Is a Rotary The Only Way??

[07maximan]

In the next week or so Im going to be painting the roof of my car black. Ive been doing A LOT of research as this is my first attempt at painting. I bought a scrape fender to play around with and I feel pretty confident I could it. Color sanding is obviously very important to the final out come,but what about polishing??

I currently have a Porter Cable DA buffer that Ive been using for other projects,will this work for the final buff or do I have to use a rotary? Ive never used one before and Ive heard some horror stories so Im a little nervous.

Also,is there a write up on what process I should follow to achieve great results with polishing? I want to really only use Meguiars because Ive always had great success using their products. Any tips or advice would be very helpful!!

[Murr1525]

Re: Is a Rotary The Only Way??

Hmm.. I will be intrigued about an answer for this.

With being able to work your way up the new 3000 grit disks, and MF system... maybe it is possible.

[07maximan]

Re: Is a Rotary The Only Way??

Hmm.. I will be intrigued about an answer for this.

With being able to work your way up the new 3000 grit disks, and MF system... maybe it is possible.

Whats the MF System?

[Murr1525]

Re: Is a Rotary The Only Way??

http://www.meguiarsonline.com/forums/showthread.php?47856-Introducing-our-new-DA-Microfiber-Correction-System&highlight=microfiber+system

http://www.meguiarsonline.com/forums/showthread.php?54950-The-Power-of-3000-Grit&highlight=3000+grit+disk

[stanclub]

Re: Is a Rotary The Only Way??

In painting, if you are able to control the clear coat flowing flat & well, then you will not need to color sand much, except any nib or dip sort of small imperfection. As fresh paint, you can sand with P2500 for correction, then DA compound to remove sand marks. However, to level the clear coat well is the real trick! Without right equipment, skill, and product ( type of clear coat used ), most people will get much of orange peels after repaint, then it calls for heavy color sanding. In that case, you might have to start with at least P1200 ( I started with 800 ), and work your way up. That will be the condition that you might not be able to remove all the sand marks by DA along, but rotary with wool pad.

If you have a panel to play with, try painting the panel with the clear coat that you have, then wait 16-24 hours before sanding. After the clear is fully cured ( not yet fully dry thu ), you can sand and buff, then try you DA to see if it can finish the job nice for you. Keep in mind that longer that you let the clear dry, the harder it gets. So, the fresh clear is usually easier to sand and buff soon after 24 hours of drying, but gets harder to polish after few days.

[07maximan]

Re: Is a Rotary The Only Way??

Thanks for the info. I just got done watching the 5 videos for the rotary...I might be getting in too deep.

[stanclub]

Re: Is a Rotary The Only Way??

Thanks for the info. I just got done watching the 5 videos for the rotary...I might be getting in too deep.

If you really want to stick with DA only, then try to shoot your clear in cooler temperature ( around 70 degrees ), and use slow reducer only. While shooting the clear, try not to tile your angle of nozzle ( gun tip ) while moving, but pointing straight toward panel in about 6in distance. Make sure the gun pressure setting is correct ( fluid, fan, and pressure ). All these will will reducing dry spot so you will spend less time sanding. Then, after proper amount of dry time for your clear ( check with your tech sheet ), start your initial sanding by P2000 with soft pad, then follow up to P2500, and finally P3000.

The clear coat will be much easier to sand after it just got freshly cured; the tech sheet will specify the buffing dry time. If you let it dry for few days or longer, as it drys harder, it gets harder to sand with P2000.

Since you are going to sand much out of your clear, spray at least 3 coats ( or 4 ) if you are using mid-solid clear. For high solid, 2 coats are usually ok, but 3 will be safer. However, you don't want to put too thick of clear because it might not look right after painting.

Good luck, and have fun

[Michael Stoops]

Re: Is a Rotary The Only Way??

If you finish sand down to 3000 grit you should be able to remove those sanding marks with your DA and our Microfiber Correction System. We did this very thing on a reprayed '66 Mustang at our last Thursday Night Open Garage and it worked great. We've also done plenty of DA Microfiber System work on other cars with 3000 grit finish sanding marks, and it's always turned out great. Rotary use in the hands of a novice can quickly turn bad, so we'd stick with the DAMF System to start.

