What did I miss?

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Mr.B

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Ok, my sister in law came over with her new (used)car. I took one look at it and I knew it needed help. Scratches all over the place. Some of the scratches I knew that I could not do anything with because my figure nail would catch on them. But the scratches on the images above, I was sure that I could make them disappear because they didn't seem or feel deep.

I washed the car, clay barred the entire car, took my DA Porter Cable and went to work. No matter what product I used; Maguire's DA compound correction and Da pad. cutting pad with Turtle rubbing compound and then Maguire's rubbing compound. Nothing even made these things look any better. I had the DA speed maxed out, I went over a 2x2 area several times, slow with over lapping stides.

What should I have used? Was I asking to much out of the DA to smooth these scratches out?


Thank you for your help.
Brent
 
How old is your PC? Mine started getting very, very weak after 11-12 years. It took only a slight bit of pressure to keep the pad from spinning. Did you happen to notice if it was spinning? If not, try a piece of tape on the backing plate to make sure it rotates freely, and use as much pressure as you can, while still allowing it to rotate.
 
May I ask if you did a test spot that delivered the end result you were after?
From your post it doesn't appear so.. thats I guess point #1... saves a lot of work for a disappointing result..

Lets go through the things that make a differance on the basis that to date your product selection has insifficient cut...

Machine; its a DA, to get cut the back plate MUST be spinning, not stalled, do you have it marked to be able to see this?
Machine technique; are you applying a small load to the machine on horizontal panels which DOES not stall the polisher.. some load is required.. this load is increased on sides as no gravity to assist...
Machine technique; you mention a 2' by 2' section which is good, (although if DAT products break down too easily YOU HAVE TO SHRINK THE WORK AREA..., you may want to accurately achieve a 6 pass pattern.. see mikes video's for clarification... they are very good

Pad selection; on a DA it is not uncommon at all on harder paints to require a microfibre cutting pad, meguiars are good at cut and finish down reasonably, expect to need a pass with foam finishing pad / light polishing pad after this on harder paint.. Even heavy cut foam pads can struggle on very hard clear.... For a fafster rate again you will need to step into either FLEX or rotary territory, which is also fine.. but has its own knacks...

Compound selection; a good diminishing compound often works well and finishes nicely, however on very hard paint some (many ) diminishing compounds break down before much cut is achieved (especially if you don't shrink the work area) , so it takes forever to correct.. solution, select a SMAT (non diminshing compound) which will increase your work time and cut rate, or halve your work area and don't be in a rush....

Keep in mind with more cut comes greater chance of damaging paint (especially on edges).. be aware...

Finally with increased cut comes incresed pad loading (compound and old clearcoat gumming in the pad) and hence more need to clean / swap out pads for fresh... doing so maintains the cut rate and makes progressing across the car easier to plan.. ie you have consistent work rate and result.. a clogging pad will drop off its effectiveness so you slip into a downward spiral..... it also incareses the risk of contamination in the pad causing pig taisl etc.

Please be aware it is likely you will want to polish the paint after you have compounded to raise the gloss.... again its still harder paint so anticiate using a slightly stronger diminishing polish and medium polishing foam pad.. slow work rate allowing the polish to break down and hence gloss... keep everyhting clean at this stage and agina change pads after perhaps each panel or 2.. small dirt here can ruin all the hard work you have just done....

I always seem to end up fixing cars with hard paint... with the right products (rotary and wool pads with SMAT).. its no harder than medium paint and actually easier IME than really soft paints.. (they are their own breed of PITA)..

I hope something in that lot guides you toward the result you are after..

All the best..

Short cut.. get megs DA MF cutting pads.. use ultimate compound in reduced work areas, follwo the tips on Mike vid, keep it clea..
Repeat with orange foam pads and megs ultimate polish....
 
Also sometimes the scratches are under the clear from a bad paint/body repair and will never polish out.
 
Spray the scratches with water ,do they disappear? If yes they are definitely surface clear coat scratches and are fixable
 
When you say "da compound, and da pad" what products are you exactly referring to?

Which Turtle Wax and Meguiars product after that did you try? What are the exact names on the bottles? What pads did you use with these?

What size pad/plate?

What model Porter Cable 7424, or 7424xp?

How much pressure are you using?
 
The PC is about 6-7 years old. I have a white line on the backing plate and it was turning freely. I tried different amount of pressure each time I went over that area.
 
Your right, I did not do a test spot. I am just a man that thought I could fix the world in one day. lol
Thank you for your info, that did help me think of other things the next time I give it a try. Is there away to tell if the what type of paint your up against?
 
I would start here:
Dual Action Orbital Polisher Guide: how to remove swirls, scratches, & oxidation with an orbital buffer. Porter Cable 7424, foam pads, backing plate,

What Meg pads were you using? I often find the MF pads aren't the best choice... Just recently on two different cars I had better luck with my BOSS White Foam Cutting pads (the most aggressive foam pad in the GG line-up). They removed defects and finished off nicely.

Change your pads often. For compounding you should 6 for a vehicle.
http://www.autogeekonline.net/forum...-how-many-pads-do-i-need-buff-out-my-car.html

You've got a lot of good advice here already.
 
Maguire's DA microfiber, with DA correction compound,
Turtle Wax premier Renew RX rubbing compound with the Cobra light cutting pad (orange)
Maguire's ultimate compound with the Cobra light cutting pad (orange)
PC is 7424xp

I tried all different pressures, very light, to just enough pressure making sure my white line was moving.
 
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