"Cover Passes" explanation please..

[Perfectshine]

Hi all,

Today i tried 'cover passes' after the first stage of cleaning the paint with #83 with the polishing pad on a rotary..

The problem is that, i am not so sure that i did it right after reading or even searching for more info on this forum.. so it was just for the sake of trying it out and see what the outcome was..

Im working on a friends mk6 Golf GTI clear coat.. there's light swirls and hologram/buffer trails on the finish.

Working under the halogen spotlight.. im able to finish about 90% perfect..

So what i did for this cover pass step was, buff each panel dry without applying any product.. with uniform surface in mind..

Checked the surface under the halogen light, just minor random scratches but and an improvement in overall gloss under normal lighting condition..

Is this correct or am i wasting my time instilling light random scratches?

edit: and im planning to go with #80/polishing pad/rotary to follow up and #80/finishing pad/DA, NXT 2.0/finishing pad/DA.

Please advise. thanks.

[Perfectshine]

Re: "Cover Passes" explanation please..

*bump*

[Murr1525]

Re: "Cover Passes" explanation please..

I'm confused... so you used #83? Then used the dry polishing pad? And then are going to remove the marks from the dry pad with #80?

That would sound a bit of a waste, #80 should clean up anything left behind.

[Mary S]

Re: "Cover Passes" explanation please..

I have never heard the term "cover pass" but I don't think you are ever supposed to use a pad dry, unless you are deliberately trying to mar the surface. Did someone say you should use a pad dry?

[Michael Stoops]

Re: "Cover Passes" explanation please..

So what i did for this cover pass step was, buff each panel dry without applying any product.. with uniform surface in mind..

Is this really what it sounds like - you buffed the paint with a dry foam pad on a rotary buffer, with no liquid product at all? That is not anything we would ever recommend. Can we ask where you heard about this process?

[Perfectshine]

Re: "Cover Passes" explanation please..

Murr, I went all over one panel with the same polishing pad that i used with #83, but not applying product on it this time in one pass, hopefully to tie all the work together.

I tried searching for it and found that it's been mentioned in the 'how to articles' - learning how to use the rotary buffer.

so how do we do this cover passes?

[Perfectshine]

Re: "Cover Passes" explanation please..

LOL, I know I need to hear more about this technique before going further.

I knew buffing dry is bad. I think i misunderstood what I've read and actually put it to action hoping not to miss anything.

Educate me more please.

[Mary S]

Re: "Cover Passes" explanation please..

Okay, if you are using 83 and 80 with a rotary and a polishing pad, you would use the 83 with the polishing pad, starting out putting down more pressure, then lightening up the pressure for a few more passes. Then you would use a new polishing pad with #80 and a lower speed, maybe 1200, and again, start with heavier pressure for the first couple of passes then lighten up the pressure. The heavier then light pressure has to do with the fact that these are diminishing abrasive technology, you lighten as the abrasives diminish. The SMAT technology like 105 and 205 are different, you don't need to do this.

You can see a 5-part demo video on Youtube, and I think he uses those 2 polishes.

http://www.youtube.com/watch?v=6f8EQNVxxbw

This is the first one, it will take you to the others.

[Michael Stoops]

Re: "Cover Passes" explanation please..

OK, when buffing with any tool, you always want to add at least some fresh product for each area you're going to buff. Generally speaking you want to keep the work area confined to roughly 2' x 2' in size - this can grow a bit when doing some final polishing, depending on the products used, how the paint responds, etc. But for your defect removal/paint correction/paint cleaning you want to stay within that small area. Rotary or D/A, makes no difference.

So within that area you'll lay down a bead of product and pick it up with the rotary, (or make a circle or "x" on the pad of a D/A) then work it methodically against the paint in that area. Moving side to side or up and down, overlap your passes by about 50% and take your time. Fast movements with a rotary will inflict holograms, while fast movements with a D/A just won't accomplish much since you need that dwell time for the product/pad combo do actually work. Buff the area until the liquid product is just a thin film on the surface, but not quite dry. That's your indication that it's time to wipe off.

Now repeat the exact same process on an adjacent 2' x 2' section, but overlap your passes so that you overlap into the previous work area. Again, buff until the liquid product has become just a very thin film on the surface and wipe dry.

