We want to preface this article by pointing out that the processes discussed here are fairly advanced and should not be entered into lightly by a novice. But if you have any experience at all with wet sanding (or in this case, damp sanding), then this process is something you really should consider in appropriate circumstances.
When dealing with truly severe defects in paint the most common approach to defect removal has been very aggressive rotary compounding, but this process can pose some problems.
What if there was an easier way? What if there was a process that.....
- was less destructive to the paint
- had a short learning curve
- was less messy
- guaranteed no buffer swirls
- didn't require a lot of cleanup when done
What if there was a process that provided all that but still removed severe defects quickly?
3000 grit to the rescue!
Using Meguiar's 3000 grit Unigrit Finishing Discs has several advantages to aggressive rotary compounding when removing severe defects:
This process can be used for spot repair of severe defects, panel repair after painting when grossly improper use of a rotary has left massive holograms, or even on an entire vehicle if the whole car has been severely neglected over time.
- the precise, uniform grit particles give a smooth and even sanding pattern for fast buff out
- "finishing" disc means a specialized foam backing that, when used with a foam interface pad, will not remove texture from the paint so you maintain a uniform texture match throughout the vehicle even if you're only doing extensive defect removal on one panel
- quickly refines sanding marks and removes severe surface defects
- utilizes a damp sanding process - minimal water usage and no specialized sanding lube
Let's look at how conventional rotary correction compares, step by step, to utilizing the power of 3000 grit.
We start with a panel that exhibits severe, random defects.
Step 1: Major Defect Removal
Historically a detailer would reach for a very aggressive process to correct this mess. That often means a wool pad on a rotary, along with a very strong compound. This process can be very invasive to the paint, can generate a lot of heat, and very often creates a series of holograms that then must be buffed out with another step. This is also a fairly time consuming and potentially messy operation.
By substituting the above process for DA application of 3000 grit sanding media, you actually remove the existing severe defects in less time, but you do so without introducing any heat to the paint whatsoever. And since you are DA applying the 3000 grit you are being less invasive and more controlled with your defect removal. Further, the resulting sanding marks are very uniform and predictable, unlike rotary induced holograms. That means removal of the sanding marks is a very straight forward operation.
Below you can see the resulting finishes produced by the two options: rotary compounding on the left, 3000 grit damp sanding on the right. What may really surprise you is the time taken to achieve these two results: a full 1 minute, 55 seconds was required of the rotary and wool pad, while the 3000 grit result you see here was achieved in just 35 seconds!
Step 2: Refining the Finish
Of course, now we need to remove the marks we created in step one. Using traditional rotary techniques this means moving to a foam finishing pad and a finishing polish. Depending on how severe and random your holograms are, this step can be fairly straightforward, or it can be rather frustrating. There is still the potential for the introduction of heat into the paint, and even some light hologramming. It takes a very high level of skill to finish out completely hologram free with a rotary buffer.
Using the DA Microfiber Correction System, we are able to easily remove the 3000 grit sanding marks. And since this step uses a DA buffer, the learning curve is much shorter than that of a rotary so virtually anyone can do it, and since a DA can't create holograms like a rotary can, there's no need to worry about that.
The net result of our comparative second steps yields very clear and glossy paint. The DAMF System process actually takes a bit more time in this step, 1 minute 20 seconds versus just 40 seconds for our demonstration panel, but it leaves a completely defect free finish whereas the rotary side may not.
Step 3: Waxing
Using traditional methods a DA buffer is generally used to apply a liquid wax. Using the DAMF System we're staying with the DA but we're making use of a wax designed for incredibly fast application and single wipe wipe off. This along gives an edge to this step of the process. This step, using traditional methods, took just 38 seconds to fully work in the wax.
A light touch and surprisingly fast movements over the paint is all that's needed to lay down a coat of D301 Finishing Wax. Here we needed just 17 seconds to cover our test area.
