PDA

View Full Version : Pre touch up prep?



Gopher
05-01-2008, 03:06 PM
I`m about to go after some rock chips on my hood with an autosharp pen and am wondering the appropriate prep work.



Specifically, I have a couple layers of 845 down which is still beading well... will this be a problem adding touch up paint over it?



I was thinking I should probably use some rubbing alcohol or something to cut straight to the paint on those areas followed by a water cleaning. Is this necessary?



Depending on how the application goes and how close the paint matches, I may try over filling the chips and wet sanding.



Any suggestions are appreciated.

SuperBee364
05-01-2008, 03:16 PM
Dangit, this again is where I can`t find an Accumulator post that talks about this very thing... *Somewhere* there is a thread by Accumulator that goes through this process from start to finish, but once again my searching abilities suck.



I believe he talks about making sure the surface is completely free of anything at all. Use prepsol first. He uses some company`s chip repair kit.... I`m gonna try looking for that thread one more time...



There`s another thread around here that shows pictures of the process from start to finish... might have been Picus?



Edit: Cool, I found Picus`s thread on this. Well worth reading. http://www.autopia.org/forum/click-brag/70028-small-how-chip-repair-wetsanding-spring-cleaning-black-g35-56k-owie.html

jedovaty
05-01-2008, 03:43 PM
Hey, Superbee, THANKS!!



For input from you or others...



Curious about that method of chip fixing - I received a little touch-up-kit from my dealer that includes both a tube of my paint color and what I think is clear coat. Once you get the color on, do you cover it with the clear? ????

Accumulator
05-02-2008, 10:20 AM
Funny that people always refer to my posts about touchups..heh heh, the ones I do on my vehicles always look terrible!



Yeah, use a good solvent to clean the area in question. PrepSol, Pre-Kleano, 3M Adhesive Remover. Don`t just use window cleaner or IPA.



Use rust converter if the chip is down to the metal.



Use tiny artist`s brushes to apply the paint (google "MicroMark" for a great place to buy `em). Yeah, they do work *that* much better ;)



Fill the chip most of the way up with basecoat. Do several light/thin coats and let them dry for a few hours each. Then add clear until it`s a little higher than the surrounding paint. I sometimes wait overnight before applying the clear.



Then level with Langka (sorry, you`ll have to google that too) or do the wetsanding. With the Langka, watch that you don`t wipe off all the touchup paint! Note that I often just leave the blobs there after using Langka to fix `em a *little* bit.



Yeah, that might be one reason why my touchups look crappy but mainly it`s because the (metallic) paint never matches. Somehow my good painter can do `em so well I have to *REALLY* look to find `em, but neither I, nor the other painter I use, can even come close to that level of quality :nixweiss



The big potential issue with wetsanding is that the sanding scratches that get in the surrounding factory paint can be a PIA to polish out. I guess the ones I wetsand look a little better than the ones I don`t, but eh...see what works for *you*. I usually just don`t want to do the whole compounding/etc. stuff that follows wetsanding as I`m usually touching up an Audi and that hard clear is a pain.



Oh, and watch that you don`t have an "oops" when wetsanding. You wouldn`t be the first.



Honestly, I wouldn`t clean off perfectly good Collinite to do this. I`d wait until the wax is on its last legs anyhow. For that matter, I`ve let chips go for ages (~20 years on the Jag`s hood) with no problems at all.

Gopher
05-02-2008, 02:38 PM
This is a BMW (titanium silver) so I`m sure compounding after will be a pain.



As far as why? My paint chips on my hood are bad. Driving in the mid west this winter when I took my fiance to chicago for x-mas really did a number on my hood. Looks like acne and is driving me nuts. It has to be done.



I`m planning a full detail anyway, it hasn`t been polished in 6 months and I`m itching to try some new products out, so this won`t be much extra work so long as I do the touch up first.



Thanks for the input all I`m gonna re-read the advice provided a few times before tackling it... (when my damn autosharp pen arrives... was hoping to do it this weekend!).

Accumulator
05-03-2008, 10:50 AM
This is a BMW (titanium silver) so I`m sure compounding after will be a pain...



If it`s an older BMW like my e36, then yeah, it might be tough. Maybe the Langka would be worth considering.



Good luck with this job, I find silver to be incredibly tough to touch up properly. Seems like the best I can do is get it to match from *one* viewing angle, and that`s seldom the angle from which you usually view the car :o (Example: Heh heh, if you stand on your head and look at it from a 45 degree angle it looks fine :D )



If you have a zillion chips maybe you oughta consider just getting the hood repainted.

