How to know when enough is enough?

[caudleej]

I know this subject probably gets beat to death but I am always wondering when it is time to make the call to not compound and or polish paint anymore in order the maintain the longevity of the clear coat. I have been wondering this even more since I have dealt with scratches on the hood of my personal vehicle. I have polished the entire vehicle with m205 and a lo profile foam polishing pad shortly after I bought it to remove the DISO. I have kept it sealed and waxed and have only used compound on a few local areas for a deep scratch or scuff and I have polished the entire vehicle with a very fine polish/wax a couple of times. I started using waterless products to wash the vehicle and used them for several months. Although I was very careful and used plenty of clean premium towels I damaged the paint. I was sort of figuring this would be the case with frequenting the use of waterless washes. I made up my mind to correct the paint and use a high grade sealant and not touch it anymore with waterless products. I had to break out my microfiber cutting discs with the m205 to get most of the scratches out because they were deeper than traditional swirls. I did this and then followed up with another fine polish on a foam polishing pad just to increase the depth.

Since all this I have noticed scratches on my hood that I guarantee are from debris and contaminants blasting the hood while driving because they are all in straight lines in the direction the wind travels across the hood. I know I could easily break out the da and some m205 and get them out but I feel like I have already touched the paint enough.

The the vehicle is going on 5 years old and is a white tri-coat paint.

Looking forward to everyone's input.

[Just02896]

Only way to know for sure would be to purchase an affordable electronic depth gauge or borrow one from someone who owns one.

[TTQ B4U]

What make and model? Paints very quite a bit.

Can't say for sure for many reasons, but I'll tell you that our van is 10 yrs going on 11 years old and has been hit with compoud in areas to remove some bad stuff. It's been polished twice per year and going strong. Unless you've leaned into the car with some really tough products you should be fine.

Polish it up and put a coating on it. You'll be fine.

[Hantra]

And after you measure the depth, you'll have a number that still doesn't answer your question. You won't have any idea how much of that number is clearcoat, and how much you can polish before you blow through that, and need a repaint.

[lawrenceSA]

Only YOU will know the answer to the question...by measuring the paint thickness to see what you have. Sure unless you drop thousands of dollars on a PTG that can read individual layers, you will only have an IDEA of the paint thickness, but even a cheap PTG gives you enough usable info to make an educated decision.... for example you can identify repainted panels, spot areas that are very thin compared to the rest of the paint and can get a fairly good idea of the amount of clear by measuring inside a door shut to get a base reading.... just remember these numbers are just a guide to help you.... not an absolute yes/no kinda thing.

To my mind, anything 120µ and up is enough to do a decent compound on, 100µ to 120µ is starting to get close to 'thin' and I'd probably only ever want to compound it once, 80µ to 100µ is thin in my books and if possible, really shouldn't be compounded, and anything below 80µ is definitely not 'compound' material in my eyes.... however, having said all of that, more and more cars are coming out with thinner and thinner clear coat from the factory, some even as low as 80µ on brand new paint....and each manufacturer will presumably have their own rules around how much clear can be removed without voiding any sort of warranty etc, so make sure you take all of that into account too before deciding how to proceed.

You also need to factor in what the car means to you - is it your beloved garage queen with original paint that you intend owning for the next 20 years or a cheap daily driver you plan on replacing in a few months.... the importance of clear coat preservation will vary depending on the value of the paint, to you, if that makes sense.

Then, assuming you have identified there is enough paint to polish, conduct your test spots to dial in a system that removes enough paint to get rid of the damage, to a level that is acceptable TO YOU - the more aggressive this initial cut, the more likely you will need to follow up with a subsequent polish to refine out the initial cutting haze and restore gloss and clarity to the paint.

Then do everything you can to minimize future swirling and you shouldn't then need to do any additional heavy compounding.