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TheCoatingStore.com

69-er
02-23-2013, 12:35 PM
I've seen several references to using a DA for color sanding, (and a comment or two using it on the last pass with 3000 Trizact). Since I have never cut and buffed a car before I am really hesitant to use this method. Would this be recommended for a rookie? I can't imagine using it nothing but flat surfaces. Is it possible that by the time you reach 3000 there is less of a danger to cutting through to the clear?

Henry
02-23-2013, 01:13 PM
I've seen several references to using a DA for color sanding, (and a comment or two using it on the last pass with 3000 Trizac). Since I have never cut and buffed a car before I am really hesitant to use this method. Would this be recommended for a rookie? I can't imagine using it nothing but flat surfaces. Is it possible that by the time you reach 3000 there is less of a danger to cutting through to the clear?

I've been wetsanding and buffing cars since I was 14 and that was on lacquer paint.

Then after 'many' years I found this site. A few years into this site, Len introduced 'finish film'. I orderded some along with the INTERFACE PAD and had this fear to put a DA and 1200 paper on my new bc/cc paintjob. I put the new stuff on a shelf for about 9 months.
Then, like you, I kept reading posts on this site, got the RIGHT DA and went for it. Gotta tell you this; I never looked back and probably have NOT wetsanded anything since. I was very cautious in the beginning and started with a decklid which was pretty much flat. I liked the ability to work dry and see what orange peel I removed and what amount I wanted to leave. As I sanded I became better with the sander and learned how to get into edges by backing the DA to the edge and good use of the trigger.

You should be using a 3/32 DA with a medium or a little less trigger. Just watch what you're doing (do 18 inches square to start) and keep the area clean on a FLAT surface. You can gain not only experience but CONFIDENCE. Pretty tough to burn through unless you don't have enough clear, have no regard for peaks and edges or you are an idiot. (no pun intended - just saying) You'll quickly get rid of the interface pad once you gain total control of your DA.

You should paint a hood or decklid (parts pieces) and try DA sanding that to see what happens. I probably will NEVER wetsand again AND I never tried the Trizac assortment of finer grits - that's cuz I do less work now and what I do shoot is acceptable with sanding/buffing. LOSE YOUR FEAR!

Henry

69-er
02-23-2013, 04:08 PM
I saw a dry method like this somewhere. On TV, I think. Didn't pay much attention to it. The sandpaper doesn't clog? Which DA trigger to you prefer? Palm or trigger? I have a palm trigger DA and the center of gravity seems like it would be lower compared to the trigger type. That would help keep it flat I think.

Mine's a 3/16" throw but Len sells this one. http://autobodystore.net/Merchant2/graphics/00000001/avnon.jpg

Do you use just the 1200 grit? No finer? What size disc?

Thanks, Henry!

Bob K
02-23-2013, 04:27 PM
Thatís my sander, a 3/32 AirVantage. Yes the Finish Film clogs when it is used up. When you get pills on the paper you can clean it off but the second use wonít last long and the third time is just a waste of time and effort. Better to put a clean sheet on. I switched from Finish Film to Trizact Clear Coat Sanding Discs. You use them wet. I have a squeegee with me and check progress by wiping the water off and looking for shiny spots. When the spots are gone, the clear if flat. I use 1500 grit only. I donít know if they make them in other grits. They cost something like 2 of 3 times as much as finish film but last 10 to 20 times longer so they are cheaper in the end. Hope that gives you something new to think about.

Bob K

James M
02-24-2013, 01:47 PM
I agree with Bob and Henry. Finish sanding a new clear coat is most definitely a job for DA like the Dynabrade or a Airvantage. (actually there are several other brands on the market now that would probably work just as well, lesser expensive but then they probably won't last as long as an Airvantage or a Dynabrade. I have a couple Dynabrades but the Airvantage is equal in job performance and quality. I use a 3/16 DA with finishing film wet ( I never dry sand with finishing film because it clogs up the paper too fast, won't clog up if you use water/wet sand). Wet sand with finishing film and sandpaper will last a LONG time. I never go to 3,000 grit either, 1500 us usually when I go to rubbing compound but once in a while I will finish if off with 2,000 grit before going to the compound on the buffer.

