Wet sanding raised touch up paint on BMW

[slapshot]

I am going to start the full detail of my wife's 335i next weekend. There are a couple rock chips that had touch up paint put on them and they are raised. I know the BMW touch up paint is lacquer, so I'd assume it will be pretty hard. One spot is very noticeably raised and will take some sanding.

My plan is wet sanding with 1000, then 1500, then 2000 on the high spots. After sanding, I'm going to rotary buff with Finesse It II, then start the full polish & wax (Pinnacle ASR and AFP, WDGPS 3.0, ended with Pinnacle liquid Souveran).

Any other ideas on getting those high spots down? I was considering making a very small block to keep the sanding of the surrounding area down. I'll also tape off the area to prevent over sanding the regular paint around it.


Thanks!

 

[andrew b]

I wrote up a chip repair using the BMW touch up paint, I hope it's ok to post this link here since it's not a detail supply forum (and I even reference Autogeek! ). Shows pretty much step by step what I did, with photos.

DIY: Wetsanding paint chip repair - Bimmerfest - BMW Forums

I have had good results using the BMW touch up paint and light wetsanding. I do use Dr. Colorchip for smaller rash where I'm not as concerned about gettign the paint surface level.

 

[KneeDragr]

I believe there is another system, Lanka or something like that, where it fills in the chip flush with the rest of the paint. Im going to give that a shot next time as I ran out of my Dr. Colorchip kit.

 

[swanicyouth]

This is an excellent write up. I have a chip on my hood of my M Roadster I just hate. I fixed it the best I could with Dr ColorChip, but its not perfect. Dr CC isn't great for a chip. I haven't the balls to attempt a wets and on my hood. I've never really done it before and its not the place to learn. Wish I could get a cheap old panel.

 

[andrew b]

I believe there is another system, Lanka or something like that, where it fills in the chip flush with the rest of the paint. Im going to give that a shot next time as I ran out of my Dr. Colorchip kit.

Langka works pretty well, I've used it as well. it's definitely an option if you don't want to take on wetsanding.

 

[Mike@DedicatedPerfection]

Fantastic article that you put together. I have a few chips to take care of on my cars and have the Dr. CC kit.

 

[BobbyG]

Tremendously well written article Andrew....Definitely one for bookmarking!! rops:

 

[slapshot]

One last question. My local store was out of Finesse It, so I got some Meguire's 105 and 205. After the sanding (ending with 2000), I plan to use the 105 the get the scratches out. Do you think the 205 will be needed also, or should I be ok with going right on to the Pinnacle ASR and AFP?

Great info posted so far, thanks much!!

 

[Mike PhillipsMike Phillips is verified member.]

Any other ideas on getting those high spots down? I was considering making a very small block to keep the sanding of the surrounding area down. I'll also tape off the area to prevent over sanding the regular paint around it.


Thanks!

Here's another option...


How to use Meguiar's Unigrit Sanding Blocks to remove runs and dirt nibs in paint


How to remove a run or paint sag
To remove a run, you want to use the side of the block and only sand on top of the run. If the run is thick, you can place tape on the sides of the run to prevent you from sanding on surrounding paint while knocking down the run. At some point you'll have to remove the tape and at this point focus on the task at hand and hold the block in such a way as to only sand on the high points of the run.

Back and forth direction
Holding the Unigrit Sanding Block firmly, use a fast back and forth motion to sand the run down flat.

Use fingers as a guide
On the panel below, the run was just below a raised body line. The run was too close to the raised body line to use tape to cover the body line so instead I placed my fingers on the raised body line and used my fingernails as a guide or bumper to prevent my hand motion from running the sanding block over the paint on the raised body line.

Here I've sanded just a little and then stopped to take this picture as the sanding marks have made the run easier to see and capture on film.

The section above was sanded flat and then the sanding marks were buffed out using a compound and a wool pad on a rotary buffer. Next I continued to move down the fender sanding the run flat.

