# No ptg and compounding first - a warning



## Alex L (Oct 25, 2005)

Just remember Mike Phillips advice, least aggressive product first!

This is my car from 2 years ago, after the batteries went in my PTG.


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## Kimo (Jun 7, 2013)

But junkman says ...


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## pee (Apr 6, 2009)

Kimo said:


> But junkman says ...


Technique trumps product......EVERYTIME :buffer:


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## GleemSpray (Jan 26, 2014)

Is there such a thing as a safe pad + polish combo ? Something which will just clean and brighten up older paint without really cutting or correcting it much.



I have used scratch correction products by hand in small areas and usually use a filling polish by hand, but it would be convenient to have done machine combo that I could safely wizz over the paint with as a starting point clean up - or is that being unrealistic ? Would you just use something like SRP on a machine instead as a time/ effort saver ?



Pls excuse my ignorance....


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## Berylburton (Sep 14, 2013)

Alex L said:


> Just remember Mike Phillips advice, least aggressive product first!
> 
> This is my car from 2 years ago, after the batteries went in my PTG.


Surely it depends on what pads, polish & machine you were using.


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## In House (Dec 3, 2015)

Only high grade one that can read individual layer on the surface can safe us from strike through accident.But they're bloody expensive...


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## Clancy (Jul 21, 2013)

Berylburton said:


> Surely it depends on what pads, polish & machine you were using.


Think that's the point he's making, start from the bottom and work up

Don't just jump into heavy combinations because someone said so when there are more variable involved than usually mentioned


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## Alex L (Oct 25, 2005)

Clancy said:


> Think that's the point he's making, start from the bottom and work up
> 
> Don't just jump into heavy combinations because someone said so when there are more variable involved than usually mentioned


Exactly, this instance was wetsanding and scholl s3 on a rotary. But don't think you can only do damage with the rotary.

From memory, it was Mike Phillips or L200 Steve that said somewhere that the edges of a DA used pad spin faster than a rotary, so have the ability to heat up and burn through paint quicker.

This will probably end up like any safety thread, but please try the softest option first. All these youtube teachers are great, but they don't know what the paint is like you're working on and I'm positive that if you stuff it up following their videos they wont offer to help pay to get it repaired. No matter how much you followed their instructions to the letter.


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## Alex L (Oct 25, 2005)

pee said:


> Technique trumps product......EVERYTIME :buffer:


Exactly, and the best technique is to start soft and work up. Not jump straight to compound like some recommend.


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## cheekymonkey (Mar 15, 2008)

GleemSpray said:


> Is there such a thing as a safe pad + polish combo ? Something which will just clean and brighten up older paint without really cutting or correcting it much.
> 
> I have used scratch correction products by hand in small areas and usually use a filling polish by hand, but it would be convenient to have done machine combo that I could safely wizz over the paint with as a starting point clean up - or is that being unrealistic ? Would you just use something like SRP on a machine instead as a time/ effort saver ?
> 
> Pls excuse my ignorance....


You can use a pre wax cleaner for that or if you are cleaning the paint as a start, a paint cleaner would be better.


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## nick_mcuk (Jan 4, 2008)

In House said:


> Only high grade one that can read individual layer on the surface can safe us from strike through accident.But they're bloody expensive...


Exactly....unless you spend big dolla on a PDG that will give you the break down of each layers thickness the very very large majority of these PDG are pretty much useless...especially as some of them don't even work on painted plastic surfaces!


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## Alex L (Oct 25, 2005)

nick_mcuk said:


> Exactly....unless you spend big dolla on a PDG that will give you the break down of each layers thickness the very very large majority of these PDG are pretty much useless...especially as some of them don't even work on painted plastic surfaces!


And not an exact science, but a general rule of thumb is to measure the door shuts as they have less clearcoat than exterior panels.

As for plastics, buy an old car with chrome bumpers


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## nick_mcuk (Jan 4, 2008)

Alex L said:


> And not an exact science, but a general rule of thumb is to measure the door shuts as they have less clearcoat than exterior panels.
> 
> As for plastics, buy an old car with chrome bumpers


So still leaving a guessing game and basically a complete waste of money.