[07maximan]

Re: Is a Rotary The Only Way??

If you finish sand down to 3000 grit you should be able to remove those sanding marks with your DA and our Microfiber Correction System. We did this very thing on a reprayed '66 Mustang at our last Thursday Night Open Garage and it worked great. We've also done plenty of DA Microfiber System work on other cars with 3000 grit finish sanding marks, and it's always turned out great. Rotary use in the hands of a novice can quickly turn bad, so we'd stick with the DAMF System to start.

So when you say "sand down to 3000 grit" do you mean only using 3000 or should I do a combo of maybe 1500 to 2000 to 3000??

[stanclub]

Re: Is a Rotary The Only Way??

So when you say "sand down to 3000 grit" do you mean only using 3000 or should I do a combo of maybe 1500 to 2000 to 3000??

It means, by the end, you should "only have" the sanding marks of 3000grit left over for compounding. If you started with 1500, you will need to follow up with 2000, then 3000. In each step up, you will need to sand the clear enough to "completely" remove the rougher sanding marks left by previous step. The difficulty in this case is that you can't really see the result while sanding, so you will need to scrub off the water often to check the result. Do a small test spot before you go on the whole panel, then you will get better idea how much to sand.

3000 grit is too fine for leveling, so you might not use only 3000 grit. Unless you can spray your clear really well leveled, and just want to even the surface and cut some shine; otherwise, you will start with less grit, and work your way up. Sand paper is a serious trick in sanding. Don't go by cheap paper, but good paper like Meguiars' or 3M finish film. A good sanding paper will make your life easier.

Ultimately, which combo to use is really determined by the clear coat surface condition and the hardness of it. For example, I sprayed 2 bumpers last night, and I was able to lay the clear down really flat and leveled, but got some dust nibs on it. In my case, I can sand the nibs off with 2500 grit, then 3000 grit to remove 2500 grit. At the end, I can DA compound it with MF system. If I got a lot of dry spots and orange peels on it, then I will have to start with at least P1500 ( I usually go 800 ), and patiently work my way up to 3000, then compound with MF system.

[ARCStig]

Re: Is a Rotary The Only Way??

Reading this makes me glad I'm going to Maaco to get my car painted... lol

[Michael Stoops]

Re: Is a Rotary The Only Way??

As stanclub points out, the grit you start with is determined by what you're really trying to accomplish: leveling orange peel or just refining a surface, or maybe removing dirt nibs. What you finish down to will ultimately determine how much buffing you need to do, and how aggressively you need to do it, to bring the gloss back to the paint. It's usually less invasive to the paint to finish sand with 3000 grit than to just grind away with a buffer in an attempt to remove 1500 grit sanding marks. And it takes less time, too!

[stanclub]

Re: Is a Rotary The Only Way??

Reading this makes me glad I'm going to Maaco to get my car painted... lol

It is funny that you mentioned Maaco; We are repainting my friend's 01 Ford Ranger, and we have just talked about Maaco yesterday, since they have been advertising $299 to fully paint your car. What I have found is some of Maaco stores will try to do good job, but many don't. And someone told me that he walked in for the $299 deal, but by the time he got his car back, he paid almost $3000, due to the right quality he wants, which I think is still not too bad when comparing to some of the professional shops ( my friend got a quote from one "pro" shop asking almost $8000 for his 01 Tundra, which he sold it for $7800 after we painted it ourself for about $900 in cost ). Hopefully, that Maaco you are going to is one of the good one.

There has alot of difference in process how to prep the car before repainting, and it requires time and profession. A well prep + premium quality material = excellent result & long lasting. Good job never cost cheap, but everyone demands different level of quality. So, that is why Maaco still in business, but I just never go there

[stanclub]

Re: Is a Rotary The Only Way??

[07maximan]

Re: Is a Rotary The Only Way??

Thanks for all the help guys,but I decided to leave this to the pros. I took it to a local paint and body shop and they're just going to do it for me. For 325.00 its not even worth my time!!