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gav'spurplez
06-06-2006, 04:46 PM
ok,



so i have some "decent" sized rock chips on my from bumper,



if i use touch up paint with a tooth pick and allow it to dry,

then wetsand with 3000 grit then polish and wax, should look ok, right ??





any info or tips would be great.

the other pc
06-06-2006, 10:40 PM
The trick is to buff any scratch out of the surrounding factory paint, which is waaaay harder than the touch-up.



By using Meg’s Unigrit #3000 paper, confining your work to a very small area including the chip and not working much into the surrounding paint (cut teenie, tiny sized pieces of paper to use) you should be able to buff it out without much trouble.





PC.

gav'spurplez
06-07-2006, 02:43 PM
well what about these guys on here, wetsanding orange peel on whole panels and

such.



i think my front bumper needs to be wetsanded anyways.

never looks as nice as the rest of the car when fully detailed :xyxthumbs

the other pc
06-07-2006, 04:04 PM
When you mentioned "wetsand with 3000 grit then polish and wax" I assumed you meant polishing by hand or PC. Guys wetsanding orange peel over large areas normally follow sanding with one or more steps of heavy compounding with a rotary before polishing to final gloss.



A rotary can deal with sanding scratch in the surrounding clear more readily. If you`re going rotary anyway minimizing excess scratch may be less of an issue but any time you compound you reduce the thickness of the available factory paint that much more. You only get so much to play with.



If the patch is relatively large, the factory paint hard and the touch-up very soft there`s some risk of buffing through the touch-up before you`ve removed the scratch from the surrounding factory paint.



If you sand the whole the bumper do the work carefully and methodically. Paint on bumpers tends to be thinner and less durable than paint on open panels. Plastic bumpers insulate heat so the surface temperature rises quickly when rotary buffing. The paint will burn more readily than on metal panels.





PC.

gav'spurplez
06-07-2006, 04:13 PM
so, the PC is not "strong" enough to follow wetsanding huh ??



eh, that sucks,



need to do something with my bumper before it gets too bad. :aww:



any suggestions

Accumulator
06-07-2006, 05:14 PM
If you wetsand with Meg`s 3000 grit Unigrit paper you oughta be able to polish it up with the PC, especially if you use 4" pads; I`ve even done it by hand. Rotaries really are best for this however.



But I don`t get the "need to do something with my bumper before it gets too bad". It`s more likely to "get bad" if you wetsand it and take off a little too much clear than it is if you just leave it alone. Well-maintained paint generally doesn`t get worse than it already is.



It`s not unusual for the paint on plastic components to be a bit different from that on the regular body of the car (color, texture, thickness, hardness- different in all sorts of ways). And since the paint on plastic panels is often more fragile anyhow, I myself wouldn`t do anything that might compromise it`s longevity.



I`d approach wetsanding this way: you gotta accept that your efforts might end up necessitating a repaint, so ask yourself whether a) you feel lucky, b) a repaint would be better or worse than the current situation, and c) if the cost of a repaint is gonna be an issue. IMO it`s better to have thick original paint than to have thinner paint or a repaint, but that`s just me.

gav'spurplez
06-07-2006, 06:26 PM
well,



the paint itself is not the problem, it is the rock chips i would like to eliminate.

Accumulator
06-08-2006, 09:47 AM
OK, now I understand!



If you have a zillion of them you might just want to get the bumpercover reshot. I had Accumulatorette`s front bumpercover redone last year. Touching up just a few is one thing, but a lot of them, well, I`d rather just spend some money on it and have it resprayed. It`s not that big/expensive of a job.

gav'spurplez
06-08-2006, 11:29 AM
not alot, not even close, but i thought touching it up might look semi-messy,

therefore, touch up - wetsand - buff resulting in a better look ;)

Accumulator
06-08-2006, 04:01 PM
Yeah, OK, I`m with you now. I`ll be in the same boat with my `97 M3 when (if?) my mechanic ever gets it back to me. The previous owner didn`t sand his touchups and they look pretty bad, so I`m planning to fix the worst of his and do my own touchups right. Sure does complicate an otherwise simple job tough...

MrSelfDestruct
06-09-2006, 06:20 PM
I use 1500 grit, cause it`s fast (ppl can argue that it`s too agressive, but i`m careful with it)



put on touchup paint, 1 light coat and let it dry for 15min or so, then another coat that is higher than the regular paint on the car. Let that dry good cause it will sink in a bit.



If it`s a flat surface I use a sanding block to keep it flat, if it`s curved I use my hand and be very careful.



Without putting much force at all, spray water while going at it gentley and start paying attention once the colored water (excess touchup paint) starts running off. Once it feels smooth use a chamois and wipe the area dry. If it looks uniform then go for the rubbing compound, polish, and wax (I use a rotary, dunno how a PC would do the job.. never used one).

gav'spurplez
06-10-2006, 10:49 PM
thanks for the info !!!



maybe 2000 would be better, since i have heard ideas about 1500 and 3000



i`m going to test the process out on my 2002 sentra, the camaro will not be the "test mule" :nono



i`ll have to post a pic of the tiny rust spot on the hood, maybe you can suggest a fix for it,

gotta love the daily drivers too you know :buffing: