Ally corrosion
Discussion
My car has some corrosion issues with the ally skin/ steel chassis reacting with each other, (see pictures).
It's mainly the bottom rail running alongside the passenger side of the car. But also on the drivers bottom rail, the drivers top rail around the scuttle also and the same on the passenger side. The exhaust was off when I took these photos.
IT's a 1999 car which has slight issues when bought ~4.5 years ago, but has lived outside for most of the time since and this obviously hasn't helped!
Cosmetic wise, I'm not overly fussed. It's shabby, but used as opposed to merely out of the garage.
Skip forward 2 years for now and I'll hopefully be living in Oz and a year after that, I'd like to (if all is going well), import the car to Oz.
So with the car being very much British, I'm thinking of getting some work done on it while it's on UK soil.
I'm tempted by a bit more DVA engine work, but is this a problem which ideally needs sorting, and now?
It'll be a new panel job I'm sure. Both sides, which I'm sure costs quite a bit. And once the panels are off, who says I won't end up wanting to strip the whole lot and re-powder coating the chassis, then having to paint it all once back together. I can see the bills stacking up already.
So...what are peoples views on how bad that corrosion is? It's a 1999 car with 40K plus on the clock.
Has anyone previous experiences of the costs involved in a repanel? A respray? A strip and fresh coating on the chassis?
The hole is where the original exhaust had a second mount.
It's mainly the bottom rail running alongside the passenger side of the car. But also on the drivers bottom rail, the drivers top rail around the scuttle also and the same on the passenger side. The exhaust was off when I took these photos.
IT's a 1999 car which has slight issues when bought ~4.5 years ago, but has lived outside for most of the time since and this obviously hasn't helped!
Cosmetic wise, I'm not overly fussed. It's shabby, but used as opposed to merely out of the garage.
Skip forward 2 years for now and I'll hopefully be living in Oz and a year after that, I'd like to (if all is going well), import the car to Oz.
So with the car being very much British, I'm thinking of getting some work done on it while it's on UK soil.
I'm tempted by a bit more DVA engine work, but is this a problem which ideally needs sorting, and now?
It'll be a new panel job I'm sure. Both sides, which I'm sure costs quite a bit. And once the panels are off, who says I won't end up wanting to strip the whole lot and re-powder coating the chassis, then having to paint it all once back together. I can see the bills stacking up already.
So...what are peoples views on how bad that corrosion is? It's a 1999 car with 40K plus on the clock.
Has anyone previous experiences of the costs involved in a repanel? A respray? A strip and fresh coating on the chassis?
The hole is where the original exhaust had a second mount.
You mean something like this http://www.youtube.com/watch?v=olfz079ZrG4
You may want to contact Angus & Tessa and have a chat for their experience
http://www.mycaterham.com
You may want to contact Angus & Tessa and have a chat for their experience
http://www.mycaterham.com
I can't answer your question but can give some advice to putting it back together.
I have to say this is a problem that could be avoided or prolonged. I don't think this is great after so few years, the corrosion would have been bubbling and looked tatty quite a few years earlier but more of a concern is that the panels are a structural part to some extent! The mid 90's chassis also have a poor reputation for corrosion from what I have read.
Electrolysis between steel and ali has been Land Rovers bug bear for many years, finally with the later TDCi's they are using ali on ali where they can and are treating the doors for instance with some kind of wax treatment from new. They redesigned the back door so that water wouldn't just poor in which has helped a lot.
When re-skinning Land Rover doors on rebuilds, rather than relying on stuff like Duralac to provide a barrier between the two metals, permanent flexible skins are used - people use anything from cut up fertiliser bags to builders liner used underneath floors etc - anything that is flexible but strong! A good layer of paint/Dinitrol etc is then used to prevent water/moisture getting any where near it.
The other consideration are the rivets themselves. These need to be ali rivets of course (don't know what Caterham use) and they need to be seated with something like Duralace again to stop moisture getting anywhere especially between the rivet and steel chassis. Better again to sheath the rivet in something sturdier rather than rely on a paste which will largely just get squeezed out - again people use various methods but heating a bit of plastic over the rivets so it shrinks over it is another idea. This method is also used on yacht masts - same problem, ali mast with steel fixings/fasteners especially rivets and especially because of the marine damp/salty environment.
You can also get water leaks in through a rivet, painted or not. The Land Rover water ingress guide advises you to seal the rivets! Not so bad in a Land Rover you just get a wet floor but in a Caterham you could get water inside the chassis sections - YIKES. I'm guessing with Caterham though, depends on what type of rivet they use. Land Rover use ali rivets with steel pin centers so eventually that steel pin will rot and hey presto more leaks.
It's a damn shame you can't get the chassis delivered to you from new without the panels fitted like some other kits so that you could give the inner tubes of the chassis a squirt of cavity wax and put the skins on with a membrane in between the two surfaces and similarly with each rivet finally plastering the areas with paint/Dinitrol etc that will act as a mud trap. Have to say I am tempted to take a few rivets out, maybe all after research, hand paint the chassis with POR-15 after treating internally as mine will be delivered in bare ali as I am getting it sprayed locally (maybe just bonnet/scuttle and nose cone).
