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Old 30th October 2014, 11:34   #16
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Default Re: All about car dent repair & painting - Processes, methods & tools

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Originally Posted by rangarx View Post
Thanks for disseminating the knowledge. having worked in an automotive paint shop for 9 years, this whole thread is like re-calibrating myself. Brilliant!
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Originally Posted by MaheshY1 View Post
Can't thank you enough.
So much information, the problems, and the solutions to all of those problems.
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Originally Posted by Inquisitive View Post
What an excellent article, Joy, as always!! Rated a very well deserved 5 stars!! Anybody with an absolutely zero level of knowledge about denting and painting would be well advised to go through your post and make informed decisions henceforth.

I was fortunate to be guided by him to tell them exactly what I wanted and more importantly what I did not want them to do on my car. I think there are two sides of this article.

Thanks again Joy for this wonderful thread!!
Thanks rangarx, MaheshY1, Inquisitive. Glad you liked it. Inquisitive, your travails was the inspiration.



Quote:
Originally Posted by jinojohnt View Post
1. Would it help if 'clear coat' is applied to the whole car after one panel is repainted? Would this help to reduce color difference that happens after a few months?
Not at all. Clear coat is a transparent layer protecting the layers below from damage by the sun/dust/smoke/humidity/salt/even minor abrasions. The clear coat and the paint layers below start to degrade depending on their relative exposure to the UV light of the sun and the other elements.

Adding additional coat of clear on the rest of the panels would not serve any useful purpose. It won't put the lost color back. Its just a transparent layer. On the other hand, you run the risk of adhesion failure, which is when flakes and cracks appear because the new layer of clear may not be able to stick properly to the layer beneath. Besides if you key the surface before you apply this layer of clear, then you have essentially ended up throwing out the older layer of clear coat.

On a new car or a car which has recently had a full body respray, and having occasion for a subsequent panel repair/repaint - a normal paint job is more than sufficient.

On a older car, where the paint has been subject to degradation, the better way is to paint the panel in the factory color , then sand entire surface back to primer and apply two or three base coats and a layer of clear (if you can afford it). If not, just live with the imperfection.

Quote:
2. One of my colleagues mentioned that he got one panel of his car repainted from a 'hot' paint booth (some thing like a covered paint booth with increased ambient temperature). He says that this procedure is useful for minimizing color difference in the long run. Would this really help?
See post # 2. A paint booth is Nothing fancy. It's just a place where a clean environment is maintained, and air extractors and Infra red lights and hot air circulation plumbing is provided. The way it helps is that :
a) Foreign particles such as dust or water droplets do not ruin the paint work.
b) Infra red lights and hot air circulation, allows the paint to cure better. Leading to better adhesion to the primer layer.
c) usually comes with one or more supports for hanging the panels while working on them. Makes for a much better output in terms of job quality - as opposed to 'on-the-car' painting.
d) Using a paint-booth by itself will not solve the color difference problem.

Think about it this way, say a color blind painter uses a paint booth - he may end up painting a panel green instead of blue? Like I said earlier, paint matching is an art and depends on a keen eye or a very good spectrophotometer.
What your friend may have implied, is that he went to the dealer, who had a paint booth. And BTW - the dealer supplied tins of the factory color. There's no difference that the existence of the paint booth itself made to the color matching - right?


Quote:
3. How is repainting done in other countries such as the US and UK? Do they also have this 'color difference' problem after a few months?
Exactly as described in the article above. Yes they have this color difference problem too. Sometimes more than in India. The sun shines in the US or UK just like it shines in India. Same Sun more damage - because the ozone is thinner there so more UV. Damage is higher in the coastal areas, as well as areas where there's more snowfall. Why? Coastal areas - more humidity - water is a fantastic corrosive agent. Given enough time it will dissolve iron; In areas where there's snow, aside from all that freezing temperature, there's also salt spread on the road - which sticks to the body. And that has a corrosive effect.


