Removing runs in Single stage acrylic

[IndyCuda]

I painted my engine bay today with a single stage acrylic enamel and hardener. It is a solid with no pearl or metallic. It turned out really nice. I do have a few curtains (runs) about 1/8 maybe 1/4 wide on the passenger side inner fender. I did a brief search and found an article from a body guy on removing them. He said to use a razor blade held at 90 degrees and slowly remove the run until it is very close to smooth with the surrounding paint. Then wet sand with 1000 followed by 1500 then 2000.  You are then supposed to buff it out with a buffer and polishing compound. Everything sounded pretty basic except for the razor blade part. Has anyone done this or have a better way?

[67vertman]

Eastwood sells a tool that shaves runs.  I used it on my car about ten years ago and it worked great, and I used the other steps you discribed.

[72bluNblu]

The razor blade trick works better when the paint is nice and soft. You want it to have a "rubbery" consistency, hard enough so it cuts smooth but not so hard it will chip. Once it sets up hard you can just sand it down without cutting it first, I just use a small, tightly rolled piece of sandpaper to knock down the run without getting too much of the surrounding paint. But don't use the rolled up piece too long, otherwise you'll sand a low spot into the paint. Once you get it close just block sand a small area, I usually start with 1200 and then use a progression of finer grits up to 2000.

[360 'CUDA]

 

Some 1200 or even 1500 on a paint stirring stick cut to maybe 6 inches or so.  Then some rubbing compound and a quick buff should handle it.

[torredcuda]

Put a piece of masking tape over the edge on both ends of a razor blade leaving the middle part of the edge exposed and carefully "shave' the run.This leaves the edge slightly above the rest of the paint but shaves down the run,then wet sand and buff. 

[IndyCuda]

Put a piece of masking tape over the edge on both ends of a razor blade leaving the middle part of the edge exposed and carefully "shave' the run.This leaves the edge slightly above the rest of the paint but shaves down the run,then wet sand and buff. 

The problem is the car is about 40 min away at a relatives. I won't be able to get back over for another couple of days. The previous post said to do it will it was still semi soft. If it is fully cured, or very hard do you skip the blade and just begin sanding with a heavier paper?

[72bluNblu]

If its going to be a few days I'd just sand it. Start with 1000 or 1200 and use a small piece folded or rolled up to work just the run at first. But like I said you don't want to use the small piece too long, or you'll sand a low spot into the paint. The small piece of stirring stick with some paper folded over it sounds like a neat trick. I'd just be careful to secure the paper so it doesn't fall off.

[IndyCuda]

I have another dumb question!  I know, you can't believe it!    It's a single stage with no clear coat. So as long as I don't sand through the color it will buff out and look nice or will it be noticeable if I do a good prep before buffing?

[wedgehead5000]

The razor blade work great on cured paint. You are actually just scraping off a very small amount when you go across the run I use this method whenever I get a run in a flat area. Make sure you use a new blade

[wildbill62]

Put a piece of masking tape over the edge on both ends of a razor blade leaving the middle part of the edge exposed and carefully "shave' the run.This leaves the edge slightly above the rest of the paint but shaves down the run,then wet sand and buff. 

Very good advice! I am a painter, have been for 30 years,

[elitecustombody]

there are few different methods on removing sags,runs and trash on painted surfaces, I'd rather have cured and hard paint to do this,because it's easy to gouge it when it's soft, as mentionned before, there is a tool that's made for this job, Steck makes a few different versions,curved and flat, if using a razor blade,I'd lay two pieces of masking tape on either side of a sag to prevent goiging or digging into area around it,plus it helps to have it as a guide,you can also use 320 grit to sand it down to the level of the tape, then wrap a 2 inch long piece of mixing stick in 1000 grit to block it out,1200 and finish it to 1500 ,single stage paint buffs very easy and there is no need to sand with finer than 1500 grit  

[ShelbyDogg]

I saw Kevin? on the TRUCKS tv show on Spike tv do this with a razor blade.   Here he is on Youtube. showing how to do it.

I just love youtube.....    Sometimes I just have to watch somebody do something once, then I'm off and running.

Part1

http://www.youtube.com/watch?v=hi7LT0OBOis

[Eastwood Company]

That razor blade trick is a good one!

Here is our nib files mentioned earlier if anyone is interested. 

http://search.eastwood.com/search?asug=nib&w=nib+file&p=Q&ts=custom?srccode=cuda