Body off chassis repair/replace

Body off chassis repair/replace

Author
Discussion

walt762

Original Poster:

240 posts

232 months

Friday 13th February 2015
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I am looking for some advice guys,
I have removed the body to repair/replace the chassis and the outriggers are in reasonable condition with no holes but there is holes on the main upper rails where the rear of the wishbones meet the rail, hence the body off!
The plates coming up into the rear wheel arches for holding the seatbelts to the chassis are also pretty rusty and could be probably be broken off with little effort.
The car is a Nov 96 500
Should I get the chassis repaired or would it be better to bite the bullet and replace it?
I don't want it powder coated as I bought new upper wishbones 2 years ago and they are already rusting badly, so what coating would be better?
I like the idea of Galvanising it but worried about twisting.






not sure if the pictures will work as it's been a while since I posted any & forgotten how.

ianwayne

6,293 posts

268 months

Friday 13th February 2015
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If you have the facilities to do it all yourself, which by the sound of it you do, these guys do a new chassis for £3k:

http://www.rtracing.co.uk/content/tvr-chassis-rest...

It's an old page so the price may have gone up, and it's not clear if that is a delivered price. A full refurb would cost more than that.

walt762

Original Poster:

240 posts

232 months

Friday 13th February 2015
quotequote all
Thanks, I have have a note of RT Racing & Sportmotive, I will give them a phone once I have more of a plan.

TVRPierre

77 posts

203 months

Friday 13th February 2015
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Southways Automotive might be worth a visit http://www.southwaysautomotive.co.uk/
They have been doing quite a few chassis refurbs. I have seen them and they look really nice.

caduceus

6,071 posts

266 months

Friday 13th February 2015
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It really all depends on budget doesn't it? If you've got money to throw at it regardless, get a new one. But all that you have mentioned is very fixable.

Chuffmeister

3,597 posts

137 months

Saturday 14th February 2015
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There have been several lengthy threads about galvenising and coating a chassis. Here's what I have taken away from them:

1. Hot dip galvenising.

You need to drill holes to allow the gasses to escape during the galvenising process. Some say it weakens the chassis,whilst others don't think it will be an issue. No testing has been done on the impact on the strength of the chassis, so the jury is still out. I'm not convinced that the Chim would offer you much protection in a serious impact anyway.

Warping: Again, some on here have had the hot dip galvanising done succesfully without warping, others had had some minor warping, but straightened on a jig. The key seems to be to find somewhere with experience and reputation to complete the galvenising properly and these avoid issues. You pays your money...

2. Hot spray galvenising and cold painted galvenising: several have had this done successfully and without problems. I hear that the cold galv is more prone to flake under impact, however, protecting it with a decent paint will solve this problem. Zinga seems to be a popular cold galv paint. The key is in the prep and application.

Paints.

By far the best route seems to be 2k epoxy mastic, with a suitable primer that will allow it to bond to the galv. There are many PHers that swear by powder coat, however, I would want something that bonds to my chassis and not coat it. Again, one of those judgement calls.

A new chassis would be awesome, but I can see that it wouldn't all be plain sailing making it fit. By far the cheapest route is to media blast your exisiting chassis, repair and protect.

walt762

Original Poster:

240 posts

232 months

Saturday 14th February 2015
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As you mention above, the big worry with a new chassis would be hoping all the mounting holes line up.
I would be hoping they do but it wouldn't surprise me if some of the holes weren't drilled to place making each one unique.

I really don't want to have to do this again in 5 years time which is why I like the galvanising option and will not be going with powder coating.

I am thinking of laser scanning the chassis then modelling it and getting some Finite Element Analysis done on it but I will need to decide before I get that far unfortunately.

portzi

2,296 posts

175 months

Saturday 14th February 2015
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walt762 said:
As you mention above, the big worry with a new chassis would be hoping all the mounting holes line up.
I would be hoping they do but it wouldn't surprise me if some of the holes weren't drilled to place making each one unique.

I really don't want to have to do this again in 5 years time which is why I like the galvanising option and will not be going with powder coating.

