Removing 1000 grit wetsand with PC

[mikespine]

My brother-in-law has a Black 1996 Chevy Tahoe in which he wetsanded the entire vehicle using 1000 grit (maybe even more abrasive because I think he also pulled out 600 or 800 grit).

So after a wash, clay, wash.. I took the PC 7424 (my products are limited), some 3M Fine Compound, followed by #151 using an Orange Lake Country CCS 5.5" Cutting Pad.

WOW, that #151 really finishes nice. Although the above combo did get out some of the marks, not nearly all of them (suprised).

Naturally I want to work smarter not harder. Meaning I would prefer to use the PC vs stepping up and wetsanding the entire vehicle with 2000 grit.

I was thinking of going out to purchase the #105 and trying the PC (I know Meguiars recommends hand or rotary).

Any other suggestions? What is the Meguiars most aggressive cut product that can be used with the PC?-Mike

[Markus Kleis]

Re: Removing 1000 grit wetsand with PC

Hey Mike,

Any chance you can get some decent pictures of what it looks like? I would be curious to see if you are working on the sanding or pre-existing scratches.

Also, was the paint factory on the vehicle? Wet sanding with sandpaper that aggressive on a factory clearcoat (or is it single stage?) is VERY risky as you generally don't have a whole lot to play with OEM.

D151 is not intended to remove sandpaper that aggressive- heck, I don't even think there are compounds meant for sub 1,000 grit!

Again, pictures would be very helpful...but unfortunately my gut tell me that hitting it either either 2,000, or 3,000 grit sandpaper before breaking out the compound will be the best and easiest way to do this.

Do you have Meguiar's Unigrit sandpaper? I love the stuff (used it today, actually) and it is a lot safer (fewer tracers) than many papers out there. Meguiar's also sells a very nice backing pad to wrap the paper over for more even sanding.

Not sure if the Meguiar's direct store has it (Feel free to check!) but I know that www.AutoDetailingSolutions.com does as I got mine there.

For me personally, I find M105 (even by hand) can often remove the 3,000 grit sanding in a single pass, and it leaves an absurdly glossy finish (For a compound)! You can always try M105 by PC, and then do a final pass by hand for a slightly better finish (if needed). Or, you could follow the M105 with a milder polish like D151 and see how that works. When you try getting to your finer finishes (Like the D151 at that point) I would suggest going to a milder pad than orange- like a Meguiar's yellow for instance.

Keep us posted!

Mark

[Mike Phillips]

Re: Removing 1000 grit wetsand with PC

Naturally I want to work smarter not harder. Meaning I would prefer to use the PC vs stepping up and wetsanding the entire vehicle with 2000 grit.

Working smarter instead of harder would be to finish sand with a much higher grit paper with a minimum of #2000 and depending upon whose papers you use you could go up to #2500, #3000 and even #4000

The higher the grit you finish off with, the easier and faster it will be to buff-out the car.

Meguiar's does not have a recommendation for sanding down cars with the intention of buffing out the paint and removing the sanding marks using a DA style polisher.

To work smarter, not harder you would re-sand and finish with a higher grit paper and then use a rotary buffer with a wool pad and an aggressive compound to remove the sanding marks, not just make the paint shiny with sanding marks left behind in the paint which my guess is what you have now.

Questions?

1) How much time has passed since the paint job? Days? Weeks? Months? Years?

2) How much clear was spayed?

Sanding and buffing out an entire vehicle is a TON of work with a rotary buffer, trying to do an entire vehicle with a Porter Cable or even our G110 is unimaginable. Put it this way, you couldn't pay me to try to do it.

The most aggressive product Meguiar's recommends with the DA Polisher at this time is M83 Dual Action Cleaner/Polish.

A lot of people have good luck using M105 with a DA Polisher but there's no satisfaction guarantee when using it this way as it's not a recommended way to use M105

Time to invest in a rotary buffer and learn how to use it.


What forum led you to believe you could buffing #1000 grit sanding scratches using a DA Polisher? (Wasn't this one.)

[Mike Phillips]

Re: Removing 1000 grit wetsand with PC

I took the PC 7424 (my products are limited), some 3M Fine Compound, followed by #151 using an Orange Lake Country CCS 5.5" Cutting Pad.

Besides everything above... the Porter Cable will quit rotating the pad once your pad starts to get wet with product and you apply pressure to it or hold the pad on an angle.

You can read more about this in a reply I typed up last night here,

5th post down...

PC7424 + SONUS Pads + D151 = No Go

[mikespine]

Re: Removing 1000 grit wetsand with PC

Working smarter instead of harder would be to finish sand with a much higher grit paper with a minimum of #2000 and depending upon whose papers you use you could go up to #2500, #3000 and even #4000 (This was a similar thought, just looking for other alternatives)

The higher the grit you finish off with, the easier and faster it will be to buff-out the car.

Meguiar's does not have a recommendation for sanding down cars with the intention of buffing out the paint and removing the sanding marks using a DA style polisher.