After the majority of the run has been sanded flat I re-sanded the entire area using a Meguiar's 3" #3000 Unigrit foam backed sanding disc on a Griot's Garage 3" Mini Polisher to refine the sanding marks left by the Unigrit Sanding Block to a more shallow depth to make removing faster and easier and without generating as much heat.

Here's another run sanded flat using a Unigrit Sanding Block

Here's Robert DiTerlizzi of Impressions Fine Detailing sanding out a run on the high side of the rear fender body line.

After sanding the run flat Robert will dampsand using a Meguiar's 3" #3000 Unigrit foam backed sanding disc on a Griot's Garage 3" Mini Polisher and the buff the area using a compound with a wool pad on a rotary buffer.

:xyxthumbs:

 

[brentech]

My own post from my problem thread: http://www.autogeekonline.net/forum...170-paint-abrasion-horrible-touch-up-job.html

Okay, here it is. I think it went pretty well for the most part. Still can be seen from the right angle, but is mostly hidden. Yeah, it's always going to bug me to a degree, but maybe in the future with some different tools at my disposal (just a PC7424XP at the moment) I'll be able to really flatten it out. While I'm trying to keep the car as good as possible, it's not like it's a show car.

Here we are, just taped around it as you last saw it:

Wet sanded to where I felt safe:

Used Meg's 105 on tangerine pad:

More work was still needed towards the top and left side, tiny bit more wet-sanding, then M105 a second time:

Meg's 205 used on a white pad:

A picture using a photography daylight constant as a sun, if not done from the right angle, the metallic in the paint makes it almost impossible to notice:

Opened garage for real lighting and took a few steps back:

Last picture here is centered on the abrasion:

So, while its still there in a bit, the paint did fill with the color. If viewed from the correct angle, you can see it, but otherwise it's not a total eyesore as it was.
I still have yet to re-apply some WG DGPS to it.

Since then, I've reapplied paint and got it even better in my eyes. Mike posted much the same advice post in my thread, so just take your time and work confidently......it works!

 

[andrew b]

This is an excellent write up. I have a chip on my hood of my M Roadster I just hate. I fixed it the best I could with Dr ColorChip, but its not perfect. Dr CC isn't great for a chip. I haven't the balls to attempt a wets and on my hood. I've never really done it before and its not the place to learn. Wish I could get a cheap old panel.

Fantastic article that you put together. I have a few chips to take care of on my cars and have the Dr. CC kit.

Tremendously well written article Andrew....Definitely one for bookmarking!! rops:

Thanks guys! I actually wrote it as an email first for just a couple people in the BMW community, who aren't (quite) as into detailing as we all are, and they kept after me to post it in that forum. Was a bit timid to post it here since I'm pretty low on the learning curve compared to many of the folks here.......but glad you like it

Those unigrit sanding blocks look awesome - I need to get some!

 

[Mike PhillipsMike Phillips is verified member.]

Since then, I've reapplied paint and got it even better in my eyes. Mike posted much the same advice post in my thread, so just take your time and work confidently......it works!

Nice addition to the thread Brent...

:dblthumb2:

Thanks guys! I actually wrote it as an email first for just a couple people in the BMW community, who aren't (quite) as into detailing as we all are, and they kept after me to post it in that forum.

Was a bit timid to post it here since I'm pretty low on the learning curve compared to many of the folks here.......but glad you like it

We're glad you did, we keep this place friendly and always helpful... just try to find a forum where you'll get better help with tons of pictures, videos, links etc., instead of one-liners...

Those unigrit sanding blocks look awesome - I need to get some!

It's all about the right tool for the job and sometimes they are the right tool for the job...

 

[slapshot]

Thanks brentech, that's about what I'm up against. One spot is a little higher than yours.

I ended up buying some M105 and M205, so I think I'm all set to start it Sunday. I think this will end up being a 2 day detail job. But hey, I'm on vacation all week.

 

[Andr3wilson]

Personally I have hard a ton of success with the Lanka system on small chips; roughly the size of a pen tip.
Larger chips, it works ok, but can still leave a noticeable dimple in the paint.
Wet sanding is necessary to make it perfectly level.

Seems like you're in excellent condition to fix it up yourself!