Rockchip blob repair

[subjectzero]

I washed and dried my car last week, decided it was time to do something about the rock chips on my car and got out the paint pen. A four year old could have don a better job. I tried to smooth it out as much as possible but now I have small blobs. My plan is to invest in the dr. colorchip repair kit mentioned on the site and it looked much easier to work with. In the mean time I want to get rid of the blobs. I know sanding will be involved, what grit should I use? Anyone have a particular sanding product they recommend?

[BS MXRacer]

Re: Rockchip blob repair

Any sanding experience? Rotary buffer experience? Most sanding marks can't be removed without the use of a rotary.

[subjectzero]

Re: Rockchip blob repair

Not a great deal of experience but I do enough hobby projectsto have a firm understanding. I do have a rotary buffer and have managed to not mess up the paint yet. (knock on wood)

[Michael Stoops]

Re: Rockchip blob repair

If you're going to dive into this then take it very slowly. It's a good idea to put some masking take around the chip, leaving maybe 1/2" - 3/4" clear area between the touch up blob and the tape - this will confine the sanding to a very small area. Now get some 1000 grit and 3000 grit sanding media, soak it in water (preferably overnight) and wrap a small piece of it around a small block to give it support. Keeping the area wet, lightly sand the blob down to where it's even with the surrounding paint - or as close to even as it'll get. Do this first with the 1000 grit, then follow with the 3000 grit at a 90 degree angle to your 1000 grit strokes. Now pull the tape and get some Ultimate Compound or even M105 to buff out the sanding marks. Try it first by hand with a foam wax applicator pad and a good bit of passion. You may need to hit it 3 or 4 times, but concentrating on this very small area of 3000 grit sanding marks you should be able to clean it up. If not, go get your rotary and use the same liquid as used above, but with a foam pad made for use on this tool. Start out slowly, maybe 1400 rpm, and don't use much more pressure than just the weight of the tool. Take your time - it's a new car and as bad as that stone chip is, it's still better than burning the paint by aggressive buffing with a rotary. Keep the tool moving, don't let that pad spin in one place for any length of time. Check surface temp often by simply placing your bare hand on the area - if it's getting really warm, back off and let it cool down.

[mattya802]

Re: Rockchip blob repair

So passionately working UC by hand/DA should be able to remove light 3000 grit sanding marks?

[Michael Stoops]

Re: Rockchip blob repair

So passionately working UC by hand/DA should be able to remove light 3000 grit sanding marks?

That is going to depend quite a bit on the paint but in a very small area you should be able to, yes. You'll also need a pretty clean sanding mark though.

[mattya802]

Re: Rockchip blob repair

I've got soft Honda paint. It'll be on a pretty inconspicuous area and yes, it will be a small area. Just a touch up, not wet-sanding the whole car.

What do you mean by "clean" sanding mark?

[Michael Stoops]

Re: Rockchip blob repair

What do you mean by "clean" sanding mark?

Finish off with a fine grit, don't do it barehanded (a block of some sort is important), keep the area wet and don't let any crud build up in the sand paper. And start with quality sandpaper so that the sanding marks are as uniform as possible to begin with. Granted, you're just doing a very small area, but every little bit helps.

[mattya802]

Re: Rockchip blob repair

Alright thanks for the advice

[subjectzero]

Re: Rockchip blob repair

Wow great tips! I was definitely going to tape off the area. Now I just gotta find some 3000 grit paper. The most the local hobby shop carries is 1250 I think. Thanks for the advice!