To work smarter, not harder you would re-sand and finish with a higher grit paper and then use a rotary buffer with a wool pad and an aggressive compound to remove the sanding marks, not just make the paint shiny with sanding marks left behind in the paint which my guess is what you have now. (They are diminished, but still there-your are correct)

Questions?

1) How much time has passed since the paint job? Days? Weeks? Months? Years? (about 12 years, original paint 1996 Chevy Tahoe, washed 3 times in about 5 years per the owner of the vehicle)

2) How much clear was spayed? (no idea, original paint)

Sanding and buffing out an entire vehicle is a TON of work with a rotary buffer, trying to do an entire vehicle with a Porter Cable or even our G110 is unimaginable. Put it this way, you couldn't pay me to try to do it. (not being paid, my brother-in-law does not mind how it is now..decrease scratches and glossy)

The most aggressive product Meguiar's recommends with the DA Polisher at this time is M83 Dual Action Cleaner/Polish.

A lot of people have good luck using M105 with a DA Polisher but there's no satisfaction guarantee when using it this way as it's not a recommended way to use M105

Time to invest in a rotary buffer and learn how to use it.


What forum led you to believe you could buffing #1000 grit sanding scratches using a DA Polisher? (Wasn't this one.) You are right..it was not this one or any other. Just trying to get better results with what I have or a minimal purchase. Minimal to me at this time is not a rotary and wool pad.)

(I sort of feel like you are saying to yourself...("What is this guy thinking!)

[mikespine]

Re: Removing 1000 grit wetsand with PC

Working smarter instead of harder would be to finish sand with a much higher grit paper with a minimum of #2000 and depending upon whose papers you use you could go up to #2500, #3000 and even #4000

The higher the grit you finish off with, the easier and faster it will be to buff-out the car.

Meguiar's does not have a recommendation for sanding down cars with the intention of buffing out the paint and removing the sanding marks using a DA style polisher.

To work smarter, not harder you would re-sand and finish with a higher grit paper and then use a rotary buffer with a wool pad and an aggressive compound to remove the sanding marks, not just make the paint shiny with sanding marks left behind in the paint which my guess is what you have now.

Questions?

1) How much time has passed since the paint job? Days? Weeks? Months? Years?

2) How much clear was spayed?

Sanding and buffing out an entire vehicle is a TON of work with a rotary buffer, trying to do an entire vehicle with a Porter Cable or even our G110 is unimaginable. Put it this way, you couldn't pay me to try to do it.

The most aggressive product Meguiar's recommends with the DA Polisher at this time is M83 Dual Action Cleaner/Polish.

A lot of people have good luck using M105 with a DA Polisher but there's no satisfaction guarantee when using it this way as it's not a recommended way to use M105

Time to invest in a rotary buffer and learn how to use it.


What forum led you to believe you could buffing #1000 grit sanding scratches using a DA Polisher? (Wasn't this one.)

Besides everything above... the Porter Cable will quit rotating the pad once your pad starts to get wet with product and you apply pressure to it or hold the pad on an angle.

You can read more about this in a reply I typed up last night here,

5th post down...

PC7424 + SONUS Pads + D151 = No Go

Thanks for the info and link-Mike

[Markus Kleis]

Re: Removing 1000 grit wetsand with PC

Haha, no Mike Phillips realizes as much as ANYONE on this planet that learning has to start somewhere! Don't feel bad one bit. In fact, feel lucky because Mike Phillips put some serious time into those replies...a luxury he doesn't always have.

That said, in *my* personal opinion you are treading on some seriously thin ice, or clear coat in a literal sense with this project. Sandpaper like that on a paint job that old, neglected, and thin is crazy. But since the project is already under way your best bet would be to get some 2,000, and at least 3,000 Meguiar's Unigrit and carefully go over what has already been done.

From there, you are likely going to have to try M105 or #95 on the PC and follow that by a hand M105, and then PC D151 or #80. It's going to be a LOT of work...and I mean a LOT, but you don't really have a choice at this point.

Good luck!

[mikespine]

Re: Removing 1000 grit wetsand with PC

Thanks to both Mark and Mike for your quick replies and wealth of information. What is the difference between unigrit and a 3M sandpaper?-Mike (hope it is ok to ask this question in this thread)

[PorscheGuy997]

Re: Removing 1000 grit wetsand with PC

The Unigrit papers have very even abrasives. When wetsanding, this is very important because all the scratches are the same level.

Also, the Unigrit papers have a special backing that allows them to last longer in the water.

I've used the 3M a few times and now only use Unigrit papers. The difference in quality is huge.

[benhui86]

Re: Removing 1000 grit wetsand with PC

my question would be why...... unless he just repainted the car himself.... there should be no need to wetsand an entire vehicle and with such aggressive grit....

so anyways..... if you dont know how to use a rotary.... use 105 by hand.... it is going to take you quite a while bc its such a big vehicle but 105 would be your best bet to get rid of sanding marks..... you are not recommended to use 105 with pc bc it is likely to cause hazing.....so your safest option would be 105 by hand and then finish up with 151 on pc