# HELP - My first detailing mistake?



## SCZ4 (Feb 1, 2009)

Guys,

Need your advice as I've screwed up my mates car and feel terrible  This evening I was helping to remove a long and fairly deep scratch from my mates BMW M135i with my DAS6 dual action polisher. After speaking to Spautopia, I bought a Spautopia Spider Sandwich 80mm Pad and Spautopia S3 Edition Gold for the job. For info, I've done a full detail of my old S2000 and removed scratched from my 5 series and other cars without any problems, but these specific products are new to me.

All was going well, the scratch was slowly disappearing. But then I polished off the residue to reveal this  (you can judge the size of looking at the fuel cover\flap)





Just to go over what I did. I started by washing the area and dried. Sprayed some detailer on the pad and applied the S3 polish\compound. Smudged the polish onto the paint then worked it around on speed 2 our out of 6. I then increased the speed to 4 and worked the area for around a minute or so. I then wiped off the polish. I repeated the process, but on speed 5. Again, absolutely no problems. Results were promising, so got back on it, same process, but the above happened. I doesn't feel any rougher to the nail, but does sound slightly different.

How can\do I resolve this? I tried a hand polish for a few seconds as I was scared to try anything else, but no joy. Please don't flame me, feel s**t enough.... looking for constructive help.

G


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## rf860 (Jul 24, 2011)

Looks like you've gone through mate. Feel for you though, nothing worse than damaging somebody else's property


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## SCZ4 (Feb 1, 2009)

Really!! The lacquer I assume? 

It's hard paint though.. When I was talking to Spautopia they were emphasising how hard I'd have to work it and weren't even sure it would make an impact. 

Could it be because the car\paint is only 4 months old.


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## SCZ4 (Feb 1, 2009)




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## danwel (Feb 18, 2007)

As above looks very much like you've gone through and only a re spray will fix it


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## suspal (Dec 29, 2011)

Did you take any paint depth reading's? that a respray mate


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## nick.s (Dec 21, 2009)

Looks very much like strike through fella  As others have said, respray required I'm afraid chap.


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## SCZ4 (Feb 1, 2009)

suspal said:


> Did you take any paint depth reading's? that a respray mate


No I didn't. Don't have one. It's a brand new car.


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## SCZ4 (Feb 1, 2009)

I just don't get it  Wonder if the 1 series has soft paint and the pad\compound was too aggressive? Never had any problems before.


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## SCZ4 (Feb 1, 2009)

Here's what I was advised

"For general weathering on most paints we would normally recommend Scholl Concepts S17+, however you will probably find that the paint on your BMW is extremely hard so Scholl Concepts S3 Gold on the Scholl Concepts Spider Sandwich Pad (on a DAS-6) would be a better combination. *You will need to work it lots due to the paint hardness.*

For finishing we would recommend Scholl Concepts S30+ on the Scholl Concepts Orange Pad and, likewise, *be prepared to work it well to get the result your desire.*"


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## rf860 (Jul 24, 2011)

SCZ4 said:


> I just don't get it  Wonder if the 1 series has soft paint and the padcompound was too aggressive? Never had any problems before.


Doesn't matter if it's new or not. Paint thickness is paint thickness, it doesn't thin out over time.

I think probably a harsh compound and pad has caused it.


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## ianrobbo1 (Feb 13, 2007)

As above, looking like the old strike through to me as well, 

for future reference if your new to the paint/car, always start soft, before going to the big guns, less likelihood of this happening again!!

hope your mate is OK with it/you, and you can sort it out for him soon!!


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## turboyamaha (Nov 18, 2010)

Bad luck mate hope you get it sorted!


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## Kimo (Jun 7, 2013)

Yup, strike through meaning a respray 

Sounds like you only worked that small area for the whole time with too aggressive products :/


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## NipponShine (Jun 19, 2012)

feel sorry for you, and worst it belongs to your friends, maybe you apply excessive force on high speed and letting it idle in the same place too long?


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## cole_scirocco (Mar 5, 2012)

Ouch mate!

