Why is using scuffing pads wrong?
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I keep on reading that using scuffing pads is wrong but I use a grey norton scuffing pad with some adhesion promoting soap almost every day to prep panels. I find that it dulls the paint really quickly and evenly, especially in the parts that are hard to hit with sand paper. For that reason I wouldn’t feel right if I painted something that I didn’t use a scuffing pad with adhesion soap on.
I know a lot of people choose not to use this method out of fear of something but I don’t even really know what that something is. Could someone tell me if there’s credibility to these things not working?
There is nothing wrong with that. Many people prefer prepping panels with a DA (typically 500-800 with an interface pad) as it is very quick, and since it is dry, the panel can be masked and painted right away.
Scuff pads are fine, as long as you do it correctly and manage to abrade the panel enough. The only issue with using the paste is ensuring you clean the panel properly when done. Otherwise any leftover paste will dry a thin layer of residue, causing adhesion issues. Abrade it well, make sure you are even with it, and inspect when dry to ensure there aren’t any shiny spots. I believe grey pads with paste is supposed to be the approx equivalent to P800 dry.
If it works for you, and haven’t ever had adhesion issues, then no need to stop.
i have been using grey and red scotch brite pads for long time now, i use them with panel wipe in a pump can, i use grey on met colours and the red for solids. i like this method because it also gives panel a good de-greasing etc.
and i have never had any adhesion problems either, although you do have to make sure you get into all the tight areas.Yeah I found ever since I’ve been using these pads I’ve never had an issue with paint peeling off when I’m unmasking. Not even one time.
I have a theory about adhesion and that’s that it doesn’t really matter what grit you sand with because sand scratches in general are all you need.
And nope grey pads will not even get you close to 800 dry. When I do bright silver I have to bring body work to 1000 wet for it to match the pad prepped area.I also wouldn’t mind to know your system for cleaning once you’re done. I have to wash the car with wet shop towels then dry it off and begin masking.
I still use the scuff pad & paste method now and again. I prefer it when doing a larger job or one that’s had a lot of filler work, as I find it helps to remove the dust better than the more modern dry prep methods. Not all will agree, but we all have our own little quirks 🙂
I use a grey Mirka ultrafine pad, and usually break them in first on a dark coloured job before I’ll use them on something like a silver. A fresh one straight out of the box is too rough I reckon. I use them with NEXA scuffing paste.
I’ll do a panel at a time to ensure it doesn’t dry on. I’ll then wipe the panel over with a wet microfibre cloth a few time rinsing in between to remove the residue, then dry with paper towel while blowing out the edges with an airline. I’ll then check I’ve got every area properly, then move on to the next panel.
When all of the panels are done, I’ll wipe down with a strong slow solvent degreaser / silicon remover (DeBeer 1-951) then it’s ready to mask. A final quick wipe with the same degreaser after masking to remove any finger prints or tape residue, and it’s off the the booth.
[quote=”pierceg” post=26391]Yeah I found ever since I’ve been using these pads I’ve never had an issue with paint peeling off when I’m unmasking. Not even one time.
I have a theory about adhesion and that’s that it doesn’t really matter what grit you sand with because sand scratches in general are all you need.
And nope grey pads will not even get you close to 800 dry. When I do bright silver I have to bring body work to 1000 wet for it to match the pad prepped area.I also wouldn’t mind to know your system for cleaning once you’re done. I have to wash the car with wet shop towels then dry it off and begin masking.[/quote]
:blink: 1000 wet is about the same as 800 dry.
When using the paste, I keep it wet until it can be rinsed. Then I usually take some of the car wash soap and wipe, then rinse. I blow/wipe dry with disposable shop towels and inspect the parts. Then mask. In the booth I clean with wax and grease remover and/or isopropyl then finally glass cleaner (helps with the water base coat).
We are using the Carbo Fibratex pads
Huh, I’ve found that sanding wet shows less scratches than sanding dry, regardless I think if you sanded 800 dry on light silver you would definitely see it. Maybe Nexon pads are closer to 2000, I’m not sure.
And Andy, our systems are almost the same but I scuff everything before I clean it up. I then have a roll of blue shop paper towels, I rip one off dunk it in water then wash the car, as soon as it gets dirty I toss it to my feet and get a new one. Once I’m done I’ll rip off a dry one and dust off the remains of the, now dry, residue. Then there will still probably be a white streak here and there that the wax remover will get rid of once I’m done masking. I know it seems silly to change a system to save a few seconds here and there but when you don’t get paid by the hour and you have to finish painting half a car, body work, prep and paint before 6, cutting seconds out off a system makes this actually possible.