So, what do we get overall when comparing these two methods? Well, we have the same number of steps, and the end result looks virtually identical from one process to the other. But even just on this one section we saved more than a full minute when utilizing the power of 3000 grit and the DAMF System. Our recorded cumulative time for the traditional methods was 3:16 and the 3000 grit/DAMF method was 2:12. Add that up over the entire vehicle and the time savings, while maybe not hugely significant, is noticeable. But that time saving is only part of the picture.
If you're going to be doing the "traditional" process on an entire car you're going to have to tape off all the trim before you get started, and you're going to sling product and make a bit of a mess. This means extra time spent up front, and even more time spent cleaning up after the fact, or maybe even rewashing the vehicle following the compounding stage. With the 3000 grit/DAMF System taping off trim is optional, and since there is no product sling there is nothing to clean up after the fact.
But what's really important here is how much safer and less invasive to the paint the 3000 grit/DAMF System can actually be. Heat is usually the enemy of a modern paint system, and you just can't avoid generating heat when rotary compounding. But damp sanding with 3000 grit introduces zero heat to the paint, and when used with a DA the process is highly controlled with minimal material removal.
This process is great for spot repair, too. Using a foam interface pad with the 3000 grit finishing disc will actually allow you to follow existing paint texture while removing below surface defects. This means you won't level out the existing orange peel in your spot repair area, so you do not end up with an area that looks visually different from the surrounding area. And you won't be grinding away at the paint with a traditional rotary process in order to remove extreme defects from a confined area.
OK, so the above was basically a test demo; how does this all work in the real world? Well, below are a couple of examples of the type of spot repair that can easily be achieved with 3000 grit media:
This BMW not only had some pretty bad swirls throughout the paint, but these really nasty scratches on the hood as well. The swirls were removed with traditional buffing methods, but had we just gone after these bad scratches with traditional methods we would have been grinding away on this paint for a long time, with the very real risk of over heating the paint. Instead, we DA sanded with just 3000 grit to take out the worst of the scratches, then removed the sanding marks. Ultimately we obtained the finish shown in the second image. We therefore removed these isolated, severe defects in less time with less stress to the paint.
This poor Honda was scraped by another car, leaving what at first looked like just some paint transfer and a few light scuffs. But it turned out to be much worse than that (including a crease in the sheet metal under that painfully obvious white line).
We could easily remove the really light defects with traditional buffing methods, but ultimately had to reach for a 3000 grit finishing disc and damp sand the area, which is what we're doing in the image below.
After 3000 grit damp sanding to remove the worst of the defects.
The DAMF System was then put to use to remove the 3000 grit sanding marks.
The crease in the sheetmetal was bad enough that it prevented the DA sanding process from really getting into it, so we touched up by hand and then gave it one last run with the DAMF System.
All cleaned up and looking almost like new once again. We say "almost" because at the right angle and with the right light you can still see the crease in the sheetmetal. But since you can't buff out a crease in the metal, and we don't do paintless dent removal here, it's not a 100% fix of the damage. But again, by opting to utilize the power of 3000 grit and the DAMF System, we removed all of the paint defects very quickly, and with very little heat stress to the paint.
As we mentioned at the start of this article, damp sanding is a bit of an advanced process, but then again so is rotary buffing. In many ways, however, you can more quickly become proficient at DA damp sanding than you can at rotary buffing. If you stick with 3000 grit and use some common sense you can accomplish some remarkable defect correction without subjecting the paint to undo harshness, and you can accomplish the task in less time than using traditional buffing methods. Obviously this is not a substitute for routine DA buffing to remove light to moderate swirls, and you should always adhere to the concept of "use the least aggressive method to get the job done". If that means a DA with foam pads and a quality paint cleaner will get the job done, then you shouldn't just damp sand "just because". In that case you will add extra steps, which adds to your time, and you will remove more paint. But in cases where you just can't remove defects using traditional buffing methods, or you know you'll have to buff very aggressively for an extended period of time, the power of 3000 grit can make the process go much faster, and with less overall risk.
Add this process to your detailing arsenal, but choose wisely when to make use of it. Practice on a discarded body panel and before you know it you will have mastered the process, added to your skill set, and improved your overall abilities as a detailer.
*We would like to thank Jason Rose for inspiring this article and providing some of the basic, core information provided here.