Thickness gauge(s) guestion

[wifpd4]

I've been struggling this week with some scratches and have had this problem before on other cars. I'm not sure when to give up and live with a scratch. They start out deep, but not so deep as to be able to feel it with your finger nail. So my belief is I should be able to get it/them out out. However after using some aggressive products, pads and techniques the scratch is reduced but still visible. Often, but not always, the scratch is in a location I need to use a 4" pad on the PC. I step up to an orange LC pad and buff away.

I worry about getting too carried away and reducing the clear coat too much, so I stop and live with the scratch and you all know once you've cleaned the finish of hundreds of swirls that lone scratch sticks out like a sore thumb. I think I get pretty aggressive. As Mr. Stoops has indicated, getting too aggressive with a small pad on a plastic bumper can cause problems. I crank away and the hook and latch interface between backing plate and pad heats up and the bumper starts to get warm, verging on hot. So I back off and quit.

Today I can't afford, nor know which, thickness gauge to buy. This is what I believe to be the basic concept, take some measurements around and or in similar locations as the scratch to get a fair idea of how much paint is available. Start buffing and retest trying to leave some paint before damage appears.

As I understand it, you need two thickness gauges. One for metal and one for plastic.

So are you sitting at your computer thinking, yep a thickness gauge will help you out, but until you have a full understanding of what you are doing you've got no business touching a thickness gauge and since you're not really in the detail business you don't need a thickness gauge? Or are you thinking, give it a whirl?

Or do you have some buffing advice for these isolated, pain-in-the-neck scratches.

Thanks,

[rapport25]

Re: Thickness gauge(s) guestion

Hi Wifpd4,

I detail cars as a hobby/part time job. Due to work increasing via recommendations. I decided to invest in a paint depth gauge last year and I find it great!!!! I was not aware you could get one for plastics.

15 yrs on I still consider detailing full time but dont seem to get much work from Oct-Mar. Thats Uk weather for you!!!.

I always give the customer a copy of paint depths over the entire car. I have found that this gauge has saved me on around 3 cars. One being a Bmw that was showing only around 60 microns on the boot lid heavy scratches and swirls were present. On Bmw's I have detailed they tend to be 120-180 depending on model year of manufacture.

Basically I explained to the customer I would polish and not using any form of cutting compound due to very very thin paint.

Back on topic.Is it your own car? And what colour? If the scratch is to deep you wont get it out. It would need a re spray.

I would try a touch up pen with a tooth pic and try and fill then wet sand it back. Or air brush the area.

Hth's Rappy

[ClearlyCoated]

Re: Thickness gauge(s) guestion

I lucked out and bought a Centech 95520 for a great price a few months ago from another member on Megs. I had been looking for one ever since I read this review on AutoGeek.

Unfortunately, as noted in that thread, Harbor Freight no longer carries the Centech 95520, but you can find them on eBay for just over $100.

[wifpd4]

Re: Thickness gauge(s) guestion

...
Back on topic.Is it your own car? And what colour? If the scratch is to deep you wont get it out. It would need a re spray.
...

The two cars I've worked on recently, not my own, each had a single scratch that didn't look too deep. Both cars were black and coincidentally the scratches were on the top side of the bumpers. So could really get some downward pressure on the buffer, using a Lake Country 4" pad with M105 in one case and Ultimate Compound in the other and a PC DA. I grind away until the pad gets hot, as does the bumper, moving the PC at least four inches each direction away and back over the scratch. I was hoping the thickness gauge would stop me from removing too much clear coat.

I lucked out and bought a Centech 95520 for a great price a few months ago from another member on Megs. I had been looking for one ever since I read this review on AutoGeek.

Unfortunately, as noted in that thread, Harbor Freight no longer carries the Centech 95520, but you can find them on eBay for just over $100.

Thanks for the links, this is useful information. Do you use the Centech on each car you do. Do you use it to determine your "safety factor"?


Thanks gentlemen for your interest. I'm fairly certain my clients would not notice these scratches. I just hate busting my butt on a paint correction job and have this scratch glaring me in the face, when I think I should be able to remove it (them).

[Andrew C.]

Re: Thickness gauge(s) guestion

I have a highline meter II and I have one of those scratches you are talking about. It really is only noticeable to me because I know it is there.

I've always taken a shot at it every few months or so, just because it bothered me. Once I got my PTG, I measure it compared to the surrounding area and it was about 3 or 4 mils thinner. I figured that I reduced the appearance, but I'm not gonna work on it anymore, I just don't want to make what is now a little problem into a big problem by wearing through my clear.

[wifpd4]

Re: Thickness gauge(s) guestion

...I just don't want to make what is now a little problem into a big problem by wearing through my clear.

EXACTLY!! Well stated.

The problem is once you remove millions of scars, leaving one sticks out so badly.