Feel terrible for you I really do. Hope you and the car owner sort it out okay though!


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## SCZ4 (Feb 1, 2009)

Thanks for the feedback and sympathy guys! Not looking forward to that phone call. 

The frustrating part is to completely remove the scratch would of required a respray regardless as one section was really deep, but we could of got it looking 90% without the need for a respray, just leaving a small 1cm section.


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## seaneyb (Mar 26, 2009)

You could get away with a smart repair specialist which will cost less than a full body repair. 

Sorry to hear your bad luck. Just be careful in the future. Lots of good tips detailing tips have already been given. I always say least aggressive polish and pad combo first. If that doesn't work try a different pad same polish and if necessary go 1 stage up on the polish.


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## norfolk_msd (Nov 18, 2013)

Feel for you chap, we all make mistakes. Are there any sprayers on here to help out? Where in uk are you?


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## xJay1337 (Jul 20, 2012)

Your biggest mistake is jumping straight in!! Always work with the least aggressive compound necessary!!!!! This should be basic knowledge especially if you have worked on cars before.

Everyone saying get a PTG, this doesn't help. Buy a PD8 and it says 120 microns, cool, how much of that is clear coat? You don't care how thick the PAINT is you care how thick the clearcoat is.
I can see the benefits of having one vs not having one to simply have a ROUGH idea but it's not accurate.
I would never work an area that small for a whole minute, to be honest it was waiting to happen.


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## stangalang (Nov 27, 2009)

Few points from me, or thoughts rather. Spider sandwich pad on a das6? IMO that isn't the best combo, those pads are not very good on a random orbital, again just my opinion. Did you move the pad around, or did you just hold it in pretty much one spot? The thing with those pads, and that polish, is it is very aggressive, which you knew, but it designed to be moved around, so the smaller the pad the smaller the work area, but not just over an area the size of your pad (i hope that makes sense). Remember with an RO, the smaller the pad the HIGHER the cut, its the opposite with a rotary, and as they are aggressive putting a lot of pressure on would produce a lot of cut indeed. 3 hits could remove a fair old amount of clear coat in 3 to 5 minutes. 

LASTLY, and this is the problems with forums imo, its easy for people to dish out their fact nuggets, but there is no accountability there after, I've seen some horrific advice given and you know full well the giver won't pay for a respray if it goes bad, so its all on you. Best way is to always start with a weak combo, assess the results, did it make an improvement? Will a second hit remove it? If so its sometimes safer to do more sets instead of stepping up product harshness. Build a picture in your mind, use as many tools as you can, your eyes, your ears, a paint gauge, owners intimate knowledge. All of this together gives you a history and story, gives you an idea of clear thicknesses, an idea of possible repairs etc etc etc. All this will determine how you work with the car. 

Unfortunately you and your friend have paid the price, but don't be put off permanently, just breathe, think, and take extra time next time, try to enjoy it and learn something each time. It is after all, meant to be fun


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## Jem (Aug 10, 2007)

xJay1337 said:


> Your biggest mistake is jumping straight in!! Always work with the least aggressive compound necessary!!!!!


I don't this this was the problem here, as after two hits the scratch was still there.

I think it's more a case of inexperience leading to not knowing if a scratch is too deep to remove or not.


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## jamie_s (Jul 10, 2009)

Jem said:


> I don't this this was the problem here, as after two hits the scratch was still there.
> 
> I think it's more a case of inexperience leading to not knowing if a scratch is too deep to remove or not.


Exactly what I was thinking. The problem was the scratch was too deep to fully remove not that the combo was too harsh. If he struck through on the first hit yes but he didn't. I feel for you mate I always tend to improve a deep scratch rather than remove it because I'm scared of this happening. A paint thickness guage would be brilliant for this sort of thing they're just so damn expensive :/


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## nichol4s (Jun 16, 2012)

Live and learn buddy, it's irrelevant what you were advised I.e bmw paint is hard, soft or even still wet as it was brand new it could have had paint already it could have been machined already too no amount of polishing will bring this back it may just make it worse this is 

1. Why you should have a ptg
2. Start with a lesser combo
3. Leave it to the pro's who are insured for such circumstances.