I am thinking of laser scanning the chassis then modelling it and getting some Finite Element Analysis done on it but I will need to decide before I get that far unfortunately.
Keep your original chassis get the sections that are rotten cut out and reweld new sections in. I had a body off full chassis engine rebuild, diff etc . This is 3 years ago now. Had my chassis which was zinc primed and powder coated with expoxy resin covering over the top and it looks mint. Galvanised would have been my first choice though so go galv first!!!!

walt762

Original Poster:

240 posts

232 months

Saturday 14th February 2015
quotequote all
Thanks portzi, I like the idea of epoxy resin it sounds pretty tough and good to hear yours is still in good nick after 3 years.

S7Paul

2,103 posts

234 months

Saturday 14th February 2015
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I would definitely advise repairing your existing chassis. Southways did mine, and had to replace a section of the main chassis rectangular tubing as well as the obligatory outriggers. Once completed, they they had it hot zinc sprayed, which according to the people that do it is good enough protection by itself.

That was followed by the top coat, and like many other people I had the epoxy v powder coat dilemma. I ended up speaking directly to the company that supplies all the raw materials to the company that Southways use for painting, and they were very clear - use powder coat.

I asked about adhesion and what happens if it gets chipped, and they said that modern powder coating, if applied properly over correctly prepared surfaces does adhere to the metal, and the problem of water getting under it and spreading shouldn't happen.


walt762

Original Poster:

240 posts

232 months

Saturday 14th February 2015
quotequote all
I am coming round to fixing the existing one however as I mentioned above i bought new wishbones from a well known dealer and after 2 years the powder coating is flaking off badly which isn't the end of the world as they can be fairly easily sorted however I want the chassis to last a long time.
what I was doing today.


note; - the gaps in the chassis are not holes I struggled to get it to scan these areas and since it is a straight piece of tube I wasn't bothered.

S7Paul

2,103 posts

234 months

Saturday 14th February 2015
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If it's flaking off after 2 years, either it isn't powder coat (just ordinary paint) or it's been done very badly.

walt762

Original Poster:

240 posts

232 months

Saturday 14th February 2015
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Looks powder coated to me, was very smooth but whatever it is it didn't last nearly long enough.

TJC46

2,148 posts

206 months

Sunday 15th February 2015
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walt762 said:
Thanks, I have have a note of RT Racing & Sportmotive, I will give them a phone once I have more of a plan.
Either one will do a first class job, but looking in detail at your pics, the first thing to do is to have it shot-blasted.

As you say the outriggers etc look ok, but once blasted i think you may find quite a horror story.

Speak with Richard at RT, or Ian at sport-motive i'm sure they will both want to blast it first, then discuss with yourself if it can be repaired, or if its better to fit a new chassis.

Good luck

tom.

portzi

2,296 posts

175 months

Sunday 15th February 2015
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walt762 said:
I am coming round to fixing the existing one however as I mentioned above i bought new wishbones from a well known dealer and after 2 years the powder coating is flaking off badly which isn't the end of the world as they can be fairly easily sorted however I want the chassis to last a long time.
what I was doing today.


note; - the gaps in the chassis are not holes I struggled to get it to scan these areas and since it is a straight piece of tube I wasn't bothered.
Walt, are you using a faro arm laser scanner on your chassis? I upgraded to tubular wishbones, the lowers were bought from St8 six and are spotless so very happy smile

walt762

Original Poster:

240 posts

232 months

Sunday 15th February 2015
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It was a Creaform Exascan portable laser scanner I used.
I am hoping to model the chassis when I get back to work but that may take a bit of time as work comes first.
I am only planning on replacing the front lower wishbones & getting the rest blasted but the rears may need replaced I will see when they are cleaned up.

scotty_d

6,795 posts

194 months

Wednesday 18th February 2015
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A few pictures from today's progress hope you don't mind Walter.









walt762

Original Poster:

240 posts

232 months

Wednesday 18th February 2015
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Cheers Scott, pity I feature in them but certainly a good bit done in an afternoon.

Thanks again for the help.

scotty_d

6,795 posts

194 months

Wednesday 18th February 2015
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Can remove those ones if you want?

walt762

Original Poster:

240 posts

232 months

Wednesday 18th February 2015
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Haha, I think I can live with the "fame"