what's the concensus=is factory paint superior to reconditioning one ?

Chip Douglas · 09-23-03, 11:00

I've heard differing opinions on this so far, and would like to start a thread on it : *is today's reconditioning paint as good and durable as factory one ?

Some say reconditioning paint as now as good as factory's .......it'd be interesting to know from some of you guys in paintshop/bodyshops, what'S the lowdown on paint durability. All i know is a lot of painters now deal with renowned company such as Dupont, PPG,house of colors....and i think most manufacturers use Dupont line, but i may be mistaken here.

Usually, as i've always heard, repaints don't last as long as factory paint, prolly cause the paint is not baked at all, or if baked, is not as high a temperature as it should, but of course it cannot be cause it would melt plastics and such.

I'm quite certain, this thread might be interesting.

take care all

SP 325i · 09-24-03, 02:36

Can I just throw some facts into this thread:

OEM paint system is as follows

electro paint - this is applied by a dip process using an electric charge to "attract" the product to the metal car body - gives the corrosion protection - not sure on film thickness

primer / surfacer - this does not offer corrosion protection except for being an extra barrier between the elements and the metal. It is usually applied by a combination of automatic robot spray equipment with hand spraying in places like door jams, under bonnet (hood) and places the robot is unable to reach. A lot of car companies are using colour coded primers to help final colour and so that they don't have to spray some parts with topcoat ie under bonnet. Around 20 microns is applied and baked at 160°C for 20mins. This surfacer can help with stonechip performance.

colour coat - applied at around 10microns. Offers protection as a barrier coat and gives the cosmetic appearance. Also cured at around 160°C for 20 mins. Formulation can have an impact on stonechip resistance. Usually higher pigment loading worse for stonechip also Japanese have a number of harsh visual criteria for orientation and placement of aluminium / mica particles if used in a formulation.

clearcoat - offers protection mainly to colour coat and helps give good gloss, depth of image to mica / aluminium colour coats. Applied at 15micron baked 20 mins 160°C. Also key to stonechip resistance. A very hard clearcoat has good marr resistance but is more likely to show problems with stonechips and maybe even crazing. A softer clearcoat vice versa.

Other developments :
at the steel production stage the galvanised steel can be coated with a very thin (2 - 3 micron) anticorrosive layer. This has been shon to improve drastically corrosion resistance and stonechip performance.

All OEM paint has a crosslinking sytem that requires the temps mentioned to cure the paint.

Refinish paint:

For me personally when people talk about bare metal respray I think what has happened to all that corrosion protection that the manufacturer put on ? (newer cars mainly - not your classics)

I will talk about PPG Deltron type products.
Primers have corrsion inhibitors built in and are applied to a thickness as required. Many different ones exist from etch primers to high build that can fill some defects. These crosslink using a isocyanate which happens at room temperature(why there is a limited potlife) or low bakeconditions (speeds up reaction). Low bake can produce solvent boil if the paint is applied too wet and thick (if you look at OEM temps this is one reason why film thickness is so low). The colour coat and clearcoat follow the same rules. The colourcoat, if being clearcoated is not usually activated.

Both modern OEM and modern refinish paints crosslink to give a tough surface. The main difference (wthout going into the chemistry) is the film thickness that can be applied and that refinish paints will cure at room temperature.
As with everything the key to a good repaint is the preparation. If everything is done meticulously I can see no reason why a repaint shouldn't last as long as an OEM finish. Corrsion under a repaint is the usual problem but this can be avoided by good working practices and an understanding of paint systems.

sorry for rambling

Steve

SP 325i · 09-26-03, 02:15

Sorry chip, looks like I killed this one !!!!!!!

Steve

Lowejackson · 09-26-03, 01:13

Quote:

Originally posted by SP 325i
Can I just throw some facts into this thread:

OEM paint system is as follows

electro paint - this is applied by a dip process using an electric charge to "attract" the product to the metal car body - gives the corrosion protection - not sure on film thickness

primer / surfacer - this does not offer corrosion protection except for being an extra barrier between the elements and the metal. It is usually applied by a combination of automatic robot spray equipment with hand spraying in places like door jams, under bonnet (hood) and places the robot is unable to reach. A lot of car companies are using colour coded primers to help final colour and so that they don't have to spray some parts with topcoat ie under bonnet. Around 20 microns is applied and baked at 160°C for 20mins. This surfacer can help with stonechip performance.

colour coat - applied at around 10microns. Offers protection as a barrier coat and gives the cosmetic appearance. Also cured at around 160°C for 20 mins. Formulation can have an impact on stonechip resistance. Usually higher pigment loading worse for stonechip also Japanese have a number of harsh visual criteria for orientation and placement of aluminium / mica particles if used in a formulation.

clearcoat - offers protection mainly to colour coat and helps give good gloss, depth of image to mica / aluminium colour coats. Applied at 15micron baked 20 mins 160°C. Also key to stonechip resistance. A very hard clearcoat has good marr resistance but is more likely to show problems with stonechips and maybe even crazing. A softer clearcoat vice versa.

Other developments :
at the steel production stage the galvanised steel can be coated with a very thin (2 - 3 micron) anticorrosive layer. This has been shon to improve drastically corrosion resistance and stonechip performance.

All OEM paint has a crosslinking sytem that requires the temps mentioned to cure the paint.

Refinish paint:

For me personally when people talk about bare metal respray I think what has happened to all that corrosion protection that the manufacturer put on ? (newer cars mainly - not your classics)

I will talk about PPG Deltron type products.
Primers have corrsion inhibitors built in and are applied to a thickness as required. Many different ones exist from etch primers to high build that can fill some defects. These crosslink using a isocyanate which happens at room temperature(why there is a limited potlife) or low bakeconditions (speeds up reaction). Low bake can produce solvent boil if the paint is applied too wet and thick (if you look at OEM temps this is one reason why film thickness is so low). The colour coat and clearcoat follow the same rules. The colourcoat, if being clearcoated is not usually activated.

Both modern OEM and modern refinish paints crosslink to give a tough surface. The main difference (wthout going into the chemistry) is the film thickness that can be applied and that refinish paints will cure at room temperature.
As with everything the key to a good repaint is the preparation. If everything is done meticulously I can see no reason why a repaint shouldn't last as long as an OEM finish. Corrsion under a repaint is the usual problem but this can be avoided by good working practices and an understanding of paint systems.

Steve

That is exactly what I was thinking

Chip Douglas · 09-26-03, 10:01

lol, no worries there Steve.......i must say that was a very informative post on your part

.......im very happy with it, i mean really.

take care

BoxsterCharlie · 09-28-03, 10:58

For my part, I wish we had more painters here. Maybe painters and detailers are just totally different types of people (besides that 99% of painters would be pro), maybe painters don't give a hoot about detailing because they can just do a respray!

Chip Douglas · 09-28-03, 02:02

BoxterCharlie, i think you said it all in your last sentence, ive been thinking the same as you, that painters just dont care much about detailing as they can respray at will lol

Scottwax · 09-28-03, 10:37

I think it depends on the factory doing the painting and the repainter as to which is best.

Properly repainted, the paint should last as long as factory and if the painter knows how to wetsand and buff, it will also have much less orange peel than factory paint (Bentley, Rolls, Lamborghini excepted). If they remove the trim, lights, bumpers, etc so there is no need for taping, you won't have peeling paint a year down the road either. If they use a lot of tape, you can expect peeling at some point. Proper repaints are expensive though....expect $2500 minumum for a small car that needs little or no body work (as in a few door dings). Most cars run about $3500-5000 for a factory or better quality repaint.