Thing to do now IMO is go cap in hand to you friend and get it sorted out and leave scratch removal to someone else.

All the best


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## V3nom (Oct 31, 2012)

This is why I have never previously offered to do 'scratch removal / correction' for friends. I only recently got a PTG and without one, I'd never go so harsh.

As said, we all make mistakes but start off lighter next time


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## SCZ4 (Feb 1, 2009)

Thanks again all... oh and yes I was moving the pad around constantly. 

I'm still not sure a thickness gauge would of helped in this situation. It may to someone with more experience and can calculate how aggressive that pad and polish combination can be. 

So to sum it up:

- Despite professional advice, I've picked a pad and compound too aggressive and should of started of with a lighter cut. 
- Misjudged how deep the the scratch. Probably not repairable by machine. 
- Don't work on mates cars....


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## suspal (Dec 29, 2011)

You sometime have to resign yourself and say I'm going to have to leave that scratch just got to live with it,It's one of them Stangalang has put It across very well :thumb:


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## Clyde (Feb 15, 2012)

Gutted for you mate, but treat it as a learning curve. It would prob put me off doing anyone elses car for a while but I'm sure in time you get over that


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## xJay1337 (Jul 20, 2012)

Jem said:


> I don't this this was the problem here, as after two hits the scratch was still there.
> 
> I think it's more a case of inexperience leading to not knowing if a scratch is too deep to remove or not.


As you say exactly, it's about knowing what you can get out and what you can't get out.

The most important thing as a detailer is knowing WHEN to stop.


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## richard56 (Sep 29, 2013)

Everyone makes mistakes, it is a part of learning. I bet everyone on this forum has ****ed up at sometime. Not necessarily while detailing.
You may beat yourself up for a time but you will get over it.
You have gained some invaluable experience.
I hope all goes well for you in the future.


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## muzzer (Feb 13, 2011)

I havent gone near my car with my DA yet but even though i have a practice panel, i watch The Junkman's How to Machine Polish videos over and over to get an idea and as has been said by people more experienced than me, and by the junkman, start at the leadt agressive end and work your way up as and when you need to.

As to your mates car, try Chips Away(is that their name?) might be the cheapest way to fix it.


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## ABC Detailing (Jun 29, 2010)

SCZ4 said:


> Thanks again all... oh and yes I was moving the pad around constantly.
> 
> I'm still not sure a thickness gauge would of helped in this situation. It may to someone with more experience and can calculate how aggressive that pad and polish combination can be.
> 
> ...


Really feel for you mate, but you seem to have quickly learnt to step back and assess cars on an individual basis, regardless of preconceptions of paint hardness and thickness.

I wouldn't discourage working on friends' cars at all, it's a good job it's not a stranger who may take you to court for being uninsured!


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## Jem (Aug 10, 2007)

SCZ4 said:


> I've picked a pad and compound too aggressive and should of started of with a lighter cut.
> - Misjudged how deep the the scratch. Probably not repairable by machine


I don't think it was too aggressive. You said it was on the third hit that you went through. So for example, say the car had 50 microns of clear coat and the scratch was 55 microns deep. The first hit may have taken 20 microns off, leaving with with 30 microns of clear coat, the second hit may have taken another 20 microns, leaving only 10 microns, but you can still see the scratch, so you go with another hit, take another 20 microns off and are left with a strike through.

With a milder polish/pad, you may have been taking 15 microns off with each hit, so by the end of the third hot you'd have removed 45 microns, but would still have seen the scratch, so thinking it's a milder polish, go for a forth hit and still strike through.

A paint thickness gauge would have helped, as it would have given you an idea of just how much paint there was to start with, if it's been polished before and how much paint you're removing. Bear in mind that the paint expands with heat, so take a reading of 100um on cold paint, polish the paint, removing 2 microns but getting the paint warm, the hot reading will could be 105 microns, let the panel cool, the paint will contract and you'll get a true reading of 98um.

