of hard-top - I've seen the gap bigger than this at some point in the past which is why I ask about shell stiffening." & "So - when we first got the car, it was great while cornering, accelerating and decelerating but was very strange in a straight line - it sort of squirmed are the rear and you always felt the need to correct it - or you felt like it was just going to let go and spin!" And Dudley was a little disparaging about the absence of a continuation of the gear change tunnel into the front floor.
Whilst I've got it in pieces I might as well strengthen it whilst trying not to make it weigh more.
Does anyone have a drawing of the structure that I could have or pictures of the build?
Does the tub contain boxes (in fibreglass like the later Libra?) or is it just a rudimentary tub but with a foam filled arch under the dashboard?
If anyone can help, I'd be grateful.
Cheers,
Tony.

Author:  techead [ Thu Feb 21, 2019 11:08 pm ]
Post subject:  Re: K3 body/tub reinforcement

Not sure what you are looking for. I do have a tub completely stripped and could photograph anything you are looking for. All you need is a list for me to work through.

Author:  Howardy [ Thu Feb 21, 2019 11:30 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hello, My only experience of a similar condition when I had a K3 was on a motorway or dual carraigeway where the lorries had left two grooves it used to wander to the point of have to slow down. Check the rear steering links on the back suspension the standard ones have track rod ends at the outer ends and rubber bushed inner joints. I replaced the inner joints with rose joints which completely cured the problem. The other bushes to check are the subframe to body joints at the back of the front subframe and the front of the rear subframe. I had all these welded up across the bushes to stop any movement. All the best Howard

Author:  tonygerrard(1049) [ Fri Feb 22, 2019 12:26 am ]
Post subject:  Re: K3 body/tub reinforcement

Techead,
I'd be very interested in photos of the arch that spans the sill at the front where it touches the body & dashboard and the shelf that carries to petrol tank. Is there a box underneath, as part of the body.
Or where are you and could I come and have a look with camera?
Advice from Howardy is valuable too.
Thanks both,
Tony.

Author:  sanzomat [ Fri Feb 22, 2019 8:37 am ]
Post subject:  Re: K3 body/tub reinforcement

Sorry to butt in, in typical forum fashion knowing nothing about K3's! From the description of wandering in straight line but being fine in corners it suggests to me that geometry issues are more likely to be the cause rather than lack of stiffness, albeit a flexing tub would alter the geometry too. Things like toe-in, front and rear, can have a big impact on straight line stability and of course if there is any wear or slack in any of the suspension components then strange things will happen too, often not noticed during cornering as once the slack is taken up the loads hold it in place. Also worth checking how much bump steer is present.

Author:  tonygerrard(1049) [ Fri Feb 22, 2019 10:13 am ]
Post subject:  Re: K3 body/tub reinforcement

thanks sanzomat,
It looks like a stiffer body, coupled with correct geometry and new bushes would result in the best handling for the car. And you're not butting in, I'm grateful for your contribution.
Cheers,
Tony.

Author:  techead [ Fri Feb 22, 2019 3:24 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hope these photos are what you are looking for.

The previous owner cut some of the dash support away, the main strength beam can be seen intact.
I am in Erskine just outside of Glasgow.
If you need some other shots just let me know.

Attachments:
back of body tub.jpg
back of body tub.jpg [ 538 KiB | Viewed 7755 times ]
back of body from inside.jpg
back of body from inside.jpg [ 516.99 KiB | Viewed 7755 times ]
dashboard support.jpg
dashboard support.jpg [ 522.97 KiB | Viewed 7755 times ]
dashboard 2.jpg
dashboard 2.jpg [ 556.44 KiB | Viewed 7755 times ]

Author:  tonygerrard(1049) [ Sun Feb 24, 2019 11:31 pm ]
Post subject:  Re: K3 body/tub reinforcement

techead,
Those photos are SUPERB and just what I needed. I should be able to increase the structural rigidity before adding subframes and better rear links.
The only other pics I need are one of the underside of the tub and one more directly into the rear, to show the inside of the rear where the subframe tubes triangulate to the body.
Wolverhampton is a 10hr round trip with no breaks so thank you for the information.
Cheers,
Tony.
Oh yes, I could do with some tuition in picture loading too.

Author:  techead [ Mon Feb 25, 2019 5:02 pm ]
Post subject:  Re: K3 body/tub reinforcement

Tony
Here are the photos you asked for. I am not well enough just now to turn the tub over, the underside is completely flat apart from the central tunnel that the water pipes run in.
Posting photos.
Save your photos as jpegs setting the size to 640x480, this makes the files a lot smaller in memory size and still keeps them usable for the net.
You can then attach them to your postings using the upload attachment section.
I have just been re reading your post and now realise you have a damaged shell. I may have a solution for you. I got my k3 to use in a school with pupils doing the build. I unfortunately took unwell 2 years ago and now have a diagnosed heart condition. I am not likely to complete the rebuild of the car and have not been driving for the past few years. I did an oil change on my own car yesterday, it should have taken 40minutes I took 2.5hrs. I would not have minded if I had hit a problem but I didn't.

Anyway last night was the final straw I decided that the kit had to go. If you are interested you can have all of the bits to build a complete car for £300. At that price it would be a viable project to put back on the road and still be able to get your money back. Or take the lot and just use the body tub to fix your car.

I have a good soft top, hard top, body tub and doors, doors have electric windows ect. There are a lot of other things worth looking at.

The car is a great base for a rebuild. The body has a terrible paint job all blisters but no cracks or chips, The mechanicals need the usual clean and paint.

