Paint peeling when lifting tape

bmc414

.. I generally stick to Model Master Acrylics which I will slightly thin.  I am trying out Tamiya Acrylics, but am having the same issues.  I always prime, I remove tack from the tape, but no matter what the paint will lift when I remove tape...

What primer are you using?  Are you using Model Master Acryl Primer?  If so, I would avoid that since it's an acrylic also.  Go with a lacquer based primer like Tamiyas.  I tried the Model Master Acryl Primer and found it useless.  Tamiya's spray can primer is great.

-Jesse

What everyone has said.

Adequate surface perpetration & adequate cure time.

Even if you have washed the kit on the sprue, you really have to give it a wipe with alcohol or something suitable just before you paint - wipe it down, let it dry, then paint, not letting a bare finger near it in the process.

Unlikely, but if you are working somewhere where there is anything like aerosol polishes or anything containing silicon being used, this will not help!

I will agree with many who mentioned surface preparation.  Lifting / peeling paint was my nemesis for years.  Currently, before painting, I would soak a model in water w/dish soap for about an hour, rinse, and let dry.  As a further measure of cleanliness, or if the model has delicate parts that would break from scrubbing, I would spray down with iso alcohol and let dry completely. 

Another thing is handling the model after being cleaned.  Once out of the bath, I never touch the model without wearing gloves.  I always have a box of thin powder free latex gloves on hand and never handle a clean pre-painted model without the gloves.  Might be overkill, but since following the above steps, I never had paint lift off a model from tape, even without primer (which I now only use under limited circumstances).    

Since the primer is coming off too then it is likely surface prep. 

Ditto... Personally, I'd stop priming... More often than not, you don't need to do it except on metal parts that will get handled a lot or when using some metalizers...

You need to prime? Then use a primer that will "bite" into the plastic... That's what it's supposed to do.. Hang onto the surface and give the color something to stick to.  I use automotive grades of rattle-can primer when I need it.. It'll also fill the tiny sandscratches left behind, but it need to be wet-sanded with a super-fine grit before you apply a color-coat.  Don't sand it OFF on corners and edges though..

Since the primer is coming off too then it is likely surface prep.  Unless the primer is just not suited for plastic.  I rarely prime but when I do it is either Mr. Surfacer 1200 or Krylon primer for plastic, decanted and sprayed though an airbrush. But, before I paint anything, the models gets wiped down with alcohol. to remove and residue of anything.

Pulling the paint off is an issue I've been dealing with for some time and I agree that the cleanliness of the prepainted model is paramount  . 

 I have found that soaking the new kit while on the spure in a bath of warm soapy water for about an hour, a quick scrub with an old tooth brush and a rinse in more warm water should do the trick. 

 I also have been priming my model with acrylics thinned with acetone.  don't apply the paint too dry, let it cure overnight, and I have found that even the extra tacky masking tape will not lift the paint.

Huh. I've been playing around with a lot of paints and a lot of primer combos since getting back into things this summer. I've had a LOT of stupid problems. But paint lifting hasn't been one of them, except on some canopy frames.

What kind of primer are you using? How long are you letting it cure before you overpaint it? I think I'd probably have to move up to duct tape before I could lift primer off my builds. 

Another thing you might try is clear coating any areas you're masking, then letting the clear coat cure before putting tape down. 

The prime lifts as well as the paint.  I have been using Tamiya tape.  I'm pretty sure from what I have read that I didn't clean the model properly.  I'm going to pick up a regulator as soon as I can, hopefully that will help somewhat. 

I'm working on a relatively inexpensive 737, but need to get this all sorted out before I start my next build, a Hasegawa F-18 that's going to be converted to a CF-18.  I don't want to butcher a $100 kit because I'm still learning what needs to be done.

Thanks for all the help!!

Is the prime lifting too, or just the color paint?  Usually cleanliness of the plastic surface is the issue, but I really do recommend a regulator. Small ones are available in hardware stores for about twenty bucks.  Too high a pressure can make the paint go on very dry. I airbrush with 15 psi for glossy paint, 20 for flats.

The greatest issue that affects paint adhesion, particularly with acrylic paints is the cleanliness of the surface. The bare surface must be absolutely clean and free of oils (eg. from your skin) and sanding dust. Wash your model sprues in warm soapy water and allow to air dry before assembly to remove any mould-release oils. Wash again if practical, or wipe down with isopropyl or denatured alcohol after assembly before applying paint.

Use a low-tack masking tape such as Tamiya's or 3M's "blue" masking tape. If you find the tape is still too tacky, lay the strip down on your arm to remove some of the tackiness.

When removing the masking tape, do not pull straight up at 90 degrees to the surface - pull it back over itself at as low an angle as possible.

EDIT: As mentioned above, you need to leave sufficient time for your paints to cure (not simply dry - eg Tamiya acrylics can be touch dry in minutes) before masking. Tamiya paints that are dry but not cured will lift if you look too hard at them (ok, that may be a bit of an exaggeration) but after leaving overnight to cure, they're very tough.

what brand of tape are you using? tamiya tape is good. Possibly you aren't letting the paint dry long enough. Or possibly surface prep needs to be better. Is the primer coming up too? or is the paint not sticking to the primer?