A paint thickness gauge is not a guarantee you won't strike through, but it does give you a much better idea of how much paint you have to play with, and how much you are actually removing.

But most importantly, don't be discouraged, we all make mistakes, get back up, brush yourself down and learn from it :thumbs:


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## danwel (Feb 18, 2007)

Sound advice from Matt aka Stangalang.

I've spent ages reading on here and had some hands on advice from Matt while he was up my way and the main thing i found and it is not a go at people on here is that you really need to be realsitic as to what you can avhieve. Some of the reuslts you see on here from touch up stone chips using paint and wet sanding look amazing and you would never tell however in reality to the amateur it is very difficult to actually achieve perfection so sometimes you have to accept that perfection is not an option and that some of the repairs and attempts at scratch and swirl removal will only be up to an acceptable standard.

just from my own experiences i had a go on my door at a couple of stone chips that left dents and i always planned on getting it resprayed professionally but i had a go at paint and wet sanding and in my attempts for perfection after seeing how easy people make it look on here i soon went through the clear coat.


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## Tom J (Mar 29, 2009)

At the end of the day mate, if the scratch was that bad he'd have needed a re spray anyway. You tried your best he should understand if he's a good mate


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## S4Steve (May 9, 2013)

If he wanted the scratch removed one way or another (and not just reduced) then I'm thinking the respray would be needed regardless as it was clearly too deep? Live and learn mate, don't worry!


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## deano93tid (May 8, 2013)

I feel for you. 

A lot of great advice already here. I disagree with the idea of the PTG being no use to you, you have made a mistake and now you will be cautious and now know much more than you did prior to making the mistake. 

I know with the cheaper PTG's you cannot determine the exact amount of clear but it gives you an idea if the car has had a respray at any point, if there's a lot less in areas then chances are it has been polished in a local area previously, you can look online for information about specific car paints. The most important thing about the gauge is it can show you what you are removing, this is what you need to know. Roughly a third of the reading is the clear so 100 would be 33.33333 of base, colour and clear. (I say roughly, the clear can be a lot more but always edge on the side of caution). You can always remove more but you can't put it back on.


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## ITSonlyREECE (Jun 10, 2012)

Ouch! I definitely agree with the people who've said about if the scratch was that deep your mate would've definitely needed a re-spray regardless of whether you went through the lacquer or not.

Don't beat yourself up over it, mistakes happen. It's just lucky that this mishap happened on a task which needed a re-spray anyway. If anything you've done the painter a favour by getting the scratch out for him lol


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## xJay1337 (Jul 20, 2012)

deano93tid said:


> I know with the cheaper PTG's you cannot determine the exact amount of clear but it gives you an idea if the car has had a respray at any point, if there's a lot less in areas then chances are it has been polished in a local area previously, you can look online for information about specific car paints. The most important thing about the gauge is it can show you what you are removing, this is what you need to know. Roughly a third of the reading is the clear so 100 would be 33.33333 of base, colour and clear. (I say roughly, the clear can be a lot more but always edge on the side of caution). You can always remove more but you can't put it back on.


That's not really true at all.
Wet sanded my Merc AMG Aero 2 faces after powdercoating. They measured over 350microns and had only been painted a few days prior so no prior machining.
One burnt through with about 330 microns showing.

It can give you a good idea however people can get lulled into a false sense of security with a gauge. 
I know of some details who swear by them and some who hate them, I can see both sides really


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## Andy from Sandy (May 6, 2011)

On my car there is areas that have minimal to no clear coat so if I check in that area first with a PTG I will get a better idea of how thick the clear coat is when I check a panel.

So by starting with the least aggressive setup you do a set and then check how much clear coat was removed and also what effect did it have on the defects you are trying to remove. If nothing was removed then step up a grade of polish or cut of pad and try again.

The idea of stepping up in polish grade and pad cutting power in my opinion is all about getting the job done to a particular time frame. If you have all the time in the world you can carry on with what you are doing taking tiny amounts at a time.

Everyone is generally well meaning but unless the car has been assessed in person and actually done any polishing it is no good anyone telling you how hard the paint is or what polish and pad should be used.


