Hi
I have been experiencing paint peeling off with tamiya masking tape when using lacquer paint (Gaia Colors). I did not experience such a thing when I was using acrylic paint. Can anyone tell me how I can prevent this?
Thanks

By the way, it is only for some parts. Most of them were ok.

Stupid question list, just to cross them all off:
Did you prime first?
Did you give the paint 24 hours to cure before you put the masking tape on?
Did you "tack" the tape first on something before putting it on the paint, to take off that first level of adhesive?

Yes, I did them all

Gotta ask, but were the parts cleaned after handeling them. Like right before you went to primer/paint. Sounds like maybe the paint was sticking due to oil or dirt from handeling, had that happen oh so many times.

I guess that's a followup, are we talking plastic or resin?

It is plastic; gundam kit.
I think the surface was clean. I am thinking if it is because I used a sponge to apply the surfacer to create a rough surface and thus the paint does not stick as well as when the surfacer is sprayed normally...
Anyways, I sprayed the coating layer and tried masking again and the paint did not come off.

Paint chipping happens. If the primer comes off leaving bare plastic, then the plastic wasn't completely clean. If it's just the paint coming off and the primer staying, then there was either a foreign particle in the paint, a foreign article on the surface, the paint hasn't cured completely and bonded with the primed surface, or the surface wasn't clean.

Another possibility is that the masking tape is too strong and lifting the paint. I recommend carefully peeling the masking tape off. Another thing to watch out for is if the paint layers are too thick, when removing the masking tape, the paint frays and chips at the hard edges. This is more likely to occur if the paint is completely cured, so if you don't have additional masking to do on top of the masked area, remove the mask about an hour or so after painting to get nice crisp edges.

Thanks!
Speaking of which, I am using droppers/pipettes to transfer paint and thinner; one for each color. I think it is a source of contamination because I reuse the droppers over and over again. What methods do you guys use to transfer paint?

This is way off topic but is it ok to use like cheap thinner for cleaning?

I use droppers as well. Just recently switched to them. Since I've been using them I haven't had a problem with paint peeling like that, except on pieces that I had handled alot before painting.

I used glass droppers that I picked up from my local drugs store. They're easy to clean using lacquer thinner. But since paint thinning isn't one of those exact sciences (each paint bottle doesn't have the same thinned ratios due to evaporation, relative humidity, etc etc) I now eyeball my paint thinning, so I usually just pour directly from the bottle into a clean shot glass and add thinner until I get the correct consistency.

Correct consistency is based on what works for you with your environmental differences, air pressure, spray style, airbrush brand, etc etc. Again, too many factors to use an exact science formula for thinning paints. So this will be experience. The more you mix and paint, the better you get at it. Starting off with droppers to measure is a great way to start and learn. Just make sure you take note of the consistency of the thinned paints that worked the best for you.

Try over thinning, and try under thinning. You will learn from it.

I started with glass eyedroppers, but got so lazy at having to clean them up that now, I just use my Tamiya stir tool. I stir the paint in its bottle, then transfer the paint by dipping and dripping into a shot glass. Easily wipe clean the tool with a paper towel and Kleer lacquer thinner. Now I use the droppers to transfer thinner and thin the paint to the consistency of milk