Respraying a car.

obi_waynne

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Not really sure about this but I've been talking with some guys and researching the subject but would really appreciate your take on this article before it makes it to the main site:-

Here it is spelling mistakes and all.

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Respraying a car.

Preparation is 150% of the job. If the surface to be painted is not completely smooth and free of dust, grit and residue then forget it. We will deal with bodywork repairs in another article and just focus on the act of painting a car or respraying the car.

Before you start:
Make yourself a spray booth. Clear plastic sheeting on a wooden frame is best but you can improvise by using sheets of cardboard to line your garage wall and floor. Ensure that the area you paint in is completely dust free and make sure that you are not spraying your car on a windy day. It also helps if you are respraying your car on a warm day.

If you are after a flip paint or special effect you must ensure that you buy the right paint!

Paints all behave in very different ways and come in the following main types acrylic, metallic, pearlescent, translucent and the techniques for application of these paints are not the same. We are assuming a standard acrylic paint for this guide.

Safety.
Paint fumes are not healthy to breathe in. A decorators dust mask will not protect you. You need good filtration to take out paint particles and you need to ensure that the area you are painting in has a good supply of fresh air and is well ventilated.

Equipment.
Spray paint cans will never give a professional finish and are actually expensive when compared with the cost of hiring a good quality spray gun and the paint. Check how much area the tin of paint covers to see what I mean and remember that you want to be doing 3-5 coats of paint.

Step 1: Wash down the area to be painted thoroughly all sanding and filling has to have been done before you get to this stage. Ensure all grit, dust and road film is removed by using a good quality car cleaning fluid WITHOUT a wax additive. Washing up liquid does a good job as this strips most of the wax, oil and bug residue from the car.

Step 2: Clinical cleansing. Using a paper towel or preferably a screen wipe and solvent cleaner such as IPA or similar spirit wipe over and buff off the surface to a smear free finish.

Step 3: Masking. Any exposed area of the car is going to get painted - just a few mm out with the masking and you will have really annoying over-spray lines. Masking is even more important, if you are changing the colour of the car, and you should pay attention to all of the seams IE open the doors, bonnet etc and take out the glass (when the windscreen goes and is replaced you do not want a small patch of the old paint showing through.) In a perfect world the car will just be a shell with all plastic and interior removed.

Step 4: Spraying. Ensure that you have a good flow of paint so test on a scrap of card - you need to look out for blobs and splatters. Do not aim to completely cover the metal just spray a fine mist over the surface - a load of thin coats of paint is much better than a couple of thick coats. Keep the spray gun moving at a regular pace from left to right on the first coat then up and down on the next coat. Try to view the car as a whole rather than just painting a panel at a time (if you are respraying just one panel you need to blend the paint in to the surrounding panels as most if not all paints fade over time.) Ideally leave 1 hour between coats of paint.

For some paint you need to finish with a final lacquer coar. The final lacquer coat will be the last you apply and even this can be applied in a couple of thin layers.

Step 5: Finish off with a fine grit of wet and dry paper then polish off with a cutting paste and then apply a good quality polish - this protects the car when you are refitting the parts you stripped off it.
 

Freddie

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Surrey
A handy little guide.. I think possibly more is need on the preperation side of things? I'm still confused wether I would need to sand away old paint, and all the way back to the metal?! I might have missed this in the article..

And IMO the 'drying times' would state 'ideally' more than 1 hour.. If you tell people one hour, they will always cut corners and make it half an hour, so if you tell them alot longer (I think it needs alot more than an hour to cure anyway?!) then they are less likely to cut corners on drying times: it's just human nature.

I'm sure James would like to have some input to this article, but thats my two cents.
 

obi_waynne

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Yup fair comment - the final dry time needs to be a lot longer. Not sure if a bare metal respray is necessary unless we are treating rust. I'll be interested to hear James' comments on it as he's in the business.
 

the_names_james

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Surrey, UK
Firstly, I'd say prep is 65%, painting is 25% and flatting/polishing is 10%.

I don't think this is a good idea. The materials you'd need for a proper job are illegal to spray without a filtered booth. I have never used acrylic paint, all I use is base/clear. The hardener in the clearcoat is carcinogenic.

I have to go out. I'll comment again another time if you choose to go ahead with it.
 

obi_waynne

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You make a good point James - perhaps the article should be aimed at the minor repair rather than a complete respray. We certainly don't want to encurage people to risk their health & the environment and it is our duty to give both sides.