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## Flakey (May 5, 2013)

Stangalang has put it brilliantly. I cut through the clear recently on my bike and looking back, I asked for it. Being a newbie and no previous experience with wool pads; I hit a deep scratch with a 8" wool pad and M105 and put lot of pressure on it. Just like the OP, worked it for a minute in one spot. Once I was done, there was paint all over the pad. However, it was a good lesson for me. I have now changed my approach to start with the least aggressive polish and pad and then try the same polish on more aggressive pads before moving up to a more aggressive polish. I was planning to do Hyper Compound + P85Rd as a two step correction on my car but now I plan to try P85RD with at least two sets of pads before probably moving up to a medium cut polish like Scholl S20. 

All of us make mistakes and read about taking the least aggressive approach but we need to STICK to that method always. Especially, when we are uncertain about the variables like paint thickness, hard/soft paint, new pads or new polish at hand.


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## Tricky Red (Mar 3, 2007)

You live and learn. Just because BMW paint is classically harder than most, does not imply all are the same. I understand even the colour of paint can change the hardness as odd as that sounds. 

I would have used a gauge on this but, then again I have one. Would I have bought one purely for this job... probably not. 

You made a mistake, that's all. Your mate might not be happy but he's your mate and he should understand.


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## Big Buffer (Jan 1, 2011)

Some of the newer german paints are softer than older ones. You have learned from it at a cost but still valuable to yourself. 

We allake mistakes buddy dont beat yourself up too much.


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## Clark @ PB (Mar 1, 2006)

xJay1337 said:


> That's not really true at all.
> Wet sanded my Merc AMG Aero 2 faces after powdercoating. They measured over 350microns and had only been painted a few days prior so no prior machining.
> One burnt through with about 330 microns showing.
> 
> ...


Did you burn the top coat or go through it? Two different things.

And I find it strange that a detailer would hate a PTG! If someone drops in past us for a quote on a localised scratch repair then the first thing I do is reach for the gauge.


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## tigercub (Jan 1, 2014)

I have contacted BMW as I own a mini and was concerned about the thickness of the paint on some new BMW cars and the mini as it's getting thinner and thinner.although it's hard paint they said they don't use primer anymore which reduces the thickness of the paint not sure how this effects the thickness of what's left but I'm always careful due to new paintwork being thinner. My mini is new and has 80 microns of paint. Not much I dint think.


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## tigercub (Jan 1, 2014)

Agree see if you can get a smart repair and with out being unreasonable the bodywork was scratched and needed to be repaired anyway. I know this doesn't make it feel any better. Good luck mate. Must feel terrible


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## Andy from Sandy (May 6, 2011)

> My mini is new and has 80 microns of paint. Not much I dint think.


With no primer coat is 40 + 40 good or bad?


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## tigercub (Jan 1, 2014)

Well most cars have between 80/140 microns I am told so my car is at the low end of the scale. Maybe the amount of clear coat.and base coat is the same as other cars? But you still get a low reading as no primer.


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## Sick_at_Sea (Dec 14, 2013)

That's put me off buying a rotory or a DA!


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## tigercub (Jan 1, 2014)

My mates BMW is about the same some areas down to 76 microns and it's never been polished it's a 63 plate.


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## suspal (Dec 29, 2011)

My mini is new and has 80 microns of paint. Not much I dint think.

This explains the process why :thumb:

http://www.pfonline.com/articles/waterborne-painting-process-is-a-first-at-south-carolina-bmw-plant


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## tigercub (Jan 1, 2014)

suspal said:


> My mini is new and has 80 microns of paint. Not much I dint think.
> 
> This explains the process why :thumb:
> 
> http://www.pfonline.com/articles/waterborne-painting-process-is-a-first-at-south-carolina-bmw-plant


Yeah I have read about it. Saves time and money better for the environment I suppose. All manufacturers will be doing the same. :thumb:


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## Andy from Sandy (May 6, 2011)

So that suggests a colour coat without a clear on top just a durable colour coat.


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## tigercub (Jan 1, 2014)

Andy from Sandy said:


> So that suggests a colour coat without a clear on top just a durable colour coat.


