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Paint peeling from plastic nose cone

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sj_h1

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I found after my 1st flight of my Flat Cat the Fluorescent Yellow Createx paint I airbrushed on is peeling away on the nose cone only. In fact, I could easily rub the rest of the paint off with my fingers. Should I have roughed up the cone before I painted it? Anyone else seen this? :y:
 

DAllen

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Roughing up the cone is probably the biggest thing to do when painting plastic. A 220 or so will be just fine. It seems nothing sticks to some plastics without some degree of sanding. I've even had a hard time bonding epoxy to some plastics without sanding. Also, I have found that using a good (and compatible) primer goes a long ways to a better paint job. I know very little about Createx but I would follow the manufacturers directions exactly to prevent things like this.

Having to repaint something like that is really not a big deal but a pain nonetheless.

-Dave
 

bguffer

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I have read it is generally a good idea to wash plastic pieces with hot, soapy water prior to painting. Maybe you have already done that...

Bob
 

sj_h1

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No, I didn't, but I'll do it if that will help. Anyone else have any ideas?
 

troj

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I have read it is generally a good idea to wash plastic pieces with hot, soapy water prior to painting. Maybe you have already done that...
That's a big key, right there -- it removes the mold release on the plastic.

It's also a good idea to not touch it with bare hands afterwards, as you'll leave oils behind that reduce adhesion.

-Kevin
 

TheAviator

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I've also heard bleach water helps to remove the mold release better than just soap and water, although I recommend following the bleach water with this to make sure all of the bleach is gone.
 

m85476585

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You could also try a primer coat of paint that is designed to bond with plastic, like Krylon fusion or the Rustoleum equivalent in addition to washing and possibly sanding. I don't think they sell Krylon Fusion primer specifically, but you can just pick any color and use that. Flat would be ideal if they make it. I haven't tested this, but it should stick well to the plastic nose cone and provide a good surface for other paint/primer to stick to. It might not work as well with airbrush paints, though, since they are mostly waterbased and don't have solvents to make a good chemical bond with the Krylon Fusion paint.

Another option is Duplicolor Adhesion Promoter, which is a clear primer composed of mostly solvents that you spray on the nose cone before painting with regular paint, but again I think the second coat is meant to be lacquer/enamel-based spray paint, not water-based airbrush paint.
 

Pem Tech

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The best way we have found to paint plastic nose and tail cones is to first, bathe them in hot soapy water. Candles and Barry WHite music optional. Once dry, sand with a corse sand paper like 80 or 100 grit. The deep grooves and raised ridges help the primer adhere to the plastic. Prime and sand the heck out it to make it smooth again. I use 220 and 340 grit during this phase. Once smooth, apply paint as desired.
You milage may vary....
 

RangerStl

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m85476585 I think hit it. Washing the plastic parts is important, but Createx is water-based and does not bond with plastic. You need a plastic-friendly base coat to start. I have painted foam with this exact paint and it will peel off in flakes if you pull on it. It is also very thin and translucent so make sure you start with a white base coat.

N
 
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