Paint Bleed Through Masking Tape. Is There a Fix?

[TheCamaroKid]

I was hand painting the louvers of my Camaro IROC Z model Kit. My Camaro IROC Z is white (matching my real car), and I wanted the louvers black. I covered everything in Tamiya masking tape. I had painted the louvers with lacquer. They came out decent. What disappointed me most was that random black dot on the back of the hood. I'm not even sure how that got all the way over there. Minor runs near the louvers don't bother me, but that's like that Seinfeld episode (the red dot sweater)!

Is there a fix? I'm building this is as a slot car drag car. I'm not sure if I want to strip it down, since the rest of the paint looks great!

[Modelbuilder Mark]

Fine detail areas, I know some people use Bare Metal Foil for the close up area, then tape off a wider area. THEN, despite being an extra step, shoot a light coat of the color behind the tape, in your case the white, around the tape edge, that way  if anything bleeds under, it will be the same color, then when that dries spray your black. For what you already have here, tape of the reverse this time to cover the black, and you may be able to VERY carefully sand away the offending areas. 

 

Edited March 20, 2023 by Modelbuilder Mark

[Lunajammer]

If the paint is still soft you can sometimes carefully, lightly, scrape it off with an Xacto blade. Just not sure in this case if it will leave a shadow on that white.

[TheCamaroKid]

8 hours ago, Lunajammer said:

If the paint is still soft you can sometimes carefully, lightly, scrape it off with an Xacto blade. Just not sure in this case if it will leave a shadow on that white.

I put it away for now. I might buy a second IROC Model kit and try the above guy's spray paint technique. Come back to this project later. Maybe strip it down and paint it all black.

[Jon Haigwood]

Like Mark mentioned , after applying tape spray a light coat of the base color to seal the tape edge. I also will seal it with a clear , I mostly use Alclad Klear Kote 

[ctruss53]

I do not subscribe to painting a layer of the base color first. You will already end up with a "ledge" where the paint builds up thicker than the base coat. If you add another base coat you are just thickening that secondary color coat.

In my experience is to paint that secondary color area in very light mist coats. If you apply the paint light enough there literally isn't enough paint to bleed under the tape.

If possible, another technique that helps is to paint away from the tape edge. Meaning spray at an angle greater than 90 degrees from the surface with the taped edge. If you are painting in light enough coats, this doesn't really matter. And in your case, you can't do this. But it is something to think about.

[Ace-Garageguy]

You can almost certainly fix it by VERY CAREFULLY wet-sanding, right up next to the bleed edge, using a folded over piece of 600 grit, then use a polishing compound to bring the gloss back up.

CAREFULLY is the watchword, but I've fixed stuff worse than that.  

In the future, you might also consider one of the 3M fine-line green plastic tapes made for real cars. They adhere very well to prevent edge-bleed, are very thin, and will follow curves well. I've used the stuff for flames and stripes on real cars and numbers on real aircraft for decades.

 

[Mark]

The thin tape is the key here.  When you use too-thick tape, when paint is applied it goes not only to the area that was masked off,  it also settles against the "side" of the tape.  Thicker tape = higher ridge created by the paint that settled against the thickness of the tape.

[LDO]

Are you burnishing it down? This was done with Tamiya masking tape, trimmed with an X-Acto knife, painted with Tamiya spray can lacquers. 

Edited March 23, 2023 by LDO
Spelling

[Sidney Schwartz]

On 3/21/2023 at 12:02 PM, Ace-Garageguy said:

In the future, you might also consider one of the 3M fine-line green plastic tapes made for real cars. 

Is this the stuff? I'm not happy with the Tamiya masking tape and am looking for something that works better.

https://www.amazon.com/Scotch-08987-Performance-Masking-Tape/dp/B002C47XMU/ref=sr_1_8?crid=2BA33TT0O8EQJ&keywords=3m%2Bfine%2Bline%2Bauto%2Bmasking%2Btape&qid=1679678492&sprefix=3m%2Bfine%2Bline%2Bauto%2Bmasking%2Btape%2Caps%2C163&sr=8-8&th=1

 

Edited March 24, 2023 by Sidney Schwartz

[Ace-Garageguy]

54 minutes ago, Sidney Schwartz said:

Is this the stuff? 

I don't think so. That's a paper tape, I believe.

3M makes a green paper "fine line" tape (useless to me except for fixturing, jigging, marking hose to cut, etc.), a blue plastic fine-line tape (too thick for me), also I believe a purple plastic fine-line tape (also too thick IMO), and a very thin green plastic fine-line tape.

I'll see if I can find you a product number for the magic green plastic stuff.

EDIT: This is it. It's not cheap, but it's always done the job for me.

   Side CMA note: 3M has had an annoying habit of changing some of their products to perform less well, probably having to do with offshore suppliers, but keeping the same part numbers. If the new stuff doesn't work wonderfully, that's why.

https://www.amazon.com/Scotch-Fine-Line-Green-rolls/dp/B0065GVEZ8

Edited March 24, 2023 by Ace-Garageguy

[Sidney Schwartz]

Thanks.

[Ace-Garageguy]

Just now, Sidney Schwartz said:

Thanks.

Found it, edited the post above.

[Sidney Schwartz]

Ordered it. Spendy, but will probably last a good while. Thanks again.

 

[Ace-Garageguy]

11 minutes ago, Sidney Schwartz said:

Ordered it. Spendy, but will probably last a good while. Thanks again.

 

How's this for a deal?

If you don't like it, if it doesn't work well for you, since I recommended it, I'll buy what you have left over.

[Sidney Schwartz]

That's very nice of you. I'll keep that in mind. Hopefully I'll love it. ?

[Sidney Schwartz]

I'm about to try out this tape. I'm trying to paint a VW Beetle in this style...

For the first attempt I used Tamiya masking tape. I burnished the edges and then brushed 2 layers of clear coat over the edges to try and seal them. The result was so awful that I considered it unfixable and stripped it down to the plastic. It'll probably take me a few days to finish the painting. I'll post the results here.

 

 

[Sidney Schwartz]

Wow! Zero bleed through! There are some other imperfections that are my fault, but this plastic tape worked perfectly. Thank you Ace-Garageguy. ?

[Sidney Schwartz]

Here's a better pic now that the clear coat is on.  Looks great!

[Ace-Garageguy]

On 3/30/2023 at 5:02 PM, Sidney Schwartz said:

Wow! Zero bleed through! There are some other imperfections that are my fault, but this plastic tape worked perfectly. Thank you Ace-Garageguy. ?

Glad it worked for you. It's never let me down yet.