I go back to my point...unless you are going to buy a unit that measures and tells you the thickness of each layer dont bother with it.


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## Alex L (Oct 25, 2005)

Some measurements are better than going in blind and hoping for the best.

But I do agree many people have done perfectly fine with out them for years, by starting light and working up.


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## nick_mcuk (Jan 4, 2008)

Alex L said:


> Some measurements are better than going in blind and hoping for the best.
> 
> But I do agree many people have done perfectly fine with out them for years, by starting light and working up.


Yep that's always worked for me.


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## Big Buffer (Jan 1, 2011)

All very good information and if u have a budget for a ptg, just for extra pea e of mind it's worth it. Not everyone opinion I know but it's your own. 

As already mentioned tho lowest pad and Polish combo to start and work up slowly.

Plenty of advice here for anyone to find and more than enough guys to help with answers


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## Alex L (Oct 25, 2005)

Big Buffer said:


> All very good information and if u have a budget for a ptg, just for extra pea e of mind it's worth it. Not everyone opinion I know but it's your own.
> 
> As already mentioned tho lowest pad and Polish combo to start and work up slowly.
> 
> Plenty of advice here for anyone to find and more than enough guys to help with answers


The thing is, you'd think common sense would prevail. But you get one 'expert' saying one thing and another 'expert' saying another, it can become quite confusing for beginners.


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## justina3 (Jan 11, 2008)

Alex L said:


> The thing is, you'd think common sense would prevail. But you get one 'expert' saying one thing and another 'expert' saying another, it can become quite confusing for beginners.


confusing thats an understatement :thumb: people often ask me when they see a machine in my hand how do i do that and where do i start ? my answer is always the same go get a few scrap panels and practice practice and more practice


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## GleemSpray (Jan 26, 2014)

Before you attack any paintwork, remember that 100 microns is merely one tenth of one millimetre.


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## sm81 (May 14, 2011)

How thin you can go? If I have door sills 60micro and bonnet 90?


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## MAXI-MILAN (Oct 26, 2008)

GleemSpray said:


> Is there such a thing as a safe pad + polish combo ? Something which will just clean and brighten up older paint without really cutting or correcting it much.
> 
> I have used scratch correction products by hand in small areas and usually use a filling polish by hand, but it would be convenient to have done machine combo that I could safely wizz over the paint with as a starting point clean up - or is that being unrealistic ? Would you just use something like SRP on a machine instead as a time/ effort saver ?
> 
> Pls excuse my ignorance....


SN Micro Prime or DJ BOB Prep Polish by LC white polishing pad or 3m yellow polishing pad , I used Micro Prime in old Toytoa land Crusier 2000 the paint in very bad condition looks like there is no clear coat , the result of PTG is 45 um :doublesho I used SN Micro Prime it gives great result :thumb: also I used PA Master Compund with 3M polishing pad with light pressure in some areas :thumb:


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## nick_mcuk (Jan 4, 2008)

sm81 said:


> How thin you can go? If I have door sills 60micro and bonnet 90?


...and that illustrates the point...unless you have the mega bucks PDG you are still guessing.

Ok so you have 60microns on the door shuts and 90 on the bonnet but you still have absolutely no idea oh how much lacquer is on there?


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## sm81 (May 14, 2011)

I can guess that 10-20 microns


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## turbosnoop (Apr 14, 2015)

I dont have a ptg, and, this might sound insane to some, but if my paint was that swirled up that I felt the need to get the da out, and using my usual combo of m205 and a white pad I was to breakthrough anywhere , my attitude is that I'd rather just pay for respray work where needed.
If its between that and living with messed up swirly paint on my pride and joy, that I was too scared to polish as it was very thin, I'd rather polish it, the worst that happens is it goes to a bodyshop.
So in fact for myself and anyone who thinks like me and works on there own car, then a ptg is a waste of time.


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## nick_mcuk (Jan 4, 2008)

turbosnoop said:


> I dont have a ptg, and, this might sound insane to some, but if my paint was that swirled up that I felt the need to get the da out, and using my usual combo of m205 and a white pad I was to breakthrough anywhere , my attitude is that I'd rather just pay for respray work where needed.
> If its between that and living with messed up swirly paint on my pride and joy, that I was too scared to polish as it was very thin, I'd rather polish it, the worst that happens is it goes to a bodyshop.
> So in fact for myself and anyone who thinks like me and works on there own car, then a ptg is a waste of time.


Top marks...100% agree!

In all the years i have been detailing I have only polished through 3 times and none of them were in the middle of a panel they were all edges....touched in and all done.


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## nick_mcuk (Jan 4, 2008)

sm81 said:


> I can guess that 10-20 microns


exactly you are guessing you dont actually know....


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## cheekymonkey (Mar 15, 2008)

nick_mcuk said:


> exactly you are guessing you dont actually know....


actually thats not a guess just simple mathematics. 60 on door shut including some clear coat, and 90 on bonnett = 30 difference. so take 20 off still leaves 10 more than on the shut. That is much more knowledge then closing your eyes , praying and turning the machine on


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## cheekymonkey (Mar 15, 2008)

turbosnoop said:


> I dont have a ptg, and, this might sound insane to some, but if my paint was that swirled up that I felt the need to get the da out, and using my usual combo of m205 and a white pad I was to breakthrough anywhere , my attitude is that I'd rather just pay for respray work where needed.
> If its between that and living with messed up swirly paint on my pride and joy, that I was too scared to polish as it was very thin, I'd rather polish it, the worst that happens is it goes to a bodyshop.
> So in fact for myself and anyone who thinks like me and works on there own car, then a ptg is a waste of time.


a £100 ptg would of saved that respray:thumb:


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## cheekymonkey (Mar 15, 2008)

nick_mcuk said:


> Top marks...100% agree!
> 
> In all the years i have been detailing I have only polished through 3 times and none of them were in the middle of a panel they were all edges....touched in and all done.


In over 25 years i have never blown through, i put that down to my ptg. Still have my first one, that worked with a magnet. 3 resprays would cost a lot more than i have spent on PTG's. no embarrassment either


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## nick_mcuk (Jan 4, 2008)

cheekymonkey said:


> actually thats not a guess just simple mathematics. 60 on door shut including some clear coat, and 90 on bonnett = 30 difference. so take 20 off still leaves 10 more than on the shut. That is much more knowledge then closing your eyes , praying and turning the machine on


Still a guess you dont know if there is 5 microns or 50 of clear there.....your just making an assumption and we all know what assumptions do!


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## cheekymonkey (Mar 15, 2008)

nick_mcuk said:


> Still a guess you dont know if there is 5 microns or 50 of clear there.....your just making an assumption and we all know what assumptions do!


well them assumptions have stopped me ever blowing through, unlike your cavalier way of not bothering at all. If you are happy having to have cars resprayed due to ignorance then that is your choice. PDG (used properly) gives you more insight and knowledge of the paint before polishing.That knowledge stops you ruining paint


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## nick_mcuk (Jan 4, 2008)

Nothing cavalier as you put it with my methods in the 19 odd years I have been correcting and polishing paint with a rotary (or MOP which is the correct terminology) I have only ever polished through a finish 3 times as said and those were all less than 1cm and on an edge which everyone learns are notoriously thin, oh and 2 of those times were on a practice panels and the 3rd time was on a completely FUBAR car that a dealer wanted "made shiny"

If you spend enough time practicing and learning about paint and how to read the finish you don't need a PDG, especially not one that just gives you an overall reading that still leaves you making guesses on what thickness is there. To me that is more cavalier as you are guessing and have not inspected and learned to assess the paint correctly. 

I have run my own sideline business doing detailing and Valeting and had hundreds of happy customers and have corrected and refined the finishes on their cars without the use of a PDG. I also know a number of top detailers that also don't use a PDG and have never had issues or destroyed a finish. 

I think your attitude and response is similar to someone doing a review of a high end big price wax they have purchased. You feel you have to justify the item because you have spent big money on it. 