Attachments:
rear subframe top mount.jpg
rear subframe top mount.jpg [ 104.09 KiB | Viewed 7658 times ]
rear subframe top mount 2.jpg
rear subframe top mount 2.jpg [ 85.3 KiB | Viewed 7658 times ]
rear subframe mount from inside 2.jpg
rear subframe mount from inside 2.jpg [ 82.18 KiB | Viewed 7658 times ]
rear subframe mount from inside.jpg
rear subframe mount from inside.jpg [ 76.18 KiB | Viewed 7658 times ]

Author:  tonygerrard(1049) [ Mon Feb 25, 2019 11:56 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hi Techead,
I'm sorry to hear about your health.
I wish you'd said about the K3 about 6 weeks ago, but I'd bought one from Lampeter in Wales and rented another garage to store it. I now have 3 garages containing Lancia Fulvia Zagato Sport 1.3, Lancia Fulvia coupe 1.3 and GTM K3, I also have a GTM Coupe on the drive. All requiring work. Panel beating course next month!!
The reason I needed pics is that I'm going to remake the tub in either triaxial glass or carbon fibre using resin infusion with epoxy resin and I might reinforce the floor/sills to help with the body flex.
I can't rent another garage - "Her indoors" would kill me. But if I move the K3 across I might get another tub in (on a mattress)with doors and a soft top.
We are away this weekend but I'll do some measuring up and get back to you and also get transport costs form Erskine. Would it all fit in a LWB transit?
Thanks for the other pics too - very helpful.
The damage on mine is restricted to the rear corner of the tub, just below where the rear clam closes to the tub and the windscreen.
BTW do you have V5 and old MOT docs?
I might also run to other components but maybe not engine and box.
Cheers,
Tony Gerrard.

Author:  techead [ Tue Feb 26, 2019 10:05 am ]
Post subject:  Re: K3 body/tub reinforcement

I moved the whole lot in a luton box van with a tail lift, it went in with a little bit of space left over.
I have the paperwork for the car, I think I may have old mot`s but I would need to look long and hard to find them. I think you can look up the old mot`s on line using the registration number.

It sounds like you are at the start of an interesting project. I started mine as a way of preparing pupils for moving into automotive trades. The school I work at is next to a big motor retail park and I have good links for apprentice places. I had previously built a 3 wheeler BRA cv3 with a group of over 50 pupils, a lot went on to get apprenticeship places from the project.

When I took ill my son who at the time was doing a motor sport degree and working at the touring car championship, suggested reworking the kit to take a different power plant and also make it lighter. He did a fair amount of work on the project and came to the conclusion that there is a lot of weight loss to be gained in getting rid of the subframes. He also thought that a change to electric propulsion would be interesting. You can look up my other posts on that subject.

Most of the shape at the back of the tub is only there to accommodate the fuel tank, so that area could be simplified. You could also gain a bit more strength to the tub and floor area by adding a centre tunnel between the seats running up under the dashboard and joining onto the cross beam. You now have created a backbone chassis sort of set up. When you also take the box sills and cross beams into the equation you have a very rigid body tub.

As you add strength you can reduce layup strength a little which helps keep weight down you may even end up lighter. Carbon fibre looks great but has a lot of build problems, its very brittle, any flaw in the layup ruins the strength advantage and its harder to add things on to at a later date. A well specked grp system would be a better solution for a one off project. There are many different mats and core materials which can be used to create very stiff panels.

Author:  tonygerrard(1049) [ Tue Feb 26, 2019 7:42 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hi Techead,
I thought you were a teacher.
Carbon also has the disadvantage of reacting with the iron in bolts and the triaxial Glass is cheaper too. I've been looking to use S glass but it's only available in light (190 gm2) I've got a couple of meters of carbon, triaxial and S glass and will do a trial before I start. Was going to make a complete tub for the Coupe but then I'd have to IVA it and the nearest station is Bristol, I think, and it's a lot of hassle.
Yes, Dudley suggested I do the tunnel to the front and I might do some embossing in floor, the box at the rear and some bracing between central tunnel and sills.
I plan to use vacuum and in doing so I should end up with similar (but no voids) thickness but with about o.6 weight of resin instead of the x 2ish typical of hand layup, so there is some saving but I like the rear end and Its convoluted shape might add some strength.
A Luton Box stands a chance and I'll look into that and I'll look for Mot too.

Thanks,
Tony Gerrard

Author:  tonygerrard(1049) [ Tue Feb 26, 2019 7:49 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hi Techead again,
One more thing I'd been thinking about was the inclusion of some Innegra along with the Carbon.
https://www.youtube.com/watch?v=0N-LiWRA7RQ

Tony Gerrard

Author:  techead [ Tue Feb 26, 2019 9:00 pm ]
Post subject:  Re: K3 body/tub reinforcement

If you strengthen the body tub you can then treat the front and rear suspension systems like those in the early lotus elan. It has a cross member bolted to the front of the chassis and the rear box of the centre back bone extends out to take suspension and engine. This would save you a lot of weight, allow you to use almost any suspension components you wanted along with any wheel of choice.

Composites are wonderful materials and by using different cloths and lay ups you can gain a wide range of strength or flex, or anything in between. I liked the video and had seen a similar thing using a nylon based woven cloth. You need to remember that you need the load points to be ridged and fixed to keep the geometry of the rest of the car from moving when under way.

Your project sounds great and I look forward to seeing it develop.

Author:  tonygerrard(1049) [ Wed Feb 27, 2019 12:29 pm ]
Post subject:  Re: K3 body/tub reinforcement

Hi Techead,
I think you mean the Europa but the chassis are very similar, just A over T or are they the same (essentially)?
If I was to modify the suspension and engine frame I think I'd be on the the same lines as the Libra, but to keep it simple I think I'll just stick to the subframes a la Metro/TF. I'm nearly 70 so I haven't got too much time to muck about.
Does anyone know where the original K3 moulds are?

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