Painting aluminum body
 

I was just wondering, has anyone had paintwork done on the aluminum body of your X150? Is it really necessary to go to a Jaguar-approved body shop, or can most body shops handle painting on aluminum these days?

Not a great amount of help here, but I did have a Jag approved shop do the work... Mostly because the paint was covered by insurance.
That said, if no seriousbody work is needed (repair of alluminum is certainly different than steel), I see no reason a competant paint shop can't do the work just as well.....

Vince

I am sure there are exceptions, but basically, if anything touches an aluminum car, it needs to not have touched a steel one before. Since paint work doesn't involve too much touching, you should be ok.

That being said, if it were me, I'd be using a shop certified with aluminum work. Why risk it?

the guy said today as long as they paint on top of your actual paint it is not on the alu body then....

Could you elaborate on this? What happens if a tool used on a steel car is then used on an aluminum one?

The list I found on Jaguar's website of approved shops seems to be at least 5 years old as it contains shops that are no longer in business.

Let me try, i need to have some alu repainted (top of the rear above "jaguar chrome rear boot ) and i asked him it is aluminium not metal, and he responded, it does not matter as i will be painting on top of the paint, not on the alu....

I do not know the tool used on metal to elaborate on that one.

With different words i will say this, if he had to sand the actual paint but not deep until the alu, then he will be painting on your actual paint and not on aluminum. it is not like the initial job to paint aluminium parts.

Aluminium requires a different primer if the paint is sanded all the way down to the aluminium. Just scuffing your paint so that the fresh paint adheres doesn't require the special primer. I've painted some aluminium parts and an etching primer has to be used for the paint to stick to it. In your case, just scuffing the paint won't require the extra step.

I'm not exactly sure, but I've toured a shop that works on aluminum cars, and they had an entire separated section for the aluminum stuff and the guy told me that the main thing is that the tools can't touch steel. Maybe it has something to do with electrolysis.

That's what I thought. But it seems like this is not very well established on the forums--people seem to have differing views on what is different about having bodywork done on an aluminum car and why it is so!

this is an interesting read.

Reserved for Aluminum - FenderBender - January 2013 - United States

It really has nothing to do with the tools.... As a aricraft mechanic, my tool chest was filled with Craftsman and Mac tools just like any car shop. Metalurgy only comes into play on things like the type of sand paper used (you dont use iron ozide grit), and welding techniques. Beyond that, tools are tools.
For repair, the malability of aluminum will take skilled hands, as it is easier to damage if mistreated.

As pointed out, aluminum will require special primers and paint prep, but a skilled paint shop would know these facts.

Vince

This is from the X350 body repair guide:

Galvanic Corrosion and Housekeeping

Galvanic corrosion is the ‘cross-contamination’ of dissimilar metals, in this case aluminium and steel. Avoidance of galvanic corrosion is an important issue to be considered in the repair of aluminium bodied vehicles.

Precautions to prevent the contamination of exposed bare aluminium surfaces should be taken.

Good housekeeping / cleanliness should be adopted throughout repairs and especially prior to welding, pre-treatment and adhesive bonding.

The repair environment requires control and protection from dust and debris from conventional steel body repairs. All equipment used must be clearly identified and used solely on aluminium. Tools should be kept clean and in good order. Steel fastenings are coated to prevent galvanic corrosion.

Fastenings should be examined during repairs and where damaged or suspect must be renewed. The use of graphite, ‘penetrating’ oil or copper based anti-seize compounds upon the steel fastenings is not recommended.


And for the painting process:

Following completion of appropriate panel repairs carry out the following actions:

– Clean original paint surfaces with soap and water, rinse and wipe dry.
– Preclean with Prepsol 3919S, or 3910WB Waterborne Degreaser.

Dry sand with P280 – P320

Sand bare aluminium surfaces using Grey Scotchbrite with 3608S to remove all traces of oxidisation.

Degrease with 3920S or 3911WB Waterborne ‘Final Clean’.

Wipe dry and tack wipe before priming.



Epoxy Primer Coat
Product Preparation Mix:
– 4 parts 830R Epoxy Primer.
– 1 part 835R Epoxy Activator.
– 2 parts 3871S Thinner.

Apply 1 full coat of 830R Epoxy Primer. Flash until ‘flat’ before baking. Bake for 45 minutes @ 60°C.
Recommended Film build: ± 35μ dry.

Once the epoxy primer is cured, dry sand mechanically with P280 – P320.
Degrease with 3920S or 3911WB. Wipe dry and tack wipe.

Note:
If bare metal is exposed during sanding, repeat epoxy
primer process.



Primer Surfacer Coat
Preparation Mix:
– 2 parts 3240S UHS Primer.
– 1 part 3206S Activator.
– 3% 3289S Accelerator.

Apply 2 full coats 3240S UHS primer surfacer.

Flash for 10 minutes between coats and for 15 minutes before bake.
Bake for 20 minutes @ 60°C.
Recommended film build: 50 – 100μ dry.
Dry sand, initially with P320 finishing with P400 – P500.
Degrease with 3920S or 3911WB. Wipe dry and tack wipe.



Basecoat / Clearcoat
Basecoat preparation is not required as Cromax® (a water based basecoat colour) is supplied from formula ready to
spray.

Apply 2 coats wet – on – wet, followed by optional ‘mist’ coat for metallic and pearl.

No flash time required between coats.

Flash until completely dry (if required, use suitable air blower system) before application of Clearcoat.

Clearcoat Preparation Mix:
– 3 parts 3800S Chromaclear® HS Clearcoat.
– 1 part XK205 Low Emission activator.

Apply 2 coats, allow to flash for 5 – 10 minutes between coats and for 0 – 5 minutes before bake.
Bake for 30 minutes @ 60°C.