When working with a rotary buffer it is critically important to clean the pad regularly. After ever couple of 2' x 2' areas that you've polished, clean the surface of a foam pad with a nylon brush, and clean a wool pad with a spur or compressed air. This prevents the build up of product, which keeps your work area cleaner and keeps fresh product on the paint when buffing. When working with a D/A you want to press a terry cloth towel firmly against the pad and then switch the tool on. This will force excess product out of the pad and into the towel (it can't go out the back side of the pad because of the backing plate). This is much more critical with M83 than it is with M80 as M83 is more prone to dusting. But keep that pad clean and you'll greatly minimize the dust from M83 and find your experience with it as enjoyable as M80.

It should be noted that these two products utilize a diminishing abrasive, so you do need to use a roughly equal amount of product for each 2' x 2' area that you're buffing. With the new SMAT (super micro abrasive technology or non-diminishing abrasive) liquids you can use less product as you go since the pad will carry a bit of product with it from section to section. And since the abrasives in these liquids (M105, M205, Ultimate Compound, SwirlX) don't really break down, that product carried over will still cut very well. Within limits, of course. It's not like simply spreading wax where a wet pad will transfer product and that's all you need. But still, after the pad is pretty wet with a SMAT product you can probably buff your next section with just a few drops of fresh product rather than a full bead or "X" on the pad. You still want to clean regularly, however, to prevent build up of drying product on the pad.

As for this process...

edit: and im planning to go with #80/polishing pad/rotary to follow up and #80/finishing pad/DA, NXT 2.0/finishing pad/DA.

Sounds good to us, but if you're going to follow with M80 on the D/A anyway, you can probably skip the rotary step with M80 and just do this:

• Rotary/M83/Polishing Pad (maybe even a cutting pad for hard paint/severe defects)
• DA/M80/Polishing Pad
• NXT 2.0/DA/Finishing Pad

[Perfectshine]

Re: "Cover Passes" explanation please..

Mary S, Awesome reply! Thanks for the effort, but I understood on the applying & lightening pressure with DAT's. The cover passes is what I'm curious about. Anything to just bring up my work higher and better.

[Murr1525]

Re: "Cover Passes" explanation please..

As Mike said, might have gotten overlapping passes confused in there? I suppose some people might do a big 'overlap' at the end if they want, but yeah, the pad will still be wet, not dry or drying out.

[Mary S]

Re: "Cover Passes" explanation please..

Mary S, Awesome reply! Thanks for the effort, but I understood on the applying & lightening pressure with DAT's. The cover passes is what I'm curious about. Anything to just bring up my work higher and better.

YW, just quoting from what I remember from that video! But I guess I never heard the term cover pass, unless it has to do with overlapping your passes, but it doesn't sound like that's it. I heard Mike Phillips talk about section passes. When you find out, let us know!

[Perfectshine]

Re: "Cover Passes" explanation please..

Michael, all my knowledge on polishing came from this forum, salute to you & meguiarsonline! Thank you! Will post up pics when I'm done soon after we get this cover passes cleared up.

Murr, I thought so too.. Mike Phillips mentioned that it might leave some haze or swirls making me think that I only go through the whole panel with the used pad..

Mary s, we'll definitely share this.

[Mary S]

Re: "Cover Passes" explanation please..

I found this while googling:

"Excellent points. When I'm using M66, I will work in initial passes as though I'm using M80. That is, I will apply 15 to 20 pounds of pressure and work it very slowly and deliberately. I wipe it off between applications, again treating it like a polish. Then on the final cover pass, I'll lighten up the pressure a bit and just let it fully dry, till it passes the swipe test."

So he is talking about a cleaner wax here, where he is treating it as a polish, heavier then lighter pressure, then lets it dry like a wax, and wipe it off as usual for a wax, but this would be after he is done polishing with the rotary. Does this make sense? He kind of left that part out. But he must mean "cover pass" as the pass to get rid of any earlier hazing, buffer-induced swirls.

[Perfectshine]

Re: "Cover Passes" explanation please..

Mary S, try googling- site:meguiarsonline.com "cover passes"

Then click on, learning how to use the rotary buffer. Scroll down till you see the "cover passes" in bold. Was randomly browsing through the forum insearch of stuff to learn. Came across that thread and wondered, how come I never did cover passes?