# How many times can you machine polish a car?



## MA3RC (Jun 19, 2012)

I know this is a very very vague question and there will be many different responses and would ideally require a paint gauge but....

If you had a brand new car, how many light to moderate corrections on the car could you perform before striking through?

I'm only after an estimate out of curiosity more than anything

Thanks


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## -Kev- (Oct 30, 2007)

seven 










seriously though, it's really not easy to say without a PTG (which will only give you a reading for the full paint thickness, rather than just the clear coat..). then again, if it's brand new and if the dealer leaves it alone, would it ever really need machine polishing if you're careful enough when washing it?.. 
a finishing pad + polish once a year would be ok i should think


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## Silky-cookie (Nov 19, 2012)

good question, i'd be interested in this too....one of those randoms you never think to ask until someone does


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## Guitarjon (Jul 13, 2012)

You would never know unless you check with a paint gauge. Different paints require more cut. Resprayed could lead to thicker paint or thinner paint. 

How long is a piece of string buddy?


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## Hasan1 (Jul 1, 2011)

Iv done my bmw 3 times and I still have 145 microns on most of the car so a good few times still but on 1 part where someone keyed it had to wet sand and only go 90 microns so I need to stay away from there no car is the same


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## Trip tdi (Sep 3, 2008)

Sorry to hi jack this thread, if a car has 84 microns, can the panel be machine polished at all to a safe level ?


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## MA3RC (Jun 19, 2012)

I'm thinking of a brand new car here, no re sprays & with medium strength paint. It's just interesting to hear people's views


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## MA3RC (Jun 19, 2012)

Trip tdi said:


> Sorry to hi jack this thread, if a car has 84 microns, can the panel be machine polished at all to a safe level ?


No worries


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## G4V JW (Jul 6, 2012)

You could go on about PTG for pages , but it really depends on the correction needed , you could have a million microns , but if your scratch/defect is a million and one deep it ain't coming out surely ? Thick paint that Lol

If you want to just use a machine polisher but worry about how many times , use it with glazes instead of polish , then you can go over and over , always looking like you're getting a good finish but never actually cutting at all !


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## chrisgreen (Mar 30, 2012)

G4V JW said:


> If you want to just use a machine polisher but worry about how many times , use it with glazes instead of polish , then you can go over and over , always looking like you're getting a good finish but never actually cutting at all !


I assume the same could be said for using a polish like SRP, which has little or no cutting capability?

I'm finally getting a DAS6 for Christmas and could also do with a bit of a steer on how frequently I can attack my Citroen C4 with it. I have no idea about paint thickness on it (don't have a PTG, no plans to get one either) but will mostly be using the DAS6 to take some of the effort out of applying SRP or Megs Ultimate Polish, rather than looking to undertake full-on cutting paint correction (I'd still rather pay a pro for that).


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## aimyv6 (Jul 17, 2011)

What about a fibreglass car? 3-4 times in its life as its not a new car


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## Bero (Mar 9, 2008)

Twice as much and 1/2 the clear coat depth -50microns, or 3.14159265359 times.

Impossible to say even for average thickness/hardness paint, a weekend warrior might wade in with 3M FCP on a wool pad and remove 15microns per time 'V' a professional that takes 200 paint depth readings and professionally lit studio and spends 30mins trying different combinations to get the best results for minimum CC removal might only remove 3 microns per time.


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## The Cueball (Feb 8, 2007)

Trip tdi said:


> Sorry to hi jack this thread, if a car has 84 microns, can the panel be machine polished at all to a safe level ?


Is 84 the total level?!?!

It doesn't really matter what the total figure is... it's how that is made up...

This is the big downfall in the cheaper readers....

for example:

You could have 84, of which 80 is clear coat...

You could have 352, of which 2 is clear coat...

Low levels don't mean danger, and high levels certainly don't mean safe...

At the end of the day, no matter what the reading, I would think most modern cars all have a base coat, paint coat and a clear coat... some fit all that in 84 microns, some take 130 microns! 

As for the OP question of how many times you can polish a car... how long is a piece of string???? :lol:

:thumb:


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## Porkypig (Jun 20, 2012)

Some very wise answers there and also take into account what sort of polishing you mean.

Are you correcting followed by regular finishing, or do you mean correcting once a year? I know its obvious but a light buff with the right pad a polish combo will take far less out of the paint than a heavy duty correction. :buffer:


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## Bero (Mar 9, 2008)

Trip tdi said:


> Sorry to hi jack this thread, if a car has 84 microns, can the panel be machine polished at all to a safe level ?


I would not polish it heavily - as a possible indicator of CC thickness pop the bonnet and take a reading from the engine bay/underside of the bonnet. These areas may not have CC. If they give readings of <30 i would proceed with caution, if they're >40 I'd only be glazing or maybe finishing polishing.

My 30 and 40 readings are nothing more than my thoughs, i'm sure some (many) will disagree......and they're probably right!


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## organisys (Jan 3, 2012)

S1600Marc said:


> No worries


Errrrr.... If this is a clear coated car, won't this rather depend of how thick the individual layers are? If the base or primer is thicker than normal, the depth of the laquer could be less than you think.

Really you need to find an unlaquered surface to compare with, or ideally a multi part PDG.

Edit: Skim reading... See Mr Cueball's excellent reply above.


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## organisys (Jan 3, 2012)

Bero said:


> I would not polish it heavily - as a possible indicator of CC thickness pop the bonnet and take a reading from the engine bay/underside of the bonnet. These areas may not have CC. If they give readings of <30 i would proceed with caution, if they're >40 I'd only be glazing or maybe finishing polishing.
> 
> My 30 and 40 readings are nothing more than my thoughs, i'm sure some (many) will disagree......and they're probably right!


Exactly.


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## mike_olney (Nov 8, 2012)

Trip tdi said:


> Sorry to hi jack this thread, if a car has 84 microns, can the panel be machine polished at all to a safe level ?


on average overall thickness of 84 you should have about 21 microns of top coat. this always best guess unless you fork out for a for top end gauge that can break down the layers.

following the rule of max 10% removal you only have 2 or 3 microns,

so start with menzerna p085rd on a blue 3m pad and do a test panel.

and take it from there you might be lucky and your paint will look ok.

mike:wave:


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## lowejackson (Feb 23, 2006)

chrisgreen said:


> I assume the same could be said for using a polish like SRP, which has little or no cutting capability?
> 
> I'm finally getting a DAS6 for Christmas and could also do with a bit of a steer on how frequently I can attack my Citroen C4 with it. I have no idea about paint thickness on it (don't have a PTG, no plans to get one either) but will mostly be using the DAS6 to take some of the effort out of applying SRP or Megs Ultimate Polish, rather than looking to undertake full-on cutting paint correction (I'd still rather pay a pro for that).


I would look at the previously suggested PO85RD or some Optimum Polish II, the cut from the Optimum (SMAT) is based upon the pad and pressure you are using plus it has a near endless polishing time. Also clean up is very easy, no need for IPA just wipe with a damp MF cloth


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