Sent from my iPhone using Tapatalk


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## cheekymonkey (Mar 15, 2008)

nick_mcuk said:


> Nothing cavalier as you put it with my methods in the 19 odd years I have been correcting and polishing paint with a rotary (or MOP which is the correct terminology) I have only ever polished through a finish 3 times as said and those were all less than 1cm and on an edge which everyone learns are notoriously thin, oh and 2 of those times were on a practice panels and the 3rd time was on a completely FUBAR car that a dealer wanted "made shiny"
> 
> If you spend enough time practicing and learning about paint and how to read the finish you don't need a PDG, especially not one that just gives you an overall reading that still leaves you making guesses on what thickness is there. To me that is more cavalier as you are guessing and have not inspected and learned to assess the paint correctly.
> 
> ...


I dont and wont justify to you or anyone else what i spend my money on, i buy what i believe is helpful and A ptg is an essential tool and a big reason why i have never blown through. the ptg was a lot less then a paint repair and has actually saved me money
When machining ( mop actually comes from refinishers not detailing) my own or anyone elses paint it is my responsibility to know as much about the paint before i start. 
I know and understand all about knowing and assessing the paint, but add to that the use of a PTG and you are even more aware of what you are up against, as long as you use the ptg right. I dont just mean a couple of readings hear and there. .there are plenty of places where you can get helpful reading. such as behind rear lights or under window/ windscreen rubbers and under gutter plastic. 
with a ptg you can also draw a overall picture of each car paint you use it on. Take the readings before you polish and after and note the condition of the paint and polishes used to repair the paint. then you know how much paint was removed to correct the noted damage. the next time that car comes i have all the history of all paint readings, what correction was done with what polish and compounds and the amount of paint removed to correct it. Imo if you are working on other peoples cars it is of a cavalier attitude not to use a PTG and as you say you have blown through 3 times, a PTG used properly would of stopped that.


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## nick_mcuk (Jan 4, 2008)

I don't disagree a PROPER PDG would be of use...by proper I mean one that breaks down the layers and tells you exactly whats what. One that gives you an overall reading is ok to show if a panel has been repaired etc but it absolutely non use in telling you how much you can polish a panel as you are still guessing about the thickness of the clear coat....oh and what if its a single stage paint job on an older car thats been painted/repaired a few times....lots of guess work there going on with your overall readings?

Not to mention the lack of readings you will be getting from the non ferrous parts of the car....what do you do there guess or just leave them alone because its "too cavalier" to polish a car without a PDG?

I am going to leave it there....


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## Mugwump (Feb 17, 2008)

nick_mcuk said:


> ....unless you spend big dolla on a PDG that will give you the break down of each layers thickness the very very large majority of these PDG are pretty much useless...!


The real point of a basic PDG is not so much to tell you how much is there to start with, but rather more to tell you how much you have removed - it still leaves an element of guesswork based on the assumption you make about the percentage of the total which is clearcoat, but it is a whole lot better than working totally blind.

As most of us can neither afford nor justify the cost of a PDG that will sense the different layers, a basic total depth type is a massive help, and for less than the probable cost of a panel respray to rectify strike through damage, I think you would need a very good reason to not use one??

Yes, plastic/GRP panels are a problem, but that is no reason not to use one on the rest of the vehicle. You just need to be cautious on the non metal parts.


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## cheekymonkey (Mar 15, 2008)

nick_mcuk said:


> I don't disagree a PROPER PDG would be of use...by proper I mean one that breaks down the layers and tells you exactly whats what. One that gives you an overall reading is ok to show if a panel has been repaired etc but it absolutely non use in telling you how much you can polish a panel as you are still guessing about the thickness of the clear coat....oh and what if its a single stage paint job on an older car thats been painted/repaired a few times....lots of guess work there going on with your overall readings?
> 
> Not to mention the lack of readings you will be getting from the non ferrous parts of the car....what do you do there guess or just leave them alone because its "too cavalier" to polish a car without a PDG?
> 
> I am going to leave it there....


there is far less guess work with a ptg then without, infact used properly the guess work is removed. Yes the expensive ones are better but even a basic is far better than none. 
Doesn,t matter what the state of the paint or how many resprays its had . You will still know more about it with a basic ptg then without. 
As you said your self you have had hundreds of customers, that works out at well under a £1 a car for a ptg which would of stopped you blowing those 3 times. You claim you know just as much without a ptg as you would with, so how thick is your paint?


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