HELP PC 7424 did almost nothing?????

[michele3873]

I detailed our new (used) black BMW 530xi this weekend for the first time. The car was in pretty good shape with mostly slight swirl marks/scratches (probably mostly done from washing/detailing incorrectly by the cars previous owner). There were a few deeper scratches that you could feel with a fingernail that I didn`t expect to get out. There were also a few hard water spots (acid rain?) on the door and one white paint mark (probably made from a white car door hitting my door) which was only a faint surface mark.



I did a ton of research and purchased a PC 7424 with 6" Lake Country pads (white, orange and yellow). Also purchased the Zaino Z-PC (since I was doing the Zaino method), but also purchased the Menzerna Intensive Polish (IP) since I had read that it was slightly more aggressive in getting imperfections out.



I started with the orange pad and Zaino Z-PC. It didn`t seem to be doing much, so I went up to a the Mezerna IP with an orange pad. Still didn`t seem to be making much difference so I went up to the Mezerna IP with a yellow pad....and still not much difference. :sadpace:



Overall I saw some of the light swirl marks go away, but I can still see many light scratches (like they were from a towel) that stayed. The watermarks and the light paint marks on the door also stayed. I just don`t get it. I have seen some amazing results posted online from detailers using a PC. I spent hours (my arm practically falling off) going over the car and it really seemed like the PC did nothing for my cars paint. I didn`t even get the "haze" that everyone refers to with the Menzerna IP and yellow pad...which makes me think even more that it wasn`t "cutting" like it should.



What could I have been doing wrong? I worked the product on setting 4 for a bit and then moved up to setting 5 and worked it for several minutes in each area. Wiped it off and saw no hazing whatsoever. Do I need a more intensive product than IP? BMW paint can`t be that hard.:nixweiss

[Thomas Dekany]

Can you post pictures of it? Did you go over with comething after the yellow and IUP combo?



How old is the car? BMW paint in general is very hard. May need a rotary.



Also where are you located?

[rjom]

I always use setting 6. I spread with setting 3.

[imported_sal329]

I think the problem rests in the 6" pads. Try some 4" pads

[Legacy]

I think the problem rests in the 6" pads. Try some 4" pads

I agree and if that doesnt work get some PFW pads.

[nooboob]

I don`t know much about detailing, but if you do some research, alot of people here have had better results with 4`` pads. Reason being the power is spread out at a larger distance with a 6``, that less power is applied respectively.



Can you post some pics? I`m interested in seeing your work.

[JasonS]

Smaller pads help, increase the speed setting to 6 and make sure to move the polisher slowly using overlapping patterns. Left to right, then front to back. Concentrate on a small area at a time. I suggest a 2x2 foot area. Polish this area till it is perfect and then move on the the next section. Once you perfect one section, move on to the next.

[jfelbab]

Welcome to the forum. Since I don`t know your experience, please don`t be offended if if this post seems too basic.



Is this your first time using the PC? How large an area and how much pressure were you applying? How long did you work the polish? How much polish did you apply? Did you clean the pad frequently? Did you thoroughly shake the polish before using?



Some paint is harder than others and requires more work time.

•Spread the polish at speed 3 and then move up to 5 or 6 to polish.

•Do a small 1.5` x 1.5` area at a time.

•Press down on the PC until the rotating motion begins to slow but not stop.

•Apply very small amounts of polish and clean the pad against a cotton towel after each pass or two.

•Move the PC very slowly back and forth and side to side for at least a couple minutes or until you see the polish clear but don`t polish it dry.



Here is a YouTube video of the polishing steps.

YouTube - Car polishing featuring Porter Cable 7424

[michele3873]

Thanks for all the tips. Like I had mentioned before. I had done a ton of research online (autopia forums especially) before we started detailing the car.



I agree, I had read that 4" pads have more cutting power...but since the 7424 kit I purchased came with a 6" backplate, I figured I would try the 6" pads first. I guess I will order the 4" pads for the next go around...but considering I just spent $50 in pads with not much success...I am less than thrilled with the idea of spending another $50 in new pads.



We worked a 2` x 2` area at a time. Put about one swirl of product on the pad (which I had seen done in one demonstration video). Spread the product at speed 4, and then moved up to speed 5 to work the product in using a horizontal and then vertical motion on the car (again, all as I had seen done in an online demonstration video). Was using about medium pressure on the 7424 and worked the area until the product was almost gone (a clear creamy residue)...which was probably about 5 minutes. I then wiped the area clean.



I didn`t clean the pads "frequently" as there didn`t seem to be any build up on the LC pads. Do you think that could have been the issue?



I also didn`t follow up with a white polishing pad after using the Yellow with IP because I never saw any hazing . My main purpose was to get the minor scratches out...which it wasn`t very successful at.



I didn`t take any "before" pictures. I will take some "after" pictures and post them later.

[lexusgs]

You definitely want to go with 4" pads if you want to get rid of swirls, light scratches, water marks, etc with a PC, the 6in just don`t seem to cut it for most correcting with a PC. You don`t need to spend $50 in pads either. With 4" pads all you need is 3 or 4 oranges, a 3 1/2 backing plate, and maybe 2 yellow pads and that is not going to cost anywhere near $50, you could probably get them for under $30 including shipping if you look hard enough. Also when correcting be sure to apply a good amount of pressure on the PC and go over the area several times in several directions, if it dries too fast add a little water or lubrication. Some of the more stubborn defects I had to press pretty hard and go over a few times to get them out but a PC with Menz IP and 4" orange or yellow pads will certainly get rid of most swirls, light scratches, water spots, etc it is just going to take some hard work. A BMW clear may be harder, not sure if they use a ceramic clear coat but if IP does not seem to work as well you might want to step up to something a little more aggressive or something made for ceramic clearcoats which Menzerna makes.

[Thomas Dekany]

I can never understand why one would not use speed 6 to correct.:laugh::laugh::laugh:

[imported_DetailDan]

Speed 6 is the only way to go when using the PC.

[Legacy]

Speed 6 is the only way to go when using the PC.

Speed 6 with 4" pads is the best way to correct with a pc.

[rjom]

I have five black cars, from a 1993 mercedes to 2000; my kids never took good care of them, but I was able to get all of the swirls out of all of them with the PC. The very fine scratches are another matter, but you can hardly see them unless you look real close. But I set it on speed 6. I have the 6 inch pads. The PC works pretty well on all of these vehicles. Why aren`t you using speed 6?

[Scottwax]

Speed 6 is the only way to go when using the PC.

:werd: Even then, correcting with a PC on today`s harder paints is going to take time. Just no getting around it.



What I would do is work on the car over the next few weeks, maybe spend an hour or two on each section so you don`t spend 20 hours at one time on it. Just work on a section at a time and get it as perfect as possible.