Quote:
4. Can somebody list the colors that are less prone to this 'color difference after a few months of repainting one panel'. I know White and Silver are good in this.
All paint colors would degrade. The question is would it be perceived more or less. The human eye is more sensitive to bold colors - hence reds, blues, greens, will appear to have degraded more than whites. But if one were to measure the color of a white car right off the factory floor using a spectrophotometer and the same car 1 year later - you would find a difference in the values.
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Old 30th October 2014, 11:35   #17
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Default Re: All about car dent repair & painting - Processes, methods & tools

Very detailed and enlightening thread joybhowmik. Thanks a ton for sharing. With modern cars getting nicer looking paint jobs before they roll out of the factory, its becoming increasingly difficult to get a similar finish with repainted surfaces. I guess some colours tend to be more difficult than the others. Could you also share you experience with scratch removal (if any)? In todays traffic, scratches are a real nightmare and in cases where they have not gone through the clear coat and could still be fixed, it would be good to know any DIY techniques. I have gone through this already (http://www.popularmechanics.com/cars...enance/4216365), but a more Indian touch would be appreciated .
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Old 30th October 2014, 12:12   #18
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Default Re: All about car dent repair & painting - Processes, methods & tools

Great thread. Thanks for sharing.

But I have one question, and I am sure I am not the only one: I have this mental block about getting denting/painting work done anywhere else but at the authorized workshop. It feels a whole lot safer, mostly because you know that they will use the correct tools, techniques, and materials. But yes you need to be prepared to pay extra $$$. Is this not a valid line of thought?

I have had body shop work done on my Polo at two VW workshops, and the results are always fantastic (at least to my untrained eye). The only problem is that VW does not allow its authorized workshops to do partial repairs (which sends the cost shooting up). That is what both told me. Were they lying?

And finally, can you bargain with an authorized workshop when it comes to the cost of a denting & painting job? Aren't they mostly standard? Pardon my ignorance if this feels like a silly question.
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Old 30th October 2014, 12:49   #19
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Default Re: All about car dent repair & painting - Processes, methods & tools

Thank you joybhowmik for the enlightening article.

Adding on to the query by TheLizardKing - My VW SA had once told me that VW uses a water based solvent/paint and it is extremely difficult to source water based paint at outside workshops. The painting done by non VW workshops would use an oil based paint and therefore however hard we try, we will never get the color as specified by VW.

Is this true ?

I have noticed that the local workshops remove the fuel cap and take it to the paint dealer to get the color match done. Do not know if they then use a manual or computerized process to get the color mix.
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Old 30th October 2014, 13:30   #20
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Default Re: All about car dent repair & painting - Processes, methods & tools

Thanks Joy.

Will use this article for future reference.

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Originally Posted by TheLizardKing View Post
But I have one question, and I am sure I am not the only one: I have this mental block about getting denting/painting work done anywhere else but at the authorized workshop. It feels a whole lot safer, mostly because you know that they will use the correct tools, techniques, and materials. But yes you need to be prepared to pay extra $$$. Is this not a valid line of thought?
LizardKing, most authorised workshops I know of, outsource the tinkering and paintwork to contractors. The output you get depends on the skill/workmanship of the men employed by these contractors. Usage of good paint, thinner and availability of a paint booth does help in the process.

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Originally Posted by TheLizardKing View Post
I have had body shop work done on my Polo at two VW workshops, and the results are always fantastic (at least to my untrained eye). The only problem is that VW does not allow its authorized workshops to do partial repairs (which sends the cost shooting up). That is what both told me. Were they lying?
Certain manufacturers do impose such standards but it all depends on the rapport you maintain with the dealership

Quote:
Originally Posted by TheLizardKing View Post
And finally, can you bargain with an authorized workshop when it comes to the cost of a denting & painting job? Aren't they mostly standard? Pardon my ignorance if this feels like a silly question.
Bargaining does work - we are Indian after all ! Large fleet owners usually work out discounted rates to ensure their vehicles are properly looked after.