Do you think people could do a wing respray with a can and get a good enough job to blend with the rest of the car :?:

The message may need to change to "the only way to get a proper job is to go to a pro with a spray booth and they will ....."
 

the_names_james

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From
Surrey, UK
waynne said:
You make a good point James - perhaps the article should be aimed at the minor repair rather than a complete respray. We certainly don't want to encurage people to risk their health & the environment and it is our duty to give both sides.

Do you think people could do a wing respray with a can and get a good enough job to blend with the rest of the car :?:

The message may need to change to "the only way to get a proper job is to go to a pro with a spray booth and they will ....."
Nope.

The only way you'd get a fairly respectable finish is by using a compressor and spray gun, but there are many variables, including: temperature, air pressure, paint viscosity, what type of gun setup you use, what type of thinner you use, user ability, etc...

The only thing I'd be happy to paint using aerosols is interior trims, or maybe small stuff like door mirrors or handles, but it depends on the colour.
 

obi_waynne

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Thought as much! I need then to make this article more of a what the professionals do.

Paint types I have found so far:-
Acrylic, base, Metallic, Pearlescent, Flip, Candy, Chrome, Clearcoat

Any other types out there?
 

the_names_james

Torque Junkie
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Surrey, UK
Most (if not all) bodyshops use a waterbased basecoat. Laws were revised a couple of years ago, limiting the amount of VOC's (volatile organic compounds) released into the environment.

Alot of the 'paints' you listed are effects.

Check here
 

COMBOM

New member
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hi all,

Can anyone help. I attempted to do a scratch repair myself. all was going well until I was advised to not bother with a sand block for such a small area and to just fold the wet and dry several times and just use the edge. it looked fine until i noticed what looked like pimple dents. I was shocked in disbelief as the car is a VW, the shell is thicker than other cars like ford etc. It looked like the dents were very small but noticeable in the light. could it be because of the way I sanded it down causing it to look like dents???

also anyone know a good body specialist in Milton Keynes or Stevenage??


thanks in advance for your advise
 

jennifertom

Newbie
Points
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A quick note before we begin. Always check the local rules and regulations regarding the use of automotive paints. Often times it will be illegal to spray these paints at your home and you may need to look for an alternative location. In a lot of cities you can actually hire out spray booths by the hour or day/half day and this would be better than upsetting everyone and maybe even facing a fine.
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jennifertom
 
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billyo

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I used an eraser as a sanding block for some stone chips which worked well. A bit of tcut will improve the finish and might even remove the "dents" you see as I suspect they are just flat paint. Have you spray painted the scratches?
 

TITAN

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Honda Civic EG
i know that its unadvisable to do a full re-spray yourself and you wouldn't be able to get a pro finish however how do people afford full resprays as i've had 2 qoutes and one said £1200 and upwars and the other said £600-£1800
 

obi_waynne

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You are paying for quite a bit of workshop time and the tools and skill of the operative. Most also use a low bake oven to set it off hard. It is something you need to save up for and should be the last visual mod you do. You can't beat it and its just like getting a new car. I'm still too skint to get my wing sorted! :( So you are not alone.
 

TITAN

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haha ye i need to sort out my wing as well. my garage is only about a foot wider than my car and it is on a hill and i accidentally accelerated too hard and took some of the paint off the wing and theres a small dent as well. oops :blink:
 

obi_waynne

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OOH! I've done that with a wing mirror. At least a mirror was cheaper to fix. My dented wing was a hit and run job.
 

pgarner

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dont spray so much,

follow the instructions on the can - normally spraying horizontally approx 10" from the panel in light coats.

many thin coats is alot better than one thick coat that is full of runs as this would require to be wetsanded back down level before another coat
 

obi_waynne

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Even with a spray gun you need to apply a mist coat. It should take about 3 or 4 sessions to cover the metal, doing more than this causes runs and the paint can just flake off.

The most common mistake when trying to start out spraying a car is to do it in just one or 2 coats. It applies to spray guns and cans alike. If you have a heater then you can accelerate the drying time between coats
 

hg70

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australia wollongong
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91 st ford econovan
A handy little guide.. I think possibly more is need on the preperation side of things? I'm still confused wether I would need to sand away old paint, and all the way back to the metal?! I might have missed this in the article..

And IMO the 'drying times' would state 'ideally' more than 1 hour.. If you tell people one hour, they will always cut corners and make it half an hour, so if you tell them alot longer (I think it needs alot more than an hour to cure anyway?!) then they are less likely to cut corners on drying times: it's just human nature.

I'm sure James would like to have some input to this article, but thats my two cents.

you can leave the original paint on providing you rough it up with fine grit paper so the primer has something to bite to, as waynne said research your paint, i give all my re-sprays 48 hours (24 hours total of hot sun) to fully cure and plan it for a warm sunny weekend if you can.
 
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