I am hoping to keep mine for years/life so it's worth going the extra mile and I enjoy all that anal stuff, er you know what I mean
I have to say this is a problem that could be avoided or prolonged. I don't think this is great after so few years, the corrosion would have been bubbling and looked tatty quite a few years earlier but more of a concern is that the panels are a structural part to some extent! The mid 90's chassis also have a poor reputation for corrosion from what I have read.
Electrolysis between steel and ali has been Land Rovers bug bear for many years, finally with the later TDCi's they are using ali on ali where they can and are treating the doors for instance with some kind of wax treatment from new. They redesigned the back door so that water wouldn't just poor in which has helped a lot.
When re-skinning Land Rover doors on rebuilds, rather than relying on stuff like Duralac to provide a barrier between the two metals, permanent flexible skins are used - people use anything from cut up fertiliser bags to builders liner used underneath floors etc - anything that is flexible but strong! A good layer of paint/Dinitrol etc is then used to prevent water/moisture getting any where near it.
The other consideration are the rivets themselves. These need to be ali rivets of course (don't know what Caterham use) and they need to be seated with something like Duralace again to stop moisture getting anywhere especially between the rivet and steel chassis. Better again to sheath the rivet in something sturdier rather than rely on a paste which will largely just get squeezed out - again people use various methods but heating a bit of plastic over the rivets so it shrinks over it is another idea. This method is also used on yacht masts - same problem, ali mast with steel fixings/fasteners especially rivets and especially because of the marine damp/salty environment.
You can also get water leaks in through a rivet, painted or not. The Land Rover water ingress guide advises you to seal the rivets! Not so bad in a Land Rover you just get a wet floor but in a Caterham you could get water inside the chassis sections - YIKES. I'm guessing with Caterham though, depends on what type of rivet they use. Land Rover use ali rivets with steel pin centers so eventually that steel pin will rot and hey presto more leaks.
It's a damn shame you can't get the chassis delivered to you from new without the panels fitted like some other kits so that you could give the inner tubes of the chassis a squirt of cavity wax and put the skins on with a membrane in between the two surfaces and similarly with each rivet finally plastering the areas with paint/Dinitrol etc that will act as a mud trap. Have to say I am tempted to take a few rivets out, maybe all after research, hand paint the chassis with POR-15 after treating internally as mine will be delivered in bare ali as I am getting it sprayed locally (maybe just bonnet/scuttle and nose cone).
I am hoping to keep mine for years/life so it's worth going the extra mile and I enjoy all that anal stuff, er you know what I mean
Edited by Zagster on Sunday 19th May 08:44
Send it back to Arch. IIRC from other threads, new powder coating and re-skin is about 2k. Obviously it depends on the amount of tubes that need replacing, but I think that´s ballpark.
You could save some cash and about 2.5kg by not painting it
Zagster, we don´t use Duralac any more. Tef Gel is the product of choice nowadays
It works.
http://tefgel.com/#
You could save some cash and about 2.5kg by not painting it
Zagster, we don´t use Duralac any more. Tef Gel is the product of choice nowadays
It works.http://tefgel.com/#
Thanks for that I couldn't remember the name of the new stuff people use. It's better than Duralac apparently, one of the flaws with Duralac is that it actually attracts moisture.. er not so good then. I have always used permanent liners/barriers...
Edited by Zagster on Sunday 19th May 09:04
Right, so if needs must, I should try to re-panel it myself so I can carry out a better longer lasting job of sorting the ally corrosion issue.
Is this an easy possibility? Apart from an air riveter, would I need any special tools? I guess that I can get the panels direct from Caterham.
Anyone had the their's resprayed to offer a ballpark figure?
Is this an easy possibility? Apart from an air riveter, would I need any special tools? I guess that I can get the panels direct from Caterham.
Anyone had the their's resprayed to offer a ballpark figure?
I stripped my car about 9 years ago and sent the chassis back to Arch. They removed all the panels, blasted the chassis to remove all the old powder coat/rust, replaced a couple of tubes and then zinc phosphate primed it before powder coating and re-paneling. They delivered it to TSK for painting and TSK returned it to me. All in that came to less than £3k.
9 year later the chassis is in good condition and the only place I have had an issue with corrosion is the scuttle where the retaining channels (steel) rusted and caused some localised bubbling - a new scuttle and retaining channels has solved that.
I wouldn't have the patience to re-panel the car myself - you need an air riveter or electric rivet gun and the rear panel is a very skilled job to get looking right around the boot edge. As above there is also a weld required each side to join the back panel to the side panels.
9 year later the chassis is in good condition and the only place I have had an issue with corrosion is the scuttle where the retaining channels (steel) rusted and caused some localised bubbling - a new scuttle and retaining channels has solved that.
I wouldn't have the patience to re-panel the car myself - you need an air riveter or electric rivet gun and the rear panel is a very skilled job to get looking right around the boot edge. As above there is also a weld required each side to join the back panel to the side panels.