Quote:
Originally Posted by kutts View Post
Adding on to the query by TheLizardKing - My VW SA had once told me that VW uses a water based solvent/paint and it is extremely difficult to source water based paint at outside workshops. The painting done by non VW workshops would use an oil based paint and therefore however hard we try, we will never get the color as specified by VW.

Is this true ?
kutts, Water based paints are slightly more difficult to source but it's not impossible to find either.

Quote:
Originally Posted by kutts View Post
I have noticed that the local workshops remove the fuel cap and take it to the paint dealer to get the color match done. Do not know if they then use a manual or computerized process to get the color mix.
There is nothing wrong in this process and I know of many authorised workshops who do the same.
I don't know of any paint dealers who use spectrophotometers to ensure a proper colour match especially for vehicles where the paint has aged significantly.
Hence, some adjustments on top of the default formulations are inevitable i.e. depends on a trained eye and the skill of whoever prepares the paint at the paint dealer.

Last edited by bikertillidie : 30th October 2014 at 13:40. Reason: To aid clarity
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Old 30th October 2014, 13:52   #21
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Default Re: All about car dent repair & painting - Processes, methods & tools

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Originally Posted by SS-Traveller View Post
Hi Joy, it would be interesting to compare the ideal processes described by you to what commonly happens with our FNG denters-painters. Could you mention:
  • Different qualities of paint and primer available in the market
  • Cost-cutting methods used by them
  • Different types of body filler / putty being used by them, and their longevity
  • How these people manage hard-to-reach dents such as running boards
Hi SST
You have asked me in essence to write another treatise. Well my wrist is aching from the last response to another gentleman, but I'll try to do my best nonetheless.

If one were to ask me this question - my short answer would be
"FNG mechanics try and achieve the impossible through skill alone." And here lies the problem. While the technique may be honed with years of practice, they severely lack in proper tools, and more importantly to keep operational cost down they compromise on material quality & quantity.
Dealers on the other hand, are mandated to carry all the requisite tools, and materials by the manufacturer - else they run the risk of losing accreditation. So they cut costs by compromising on human resources. Attrition is usually high, so skills and competence are always to be watched out for. Secondly the mechanics are on the clock, so they are always in a hurry to get the job done quicker - sometimes at the expense of the poor customer.

Well enough philosophizing about the travails of us poor car owners/drivers.

1) The first problem with FNGs is they dont have access to a paint booth. All their work is by the roadside. I have already enlisted the issues that this exposes the job to in an earlier post.

2) Washing:
The process of washing should be undertaken with a initial pre-spray followed by soaping down the entire body using micro-fibre cloth. This gets rid of surface contaminants without leaving any marks on the surface. This is finished with a finishing spray, to wash off the soapy residue.
What the FNG mechanic employs is a rag and hopefully clean water:
Source: Google images
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3) Removal of badges and trim:
The process should be approached with genteel and using the appropriate tools that I have detailed in the article.
What the FNG mechanic employs is a screwdriver. He can end up scratching the trim as a result if it slips.
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4) Sanding the creased area to bare metal
The process requires that the creased/dented area be sanded back to bare metal.
Consceint FNG mechanics will do this - but will take a long time about it because they would use 50 # or 80 # paper. Normally they won't own an angle grinder.
Others won't even bother.

5) Using the right dent removal tools and methods
a) For panels that can be easily accessed, the process requires one to take the panel out, and then fix the dent using the hammer off and hammer on technique (described in an earlier post).
This ensures that absolutely the minimum amount of body filler is needed.
What FNG mechanics usually do is to fix the dent in-situ. They don't bother to take the panel out and fix it using above technique.
They also don't have a variety of hammers, dollies and spoons at their disposal. They make do with the generic peen hammers (shown in one of the earlier posts) , a regular file (which they use as a shrinking dolly) All about car dent repair & painting - Processes, methods & tools-file-tool.jpgand a screwdriver

Invariably this leaves behind ripples, dings, small creases in the job. To be filled up with body filler of course. Less than ideal.

b) For panels that cannot be easily accessed, e.g. running boards.
The proper method requires either using a spot weld/slide-hammer (for easy to remove dent) or cutting out the running board using an ox-acetylene torch, fixing the dent, and plug welding it back (for dents where the creases are just too much).