Long story short - If you put at least two good coats of clear on the car and the paint went on relatively smooth (no moon crater orange peel) and you start out with 1,000 girt or 1200 grit then you should have no problems cutting through the clear into the color coat. Keep in mind that the finer the sanding grit the less clear coat it actually removes while sanding. If you're sanding with 1500 or 2000 grit wet on the DA then you're really not removing much clear. Another thing to remember is keep the DA moving, if you sand long enough in one spot no moving the DA then you very well could cut through the clear into the color coat. Keep a black rubber 3M squeege right near you so you can stop sanding and squeege the water off a section often to see how it looks (need more sanding? sanding looks done ? etc) .

Also keep in mind that nothing will make the paint look flatter than hand wetsanding with a sanding block. A combination of using the DA first then finishing off by hand with a good sanding block can be a good combination (if you're looking for a show car type paint job, most paint jobs finished sanding with a DA/finishing film works fine).

dlmrun2002
03-02-2013, 03:32 PM
I'm surprised I don't see more talk on this type of work using Hutchins 7544 waterbug. I like it with the waterfeed, great for removing orange peel, scratches, painted pin stripe and much more.

dlm ny country

dlmrun2002
03-02-2013, 07:09 PM
If ya lay it down nice you will never go back to hand sanding. Easy answer.


Some of us non professional painters with other jobs who are car enthusiasts need some help along the way!!
dlm ny country

Henry
03-02-2013, 08:00 PM
Some of us non professional painters with other jobs who are car enthusiasts need some help along the way!!
dlm ny country

What do you need any help with? Just ask.

Henry

dlmrun2002
03-04-2013, 08:00 PM
I'm just saying pro autobody guys have more experience then us non pro's and can lay the paint down better. Non pro's like myself get more orange peel thus we need to sand down to level it out. That's all.
dlm

Len
03-04-2013, 08:13 PM
I'm just saying pro autobody guys have more experience then us non pro's and can lay the paint down better. Non pro's like myself get more orange peel thus we need to sand down to level it out. That's all.
dlm

I'm not a big Hutchins fan but I've never used the Waterbug so it may be a good tool. The AirVantage is light and has a real low center of gravity which makes it great for wet sanding prior to buffing. If the peel is real bad you can start with some 1200 or even more coarse if you have enough paint on the surface. I normally start with 1500 Trizact wet then go over it with 3000 Trizact wet prior to buffing. If you hit it with 3000 it's normally very easy to buff. If you've ever sanded orange peel by hand then you try a good orbital sander you'll never go back to doing it by hand unless it's just for tight spots where the sander can't go.


http://autobodystore.net/Merchant2/graphics/00000001/avnon.jpg
Link (http://autobodystore.net/Merchant2/merchant.mvc?Screen=PROD&Store_Code=ABS&Product_Code=AVS61100S&Category_Code=T)

Henry
03-05-2013, 11:02 AM
I'm just saying pro autobody guys have more experience then us non pro's and can lay the paint down better. Non pro's like myself get more orange peel thus we need to sand down to level it out. That's all.
dlm

I sent you a PM. Let me know if you get it.

Henry

greg hardman
03-07-2013, 04:57 PM
If ya lay it down nice you will never go back to hand sanding. Easy answer.

You've been looking at too many badly painted cars. I can't believe the heavy orange peel I see on the nicer cars.

greg hardman
03-07-2013, 05:05 PM
I've seen several references to using a DA for color sanding, (and a comment or two using it on the last pass with 3000 Trizact). Since I have never cut and buffed a car before I am really hesitant to use this method. Would this be recommended for a rookie? I can't imagine using it nothing but flat surfaces. Is it possible that by the time you reach 3000 there is less of a danger to cutting through to the clear?
I DA with 1500 on tubular structures and have no problem. You just have to know your DA and gauge the thickness of your coat.
Slowing down will help as well as wet sanding with water or denatured alcohol

Len
03-09-2013, 07:52 AM
I DA with 1500 on tubular structures and have no problem. You just have to know your DA and gauge the thickness of your coat.
Slowing down will help as well as wet sanding with water or denatured alcohol

Welcome Greg
Are you sanding wet or dry? I looked at your web site (http://www.renovobikes.com/), quite impressive.