Masking Problems

I am suffering problems while trying to mask a color scheme. The masking line is sharp and good, but the masking tape seems to "suck" the underlying paint in same occasions:

http://www.sh-modeling.de/forums/IMG_0415.JPG http://www.sh-modeling.de/forums/IMG_0417.JPG
http://www.sh-modeling.de/forums/IMG_0418.JPG http://www.sh-modeling.de/forums/IMG_0419.JPG

I've painted the white at first (over primer) then after 24 hours masked and sealed the edges with clear. After that I sprayed the blue and left it on for one day. Today I removed the masking tape and this appeared :-(
I used Tamiya Masking tape and also Tamiya acrylic paints (the little bottles X-/XF- something) through an airbrush...

Any ideas? Did I had to wait a bit longer before masking?

I think you should have waited longer, probably about a week i would say.

You do not mention what types of paints you are using. I always wiat at least a week before masking on top of another color. It almost looks like the clear you are using is reacting with the adhesive in the tapeCan you give us a little more information on your paints.

Also try to take off the mask when the paint tacks up. What kind of tape are you using?

If you used water to thin the paint you should have waited longer before masking and spraying the blue. Also try to remove the tape a few minutes after painting the second color, but very carefully.

You do not mention what types of paints you are using.

Yes he does.

I've had the same problem with Tamiya gloss acrylics - but not as severe as yours. You need to let the paint dry for much longer than 24 hours before masking otherwise the tape will leave impressions in the paint. I found that even 1 whole month was still not long enough - which is why I've given up on Tamiya gloss acrylics for car bodies. See other threads on this subject. One guy even said his paint was still soft after one year!

I also experimented to see if the length of time that I left the tape on made a difference. It didn't. Even putting tape on for just one hour was enough to mess up the underlying paint.

What happens if I try to use other than Tamiya's masking tape? Maybe it's related to the kind of "glue" the masking tape uses (beside longer drying time)...

Nasty. I've had something similar happen when masking and painting lacquers. Only very minor though, nothing that bad. I could only come to the conclusion it was something to do with solvents leaking/leaching under or through the tape. Haven't found a satisfactory solution as I was able to sand and polish the blemish out. Maybe if it is solvent related, it might be worth trying thinner, dryer coats?

it is the acrylic paint it needs a least a week to dry properly if aplied thinly, it also will chip when dry i suggest you change to tamiya ts range for car bodies and you will not be dissapointed. Cheers Bob.

There are several potential problems here, no telling exactly what happened.

Acrylics sometimes never dry to the point they can be trusted to be in contact w/any other item. A model painted years ago in some acrylics will be damaged if wrapped in a paper towel. This is why I do not paint exteriors in acrylics!

Even if the underlying paint is fully cured, the taped area could be affected by solvents from the paint being sprayed. The solvents can leach through the tape. Doubtful w/acrylics though, but perhaps the clear may have some blame.

Never, ever leave the tape on longer than it takes for the paint to initially set up. You are asking for problems w/the tape attacking the paint underneath, and pulling either the paint underneath or the new layer of paint off when removing the tape. When I do a two-tone like this, I set the body aside or in my dehydrator, clean up the paint area, then go and carefully remove the masking. As long as the paint isn't still wet, you can remove the masking when it's started to set up.

What happens if I try to use other than Tamiya's masking tape? Maybe it's related to the kind of "glue" the masking tape uses (beside longer drying time)...

You're using Tamiya masking tape and Tamiya gloss acrylic. If Tamiya's own tape doesn't work with their own paint then I wouldn't expect any better results with some other brand of tape. Tamiya's tape is supposed to be the best anyway.

On taking another look at your pictures, I can't tell if the bubbles are the white paint or the clear. I've sometimes had a similar bubble effect caused by the clear bleeding under parts of the tape which I didn't burnish down properly. But, again, nowhere near as severe as this. I assume that you are using Tamiya acrylic clear?