Here's where the FNG's ingenuity is striking.
i) Option 1: Often they will use a chisel and hammer to open the seam weld, and then use a screwdriver + file to push out the dented area.

ii) Option 2: In other cases, especially when the crease is too much to handle using this method, they will punch holes into the running board - a bit like swiss cheese, and then use a screwdriver or a pick like tool to pry out the dent. Something like this picture.

6) Use and application of filler
The ideal process requires one to mix the filler and hardener thoroughly well. Typically a golf-ball size of filler mixed with a pea-sized drop of hardener. Professionally run body-shops will sometimes employ an automatic mixer, which prevents air-pockets from remaining in the mixed filler. This translates to less air-pockets/pin-holes when the filler is applied.

At an FNG the fillers are hardly of top-notch quality (e.g. not 3M, but local brands like Esdee). Moreover these are not mixed properly (too much/too little hardener) , and way too much is used.
What they lack in terms of proper dent-fix tools, they make up for in filler. And as a result pin-holes appear - air pockets, and more importantly the filler does not have good bonding either intrinsically or to the metal. So this results in flakes some months/years down the lines - due to adhesion failure.


A putty is different from a filler. It's use is to fill the pinholes or other dings on the surface. Most FNGs don't use it.

7) Use of thinners/reducers.
The ideal process requires mixing thinners/reducers recommended by the paint manufacturer - or rather using a certain system.

FNGs will try to cut corners by using thinners/reducers of local or cheaper brands such as Esdee, Gradurat rather than the more established brands like Dupont.

The mixing of paint/primer and thinner has to be done in a specified ratio. More often than not they get this wrong as well, because they don't use graduated beakers (they don't have these).

8) Masking
The process requires use of brown paper , and high quality masking tape. Masking is to be done on all areas in direct line of sight from the part getting painted.

The FNG normally uses news print. Masking tapes are also of low quality, and sometimes come loose. Finally sometimes in a hurry they leave out obvious areas - such as tyres. The problems with newsprint and cheap masking tapes have been explained in a post earlier. Overspray is a serious concern with some FNGs. On occasion, my red Santro's black walled tyres have taken on a faint red color after having been worked on by FNGs.

9) Use of Degreasers and paper wipes
The process requires use of a good quality degreaser and lint-free paper wipe before beginning the primer, base-coat or clear coat.

FNGs use the cheaper thinners, and a dhoti to wipe the surface. Depositing a good amount of surface contaminants in the process. Sometimes they don't even use that. They simply spray on. They use the dhoti instead as a filter to mix paint and thinner.


10) Use of spray paint gun
The ideal process requires the use of different spec clean guns for primer and paint. See article.

Most FNGs hire spray paint guns/compressor from someone and they pay by the hour.
Such guns are often not cleaned well when returned, and in a hurry the FNG may not clean these thoroughly. Residues impact the final outcome.
The gun nozzle dia are usually not appropriate to the application -and may not even be recommended by the paint manufacturer . Over time and with abuse, the nozzle orifice wears down, leading to a less than perfect spray.
As the gun is on the clock, the FNG mixes hardener into the paint. This allows the paint to dry quicker than what the manufacturer recommends. All so, that the FNG can spray on more coats quickly.

11) Use of primer/paint/clear
The process requires one to use a system that works together chemically.

Most FNGs are unaware of this basic tenet, and to cut cost would buy generic primer and clear, and also mix undue quantities of adhesive (hardener) in the paint.
This leads to less than optimal curing time for the paint, and subsequent adhesion failures, flaking, cracking and erosion of paint.

Add to this their need to get the job done with half-a-litre of paint where 750 ml or even 1 litre of paint is needed. Resulting in use of feathering technique that attempts to blend the painted area with the rest of the surface. Ever try looking at such an area under bright light and at various angles? The edges of different shades show up easily. But beware, they may have charged you for the full litre. Another reason why I recommend buying your own materials and ensuring their use in the job , rather than contracting a fixed price for the job per se.

Quote:
Originally Posted by gurudutt View Post
Could you also share you experience with scratch removal (if any)?
Thanks gurudut for liking this thread. The best way to remove minor scratches is to use a good polishing compound and a good polishing pad.
Never use a rubbing compound as that can lead to erosion of the clear coat.
There are some DIY products out there such as Fix It pro (ebay /amazon for it). These are essentially pens with clear coat.
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These cannot handle all scratches - only the minor ones - which can anyway be polished out using the approach described.

Quote:
Originally Posted by TheLizardKing View Post
Is this not a valid line of thought?
I have already covered this point in my reply to SST. Your money, you choose.

Quote:
That is what both told me. Were they lying?
Remember the dealer is a business man. He is in it to make money. Now that you know the process, and assuming you have access to sufficiently large pool of mechanics and dealers, why can't you use knowledge and competition to bring price down? You have the tools at your disposal. It's up to you to use them (if at all).

Quote:
And finally, can you bargain with an authorized workshop when it comes to the cost of a denting & painting job? Aren't they mostly standard? Pardon my ignorance if this feels like a silly question.
Not at all silly. You can bargain for potatoes and onions at the roadside vend. Why not with the dealer? Read my recent experience here (Car runs over a stone- Dent below the door, Help needed) appropriate section reproduced here.
Quote:
To be honest, the first dealer I tried with had quoted me Rs 3.5 k (exclusive of tax). Both FNGs quoted between 1.5 to 2 k - but did not have the dent puller , and I did not want my running board looking like a piece of swiss cheese while they were at it. So I finally went to my regular dealer, and bargained to bring the price down by pointing out that they won't really be taking the entire running board to bare metal. It took some time though. It helped that I know most of the staff by name.
Quote:
Originally Posted by kutts View Post
Thank you joybhowmik for the enlightening article.
Welcome. Glad you liked it

Quote:
My VW SA had once told me that VW uses a water based solvent/paint and it is extremely difficult to source water based paint at outside workshops. The painting done by non VW workshops would use an oil based paint and therefore however hard we try, we will never get the color as specified by VW.

Is this true ?
I have recommended that you should buy your own paint. It's not true that you cannot buy water based paint. You need to locate a paint dealer who can supply the specific paint you need. Yes there are differences in the hue of a water based paint and an oil based paint. Moreover water based paints are environmentally friendlier. They dissolve in water and hence effluents are easier to treat , unlike aerosol based paints which just pollute the atmosphere.
But once you buy the water based paint , provided you can get the mechanic to use the right equipment to spray it on, nothing prevents you from going to an outside workshop.

Quote:
I have noticed that the local workshops remove the fuel cap and take it to the paint dealer to get the color match done. Do not know if they then use a manual or computerized process to get the color mix.
Fuel caps, and/or the plate on the inside of the engine bay contain the paint code. Paint shops use this code and a computer to pre-mix the correct quantities of primary colors to produce the shade you need. At a dealer, the paint comes pre-mixed.

Last edited by joybhowmik : 30th October 2014 at 14:15. Reason: Added a clarification to the last point
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Old 31st October 2014, 10:09   #22
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Default Article Extension: Replacement Panels & Cosmetic Repair of Bumpers

Thanks all for the wonderful response.