SuperBee364
05-03-2008, 11:36 AM
If it`s an older BMW like my e36, then yeah, it might be tough. Maybe the Langka would be worth considering.



Good luck with this job, I find silver to be incredibly tough to touch up properly. Seems like the best I can do is get it to match from *one* viewing angle, and that`s seldom the angle from which you usually view the car :o (Example: Heh heh, if you stand on your head and look at it from a 45 degree angle it looks fine :D )



If you have a zillion chips maybe you oughta consider just getting the hood repainted.



Langka, that`s it. Don`t know why I can`t remember that name. Need to get one of those kits.

Gopher
05-03-2008, 03:58 PM
I went with an autosharp pen, as my usual supplier was back ordered on Langkas and I`ve read mixed reviews about them...



It didn`t arrive for this weekend as I was hoping, so I think I`m going to just get my jollies detailing our other car (fiancee`s Red Nissan Altima) which is in poor condition with no sealant/wax left at all.



I`ll post before/during/after pics of my bimmer when i get to it/receive my pen (hopefully during the week as I`ve got an e39 meet next Saturday!). Its not that old, an `03, but I`ve found the paint to be difficult to work with, though under normal lighting silver always looks great.

KrisMas
05-10-2008, 09:21 AM
Just a question guys. If you use presol do you use it full strength or water it down? And the other thing is can I use it in a spray bottle to spray, leave it on for a few seconds and wipe off?

Mindflux
05-10-2008, 09:25 AM
I used one of the Langka kits when they first popped up and never ever had much luck with it. They do have good customer service, though. I told them the blob eliminator was not eliminating the blob so they sent me the wet sand kit.



FWIW there`s a Mother`s touchup kit you could buy (or used to be able to buy) that was simply re-labeled Langka. If they still make it you should be able to get it locally.



http://ecx.images-amazon.com/images/I/417EF3HMGCL._SS400_.jpg

jsilas
05-10-2008, 09:44 AM
This thread has a fantastic paint-chip repair process documented with photos and all. Hope it helps...



http://www.autopia.org/forum/guide-detailing/80224-paint-clinic.html

Gopher
05-10-2008, 12:00 PM
thanks for the guidance and feedback all. I started the process today and will see where it takes me.



I short cut-ed washing the car and just quick detailed the area I was going to work on. I then cleaned using Walmart`s Prep All which I let sit for a minute then flushed with water and patted dry with a microfiber.



Since then I`ve been using my autosharp pen every half hour or so to add additional paint to a select few chips. I have a bunch of them to work on, but wanted to be able to compare the difference at the end.



I couldn`t find meg`s sandpaper locally, but got some 2000 grit 3M wet sanding paper from walmart which I`ll probably try to use tomorrow evening or Monday.

Accumulator
05-10-2008, 04:05 PM
Gopher- If the Walmart Prep is like (regular) PrepSol, you shouldn`t need to rinse it off, it oughta flash/evaporate cleanly.



I`d be *VERY* careful using the 3M 2K. They might`ve changed it since then, but that`s the stuff that was so awful IME that I switched to Meguiar`s/Nikken. The 3M I used wasn`t uniform, and left some "tracers" that were a lot worse than the rated 2K grit.



Mindflux- Yeah, people`s experiences vary with the Langka. Mine range from super to awful (and everything in-between). Interesting about the Mother`s version, thanks for posting that; perhaps it`ll help mainstream the stuff.



KrisMas- Use PrepSol straight. Just pour it on a soft cloth like a MF, wipe it on, let it dwell a while, and then wipe it off (and repeat a few times). I`ve never tried spraying it and I`d want better control than that. It`s not the sort of stuff I`d want to atomize anyhow.

KrisMas
05-12-2008, 08:05 PM
Thanks Accumulator. Tried it last weekend and works great in removing all traces of streaking on the front hood of my car. Squeaky clean without any traces of wax or oil (to my unexperienced eyes).



By the way, how would you know/test that there`s no traces of wax/sealant/oil/etc left on the paintwork? Any proven method?

Accumulator
05-13-2008, 11:44 AM
By the way, how would you know/test that there`s no traces of wax/sealant/oil/etc left on the paintwork? Any proven method?



Good question, and I don`t have a good answer!



I just use the prepsol until I get that squeaky-clean feel, and then I use it again to make sure. I can`t recall ever having a problem but maybe I`ve just been lucky.