I’ve spoke about this on other threads that my creed isn’t to neglect the little things because the little things are what sets you apart from everyone else. But hey I don’t want you to think I’m some sort of hot shot, I understand that there’s a very good chance that you can do what I do just better and faster. I could of just misunderstood what you were describing. I really don’t want to sound like a dick by critiquing people I just notice I had a nice little path when I work on cars that gets me the bare minimum really quickly.I prep all my blends with 800 dry on a DA. Silvers, Golds etc. and yet to have a problem. Been doing it for years….
[quote=”pierceg” post=26397]Huh, I’ve found that sanding wet shows less scratches than sanding dry, regardless I think if you sanded 800 dry on light silver you would definitely see it. Maybe Nexon pads are closer to 2000, I’m not sure.
And Andy, our systems are almost the same but I scuff everything before I clean it up. I then have a roll of blue shop paper towels, I rip one off dunk it in water then wash the car, as soon as it gets dirty I toss it to my feet and get a new one. Once I’m done I’ll rip off a dry one and dust off the remains of the, now dry, residue. Then there will still probably be a white streak here and there that the wax remover will get rid of once I’m done masking. I know it seems silly to change a system to save a few seconds here and there but when you don’t get paid by the hour and you have to finish painting half a car, body work, prep and paint before 6, cutting seconds out off a system makes this actually possible.
I’ve spoke about this on other threads that my creed isn’t to neglect the little things because the little things are what sets you apart from everyone else. But hey I don’t want you to think I’m some sort of hot shot, I understand that there’s a very good chance that you can do what I do just better and faster. I could of just misunderstood what you were describing. I really don’t want to sound like a dick by critiquing people I just notice I had a nice little path when I work on cars that gets me the bare minimum really quickly.[/quote]What are you using for paint? With most brands I uesd (PPG, Dupont, Sikkens) in water and solvent base I haven’t had issues with sand scratches showing. I tend to finish my painted panels in P500-600 dry on a DA and blend areas with P800 on a da & grey scuff pads around the edges. No sand scratch issues, and for these prodcuts, finishing in 1000 wet would be unnecessarily tedious.
I wonder if the products you are using are just different from us. Some brands of paint hide scratches better than others, and many brands of sandpaper aren’t completely comparable by advertised grit. Like the Purple 3M clean sand 800 seems to leave a more aggressive scratch than the Carbo 800 or even the old purple 3M 800.
I was using the basic 3m sand paper and I found that the 800 scratches that I didn’t go over with the pad came out a little brighter. And I don’t really work up to 1000, I cut the primer a bit with 800, then 1000 for a while around the 800 then I go back to the pad, sometimes I won’t even cut the primer if it’s in low light.
Are you using p grade paper?for eg sia p1000 paper is actually 500 grit and p800 is 400 grit.I use carbo preimer red paper,the primer is usually finished in 400-500 and I will use 800 on an interface pad to prep blend panels or the norton/carbo foam backed hand sanding paper.It works for us and we don’t have a sand scratch problem.
i find that the Mirka products work very well, remember that the area must be sanded uniformly and consistently
i stopped using superfine/grey scotchbrite for blends a good long time ago ,i have never had much faith in them in regards to physical adhesion ,personaly i sand everything with 400 DA or where i cant get in with a DA i use a Fein multitop oscilating sander fitted with a 77mm pad with an interface it can even sand under door handles and on the smallest of edges without breaking through ie total control 😉 ,for blends i use a clear foundation coat to fill the scratch this way i am 100% certain of adhesion with no fear of any scratch showing ,also as bonus i find clears lay better over a foundation coat than over sanded or scotched clear
In my experiance its the next poor bugger who finds out if the scotched area has failed or after a stonechip or scratch starts the delam process ,personaly i dont like seeing my jobs fail even months or years down the line so i sand them properly if i didnt care i would go into the SMART repair game 😉
Paul
[quote=”ARTSPRAY” post=26580]i stopped using superfine/grey scotchbrite for blends a good long time ago ,i have never had much faith in them in regards to physical adhesion ,personaly i sand everything with 400 DA or where i cant get in with a DA i use a Fein multitop oscilating sander fitted with a 77mm pad[/quote]
Great idea with the Fein will have to give it a try :clappy
I been using 3M products for over 15 years,
Red pads for solid colors and grey for metallic.
I also use a few drops of dish washing soap per gallon of water to get grease off he car.
My first time spraying metallic color onto a panel I was blending silver that I sanded with a red pad did I learn I had to use the grey pads for a finer surface where the metallic flakes did not stand up in the coarse sanding marks from the red, it does not do this in the grey..
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