To make this article a little more comprehensive, there are two areas, that I felt needed special mention - Replacement Panels and Bumper Repair

Replacement Panels
In a few cases:
a) panels are just too far gone to be repaired after damage due to an accident or corrosion.
Source : Google Images
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b) the cost of repair far outstrips the cost of replacing the panel outright (especially where labour is expensive - e.g. parts of Europe, North America, Australia & New Zealand)

In such cases it makes sense to replace the entire panel by sourcing it either from:
1) A breaker's yard a.k.a. salvage yard a.k.a. wrecker's yard a.k.a. car graveyard

Parts can be cannibalized from other cars of the same model year/model, the panel stripped to bare metal and minor dings , dents or rust repaired, and the whole thing repainted.
Be aware that finding a replacement panel in one of these places is a bit of a shot in the dark. Not all yards may carry the parts one needs, due to obvious reasons. So a better way is to call around, and then actually visit the place before you buy the part.
In some of these breaker's yards , the management implements a recycle policy. What can be saved is taken off the car, and the rest is scrapped. In such cases, the panels are a little easier to find, though you need to pay a little extra for their services. In the Western US e.g. Arizona, yards exist , where panels need to be removed by the customer himself, so many a customer looking for parts, brings his/her own toolbox around.
Source: Google Images
All about car dent repair & painting - Processes, methods & tools-auto-breakers-yard.jpg

The closest thing we have to the Western breaker's yard is the Auto Scrap market. Such markets are famous in all our metros - New Delhi's Mayapuri market and Meerut's Soti Ganj market are infamous.
Source: Google Images
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2) Pattern parts makers
Pattern parts makers make replacement panels for a wide variety of makes and models. In the west there's a plethora of such pattern parts makers , and the replacement panels they provide are new and a lot cheaper than the equivalent part from the company / main dealer.

They usually have physical sales office as well as online presence , and ship parts within country in 24-48 hours sometimes less.

Here is an example storefront of a pattern parts manufacturer.
Courtesy: carbodypanels4u.co.uk
All about car dent repair & painting - Processes, methods & tools-store-front.jpg
So what's the catch? More often than not, the dimensions of such parts vary slightly from the original , which means:

1) Panel gaps, wide open shutlines , or even difficulty in fitting the part.
2) Increased labour to fettle the part into position - usually a time consuming process.

Pattern part makers are rare in India.

3) The main dealer
Or one can order the part from the main-dealer , in which case one pays top $$$ - for the part and the painting. I am yet to see a main dealer for a mainstream car company parting with just the panel.

Bumper (Cover) Repair
Like it or not, in many accidents however minor they may be, the plastic bumper cover commonly mistakenly identified as the bumper is the first point of impact. In major impacts, the bumper cover and bumper absorbs the shock of impact, and thus needs to be replaced.
In minor incidents - such as a biker knocking up against the rear at a traffic signal, the worst damage can be a cover that's got a depression, and possibly a few locks/fasteners broken - with no damage to the paint.
Image courtesy: Shankyz (Advice needed for SX4 rear bumper repair/replacement)
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In such cases, the neighborhood bumper repair person is one's best bet. Again there are two kinds:
1) The nomadic type who carry the workshop on their cycle
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2) The settler type , who actually have a shop in the local auto parts market.
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Both kinds charge a minimal amount of Rs 100/- to Rs 250/- to unfasten the bumper cover , pry out any dents using heat, fix minor tears , and even fixing broken snap on locks/fasteners with new plastic.

But remember this is only when the bumper cover has suffered minor damage. For major damage - e.g. major perforations or tears, get the bumper cover replaced.