I suppose so. I'm very careful with my paint now I never use anything abrasive unless I really have to and I take great care in preserving my swirl free paint work so I don't have too. :thumb:


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## tigercub (Jan 1, 2014)

Sick_at_Sea said:


> That's put me off buying a rotory or a DA!


Don't let it put you off. Suggest you just buy a coating depth gauge first or at the same time. I wouldn't use a Da and definitely not a rotary with out one :thumb:


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## mbgti01 (Feb 19, 2013)

Gutted for you mate


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## graham1970 (Oct 7, 2012)

The one thing you can't learn from vids,books and internet is experiance....hope everything works out for you and your mate 'fella.


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## herbiedacious (Sep 27, 2010)

That's a tough break, especially as you were only trying to do a favour for a mate. I hope he is ok about it. If it's any consolation, the fact that you have had the guts to write this post might well prevent others from making the same mistake. Hope it works out for you.


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## deano93tid (May 8, 2013)

tigercub said:


> I have contacted BMW as I own a mini and was concerned about the thickness of the paint on some new BMW cars and the mini as it's getting thinner and thinner.although it's hard paint they said they don't use primer anymore which reduces the thickness of the paint not sure how this effects the thickness of what's left but I'm always careful due to new paintwork being thinner. My mini is new and has 80 microns of paint. Not much I dint think.


Mines on an 08 and it's 200+ all over :-s sound about right?


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## Clark @ PB (Mar 1, 2006)

We've done 3 x 2013 Mini GP Works and they were all showing readings of anything from 55-110-ish microns. Even on the areas of 70 or 80 I was getting split layer readings of around 25-30 for the top coat. 

One of them was in the 200's down the drivers side which I informed the owner of. Turns out there was some sort of incident at the factory and it was re painted apparently.


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## xJay1337 (Jul 20, 2012)

I'd probably get my brand car taken to have extra clear coat applied...


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## Mat page (Jan 10, 2014)

Always use a pdg if you can. Take measurements throughout. I feel your pain :/


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## Stezz (Apr 29, 2011)

Ouch!

As long as your mate is happy that you will get it sorted, don't let this put you off.

In truth, I've gone through the paint on my old Jag even with a PDG. I took 5 readings per panel but still managed to go through.


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## stiffler69 (Jan 20, 2014)

Had similar recently myself luckily the car and panel I was working needed paint anyway scratches where beyond repair, however I literally got strike through with the first pass, well lubricated area with lots of movement. This was on a BMW also all be it a much older BMW and in a area where the paint would of worn thin from constant rubbing from hands etc as it was just below the door handle.


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## xJay1337 (Jul 20, 2012)

Stezz said:


> Ouch!
> 
> As long as your mate is happy that you will get it sorted, don't let this put you off.
> 
> In truth, I've gone through the paint on my old Jag even with a PDG. I took 5 readings per panel but still managed to go through.


PDG only will show you total paint depth which is useless for a machine correction. As you have proven they're pretty pointless.. it's good for gauging removal rates and telling for sure if a panel has been resprayed before and thus require different kind of care.


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## AllenF (Aug 20, 2012)

Ouch that hurts.
But a valuble lesson there youwont do that again in a hurry will you?
As for ptg being useless..... Mmmmm each to there own. They give you a guide to the depth of paint. If you are stupid enough to take a reading and then divide it by two and reckon you can take 50% of that away,.... 
Shakes head woefully. If you read davekdg' s guide im fairly certain he tells you that its NOT a simple divide by three number i personally take a reading and only bank on about 15- 20% to be clear so on an 80Um reading the absolute MAX i would dream of taking off would be 16Um but more than likely only 4Um to ensure i leave plenty of meat. A mark deeper than that and it would be spot worked until i have either removed it or got down to my set max removal limit.
Been machining over 20years and have only ever gone through on purpose to prove a point. And yes i ave gone through by hand as well to prove that can be done too.
K rant over.
A smart repair should cover that up ok. ( or put a sticker over it???) every days a school day.


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