
Advanced Class - Pictures & Comments
Meguiar's Car Care 201
Saturday August 11, 2012
Another great day of wet sanding and rotary buffing, with a special surprise guest!
Just as we were getting ready to start the class, Barry Meguiar pulls up in his '32 Ford Roadster and asked if it would be OK to interrupt us and say "hi". Would it be OK???? Well of course it would!!! Barry may be the consummate car guy, but he's primarily a people person and loves talking cars and car care with other car guys.
After our usual classroom portion of the day we step outside and get down to some serious work. Since sanding and rotary compounding can remove significant amounts of paint, we want to take some paint thickness readings before we start.
Here we talked about the importance of using the foam interface pad when damp sanding. In this shot, without the interface and using a sanding disc over a body contour you can see how we not only lift the abrasive media off the paint in the low spot, but we also put undo pressure on the high spot. This can quickly lead to sanding through the paint on the high spot.
In this shot we have the foam interface pad in place and we're using a foam backing finishing disc. You can clearly see how the foam allows the media to conform to the contours of the body panel. Now, we still wouldn't recommend just blindly sanding over this area like this, but if you do it this way you have a huge safety margin over not using the interface pad.
OK, let's get starting sanding. We start with 1500 grit finishing media, using our Unigrit finishing discs.
Properly sanded, the surface is very uniform with zero gloss.
Here we've followed up the 1500 grit sanding with 3000 grit and you can start to see the reflection of the overhead lights. That's right, we were still sanding the surface, but we actually increased gloss by sanding. This yields a very uniform and predictable sanding mark that is much easier to remove with the rotary buffer and M105 Ultra Cut Compound. It's also much less invasive to the paint compared to trying to compound out a coarser grit sanding mark.
Of course we want to make sure we have a clean pad to start with, so we cleaned our wool pad in the pad washer.
First step with the buffer is to compound using a wool cutting pad and M105
Don't fight the rotary - you control it, it doesn't control you.
And do NOT run the pad up on edge like this!!! This only leads to buffer swirls (AKA holograms). We repeat - do NOT run your buffer in this attitude.
Wiping off the M105 residue reveals a return to a gloss finish.
But the first pass didn't make the paint perfect. We still have some sanding marks and a bit of buffer swirl, so we need another pass.
Cleaning the wool pad with a pad spur to make sure it remains clear during the compounding process. Do this regularly and the work will go faster and you'll get a better result.
If you're not familiar with using a rotary buffer but are skilled with a DA, you should be able to make the transition easily enough, but you need to keep in mind that everything is amplified when using the rotary. That includes heat, and that can be dangerous. Here we show the escalation of heat on the paint surface with a wool pad. 95F was reached fairly quickly, but that temperature is well within the safe zone.
It didn't take long to bump that up to 117F, however, so you really need to keep an eye on things and not get overly aggressive with this tool.
A foam cutting pad will generate a lot more heat, and much faster, than a wool pad will. Here we hit 133F in just a few seconds.
And a few seconds later we reach 204F on the paint surface! This is extremely dangerous and can do real damage before you know what's happened. You really want to avoid this at all costs.
OK, back to correcting the paint. Here we've moved to a foam finishing pad and M205 Ultra Finishing Polish. Again, you don't need to fight the rotary, just control it. Relax, don't tense up.
Following the demo it's time to turn the students loose and see how they get on with all these processes.
With the sanding done and the first round of compounding with M105 and a wool pad we see some light holograms, but the sanding marks are gone. This is good!
Following with M205 on a foam finishing pad we end up with crystal clear paint. This is awesome!
A clear reflection on his good work!
If you aren't having fun when doing this, you're just doing something wrong!
Finishing off black paint with M205 - beautiful!
Thanks to everyone for coming out on a sweltering Saturday and being so enthusiastic about learning these advanced paint care processes, and a special thanks to Greg for taking such great pictures during the demo!
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