Last edited by joybhowmik : 31st October 2014 at 10:23.
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Old 31st October 2014, 18:12   #23
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Default Re: All about car dent repair & painting - Processes, methods & tools

That's a comprehensive guide.
Just curious to know the opinion about the extend of colour fade.
Which colours are the worst and which ones are good. Maybe a rating in terms of the colour fading properties of various common colours.
Thanks again.
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Old 31st October 2014, 19:04   #24
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Default Re: All about car dent repair & painting - Processes, methods & tools

@joybhowmik Awesome thread.
Only those who like to experiment with their car and dealing with dents know how important this thread is. Learnt a lot.
I faced a scenario where I need to repaint a bent bonnet along with scratches in bumper and door. The mistake I did was to deal everything on my own with my Dad's assistance. Tried com-paint and some tools to repair the bonnet. Everything looked good for 3/4 months. Then, they started showing true colors and slight rust in bent area. I never realised it involved so much other than paint and clear coat.
Rated 5 stars
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Old 31st October 2014, 21:44   #25
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Default Re: All about car dent repair & painting - Processes, methods & tools

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Originally Posted by jfxavier View Post
That's a comprehensive guide.
Just curious to know the opinion about the extend of colour fade.
Which colours are the worst and which ones are good. Maybe a rating in terms of the colour fading properties of various common colours.
Thanks again.
Thanks jfxavier.
As I have remarked earlier - all colors fade with time. For some colors, the fading is perceptively more than others. Other things being equal (quality of paint, environmental factors and many other things) white and other light colors age better than darker colors.
To avoid color fade, try parking the car in the shade. If you must park outside in the sun, put on a reflective car cover.


Quote:
Originally Posted by balavj27 View Post
@joybhowmik Awesome thread.
Only those who like to experiment with their car and dealing with dents know how important this thread is. Learnt a lot.
I faced a scenario where I need to repaint a bent bonnet along with scratches in bumper and door. The mistake I did was to deal everything on my own with my Dad's assistance. Tried com-paint and some tools to repair the bonnet. Everything looked good for 3/4 months. Then, they started showing true colors and slight rust in bent area. I never realised it involved so much other than paint and clear coat.
Rated 5 stars
Thanks balavj27.
I did not want to comment specifically on com-paint on the main article. My own experience has been horrible. The biggest problem I have found is the pre-mix paint has possibly too much thinner. The result is that the color runs when sprayed.
I have therefore found it easier, to spray a small quantity into a upturned cap, and use that paint to gently touch up any small stone chip marks on my cars. That's about the only use I got from com-paint.
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Old 1st November 2014, 00:50   #26
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Default Re: All about car dent repair & painting - Processes, methods & tools

Joy. A thread that deserves a full five stars. You should update the wikipedia entry for automotive painting.

Now a straight crore paise question - so where in Delhi should one get a panel, or complete car painted?
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Old 1st November 2014, 15:21   #27
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Default Re: All about car dent repair & painting - Processes, methods & tools

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Joy. A thread that deserves a full five stars. You should update the wikipedia entry for automotive painting.
Thanks barcode.

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Originally Posted by barcode View Post
Now a straight crore paise question - so where in Delhi should one get a panel, or complete car painted?
There are a few FNGs that I go to, for odd jobs - the closest to my home is this (Friendly Neighbourhood Painter - Ramesh (New Delhi)), in which case I buy supplies for the job from here (Auto Paint Shop - RM Paints (Delhi)).

There's another FNG - close to where the supplies shop is. But, I have stopped going to him, as he messed up big time last I entrusted a job to him.

For big jobs - e.g. double sheeted metal repair , matching the paint exactly for bumper covers - (that's a bummer!) , or polishing the full car , I normally shop around, and after collecting enough information - I invariably end up going to the main dealer here. (Review: Galaxy Toyota @ Okhla Industrial Area, Delhi), I end up getting the best price here (always! - how that happens everytime even with different SAs each time around is another story).
Better still since I know most of the mechanics by name, they don't mind my hanging around when the job is being done, and intervening, in case I need things done in a certain way. They know I am passionate about the car and know the stuff - so sometimes out of the goodness of their hearts, they too go the extra mile.

Few years ago, I used to go to Pandit Auto - at Okhla, and a couple of other denter painters near Okhla mills, but have been dissappointed with them on subsequent jobs. I guess Pandit Auto unfortunately has succumbed to the bug which puts profit before customer satisfaction- but's that's only my view.