There are three welds each side. One above the rear shock turret, a diagonal one at the rear of the cockpit sill. and one under the rear of the lower wishbone mount.
Definitely not a do it at home job, unless you are skilled with TIG and you are a good panel beater. Take it to Arch, or if you want a dogs watsits job, take it to Geoff Moss http://www.mphmotorpanels.com/
Definitely not a do it at home job, unless you are skilled with TIG and you are a good panel beater. Take it to Arch, or if you want a dogs watsits job, take it to Geoff Moss http://www.mphmotorpanels.com/
I only wondered about doing myself, or similar, purely for doing the best 'stay away corrosion' job as opposed to powder coating and then re skinning, which will leave me back to square one.
Shaun, do you know if the chassis is zinc phosphate primed and then powder coated happen when the are first built, or is this a better finish than original?
3K for a full repanel and paint doesn't seem too bad.
Just need to find somewhere to strip it all down really!
Shaun, do you know if the chassis is zinc phosphate primed and then powder coated happen when the are first built, or is this a better finish than original?
3K for a full repanel and paint doesn't seem too bad.
Just need to find somewhere to strip it all down really!
The zinc phosphate priming was introduced later so yes it is better than your original finish. I understand that it stops rust "creeping" should the powder coat be damaged anywhere. On my chassis the rust had crept under the powder coat and it came off in large flakes even though superficially it looked OK.
If he's shipping out a better product now than when Caterham had them commissioned, then brilliant.
I could probably de-panel it if it saved cost, this'll be eating into my Oz fund!
So get it back painted, then go mad with the preservation sprays and what not. Rebuild and be happy.
Thinking Kwackers green, maybe with a stripe or two, not sure yet. My pleasing on the eye Blue with silver stripe will be a thing of the pass.
I could probably de-panel it if it saved cost, this'll be eating into my Oz fund!
So get it back painted, then go mad with the preservation sprays and what not. Rebuild and be happy.
Thinking Kwackers green, maybe with a stripe or two, not sure yet. My pleasing on the eye Blue with silver stripe will be a thing of the pass.
GM,
I, too, went down the route of stripping and rebuilding my 7 when it was 15 years old over the winter of 2007/08. It took me just 36 hours over a few weekends to strip it down to the bare chassis and I was no mechanic, but I learned an awful lot on the rebuild. Arch carried out a few repairs and repowder-coated with zinc phosphate primer and repanelled for approx £2.25k. In addition to the chassis I also had everything that was previously powder-coated re-powder-coated i.e suspension etc. Photos here
Remember to make a template for the hole in the sideskin for the primaries as there are so many engine variants
I, too, went down the route of stripping and rebuilding my 7 when it was 15 years old over the winter of 2007/08. It took me just 36 hours over a few weekends to strip it down to the bare chassis and I was no mechanic, but I learned an awful lot on the rebuild. Arch carried out a few repairs and repowder-coated with zinc phosphate primer and repanelled for approx £2.25k. In addition to the chassis I also had everything that was previously powder-coated re-powder-coated i.e suspension etc. Photos here
Remember to make a template for the hole in the sideskin for the primaries as there are so many engine variantsNice work, the trouble with a re-chassis on any vehicle is that you end up doing the whole lot, Lol, It's too much of a shame to put older/scruffy parts back into a nice shiny body and whilst it's all out, you think, well it makes sense to sort this and that out etc.
It looks superb and your website was a fun way to avoid kids bath time
Love the models. Your not tempted by this Scalextrics model then £180 Ouch!
http://www.ebay.co.uk/itm/Scalextric-C3435-Caterha...
It looks superb and your website was a fun way to avoid kids bath time
Love the models. Your not tempted by this Scalextrics model then £180 Ouch!
http://www.ebay.co.uk/itm/Scalextric-C3435-Caterha...
Edited by Zagster on Tuesday 21st May 18:25
So it's not quite correct that Arch do a better job when not constrained my Caterham. There was a crossover in the mid-late 90s where they improved/changed the zinc phosphate priming. They being Arch and Caterham together. I would expect the OPs chassis to be of the later type.
To the question, I think it's really hard to treat existing corrosion without changing the panels. If it is "external" then it can be rubbed down and repainted. That might be enough, but might not. Unfortunately the only way to tell is to get the paint off and see.
Bert
To the question, I think it's really hard to treat existing corrosion without changing the panels. If it is "external" then it can be rubbed down and repainted. That might be enough, but might not. Unfortunately the only way to tell is to get the paint off and see.
Bert
Shaun_E said:
I also had all the panels powder coated on the inside which provides another barrier between the aluminium and steel and may help reduce future corrosion. The only one they can't powder coat is the rear panel. My car is a 1997 car.
All the panels like the floor panels? I'm assuming that you didn't have the outer skin powder coated as you can't just do the one side can you. I'm being silly aren't I!Gassing Station | Caterham | Top of Page | What's New | My Stuff