What i am doing wrong (need your help badly)!!!

Please look at the picture, the paint goes off with the masking tape. White Tamiya Primer and Tamiya X-28 enamel. The same thing happened with the body. I am so disappointed in myself. Please tell me - what is my mistake? http://evo6.sitecity.ru/album_2512172139.phtml?pix=10

It looks to me that you didn't slice the paint before peeling off the masking tape. Use a very sharp knife, cut the dried paint along the edge of the tape. That should prevent the problem next time.

In my experience I never had to 'slice' the paint as long as I removed the tape before the paint was completely dry. And it's also important that you remove the tape correctly. You need to peel it in the direction of the paint that was just applied ( if in your picture you just applied green and the mask was above the green, then remove the tape in a downward fashion. My father worked in an auto body shop and he told me that peeling off the tape correctly is just as important as putting it on correctly. However, Hirofkd might just as well be more right than I. Either way, food for your thoughts. Better luck next time and hope something works out for you.

I agree with spidereddie. It's wise to remove the masking tape before the paint has dried. I also agree that messing about with a sharp knife along the paint line seems like a recipe for even more disaster.

Another thing you might try is to separate your two colors with a light coat of clear as explained here http://www.cifesystem.com/paint-hint.html (almost at the end) and, I believe, in our famous FAQ.

Your paint job looks quite excellent except for the tape issue.

Actually, I was always taught NEVER leave the tape on longer than you absolutely have to in order to prevent flaking.

Also, don't apply fresh tape to the paint. Take a large piece of plexiglass and stick your tape to it lightly prior to masking. It'll maintain enough stick to hold it to the model body, but won't adhere tightly enough to the paint as to pull it off.

Another thing, use Tamiya masking tape (if you don't) because any other that I tried stick to much and cause this kind of problems, the only important thing as everybody told you is to remove it on time, do not let it dry, but be carefull when you remove it not to damage the fresh colour.

Thank you friends, i'll try to follow your steps. But you know i tried to slice the paint with Exacto knife, but it was going of iven from that. SO it absolutely didn't stick to the primer. I suppose the problem is that i have primered the body and left it for two months (had no time) and probablu some dust covered the model and here we are :(

i tried to slice the paint with Exacto knife(
Don't do that.
SO it absolutely didn't stick to the primer.(
Bummer! Tamiya primer is supposed to be the very best. The upper coat should have stuck to it without any trouble. As we said before, if you remove the masking tape (carefully) before the upper coat is dry it should be OK. Let the upper coat get surface-dry for 10 minutes (in a dust-free place) and then start removing the tape.
I suppose the problem is that i have primered the body and left it for two months(
I don't think so. The longer you leave any level of coat (primer before mist coat, mist coat before wet coat, wet coast before polish) the better - I think?
Thank you friends(
You're welcome.

mmmm "i have primered the body and left it for two months"

Maybe besides dust it got finger grease from handling... did you wash it before applying the green? Grease can prevent enamel paints to stick correctly. Remember that mate paints are more propense to present that problem and tamiya primer is... mate, well maybe that's what happened IMO you can find in the FAQ ways to wash your models before painting them it's worth a look!

No, no i know everything about washing and all the preparations, i am not a newbie. That is why i was so amased - it happened with me for the first time. I suppose the best way is to remove the tape after 10-15 minutes, but i left it till the morning. But there is still one BIG problem. After i applied green to the body and let it dry for several days, i had to mask green areas to paint the rest in black (It's Castrol Mugen NSX) and i found out if i remove the tape (Tamiya masking tape of course) the green paint goes off with it in some places. I suppose i should have sprayed clear coat over the green to prevent it :(

"I suppose the best way is to remove the tape after 10-15 minutes, but i left it till the morning."

that's your problem. Peel off the masking tape before the paint dries!