Last edited by joybhowmik : 1st November 2014 at 15:24.
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Old 4th November 2014, 18:08   #28
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Default Re: All about car dent repair & painting - Processes, methods & tools

Massively informative thread joybhowmik! Great efforts there!

Even I had made a small step-by-step pictorial guide of the processes involved in dent repair and painting. Because the thread is on the same topic, I'm attaching my link.
Link-http://www.team-bhp.com/forum/mumbai/145323-bodywork-painting-m-motors-borivali-mumbai.html

No intention of hijacking your thread mate! Hope that it adds to the value.
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Old 28th November 2014, 11:12   #29
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Default Re: All about car dent repair & painting - Processes, methods & tools

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Introduction:
You are driving around town in your pristine car, when suddenly, in a fleeting moment your pride & joy is struck! You get out, and staring you in the face is the heart wrenching sight of a beauty in motion - interrupted!
Image courtesy: Google
Attachment 1292945

If you are like most other TBHPians, the sight likely preys on your sensibilities, and correspondingly results in an urge to get it fixed ASAP!

And thus begins a trip to the FNG denter/painter or the main dealer.

In doing so, you happily give in to the monetary demands that they make , trusting in them when they say the magic words:
"whole panel has to be painted",
"at least 3 days of labour",
"Don't worry you won't have to pay anything - we will work it out with the insurance company"
etc.

But has it ever occurred to you , that knowing about common dents and their fix, can help you save $$$? Has it further occurred to you, that the slightest demonstration of knowledge and 'shopping around' can save you even more $$$?

So here's the first tip, which can be easily employed by someone who knows next to nothing about dent/paint shops.
Rule 1: "Shop Around".
If you can Shop Around, when buying a fridge or a TV set or a camera , why not Shop Around when there's a denting/painting job to be done?

This tip alone can save you at least 10% from the most expensive quotation !
joybhowmik, can you please share some info on how to deal with scratches on the matte-finish plastic trim like the one in the below pic. I went to the service center, they body shop guy said they will sand paper it to smoothness and then paint it. But i thought the original texture will be lost and they have to pain the entire length to make it look even.
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All about car dent repair & painting - Processes, methods & tools-img_20141125_212733.jpg  

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Old 28th November 2014, 11:30   #30
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Default Re: All about car dent repair & painting - Processes, methods & tools

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joybhowmik, can you please share some info on how to deal with scratches on the matte-finish plastic trim like the one in the below pic. I went to the service center, they body shop guy said they will sand paper it to smoothness and then paint it. But i thought the original texture will be lost and they have to pain the entire length to make it look even.
The colour is a dark shade, and the scratches don't appear to be very deep or widespread (at least from the picture).
In my view, the cost effective option is to go for a touch up followed by careful application of clear coat on the touched up area, and then buff it back using a good grade polishing compound (3M or equivalent).

When you do the touch up, build up the paint gradually (in layers). Wait 30 mins or so between layers, if the paint is not pre-mixed with hardener.

If you encounter a deep enough scratch - then of course you would need to use filler for that area before you begin the touch up

If you do this well, the 'smudges' will show only on close examination - which should pass for most of the time!

But if you really want the picture perfect look, then am afraid you would need to get the entire panel stripped back to plastic and then repainted. Don't go for any patch work job. By that I mean stripping back the affected area only to plastic, applying filler, and painting it back, with one top-coat on the entire surface.
In time, the top-coat would fade, leaving ugly patchwork visible where the repair was done.


A third option. A tip I picked up from seeing the black plastic bumper covers of Taxi innovas.
Strip back the entire surface to plastic and leave it as it is. Main reason - these are likely stone chip or other damage when parking. Even if you go through the expense of re-painting this - it will come back.

Last edited by joybhowmik : 28th November 2014 at 11:40. Reason: Added third option. :-)
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