Decals are yellowing on an old model. Any way to fix these?

[bh1701]

I've got a model kit I built over 20 years ago. It's not a model car, it's the USS Voyager starship...but this question should apply to any model. The background of the decals are now turning yellow-gold. Is there any way that this can be fixed?

Since it was 20 years ago, I can't tell you exactly how I applied them, but this would be my best guess. Since the model was painted with a flat finish and still appears to have the same finish, I am betting I applied the decals directly to the flat finish. If I recall, isn't it best to apply decals to a smooth gloss surface, and then spray a flat clear over them if that's the final finish that's needed? While this knowledge won't help me with my current situation, it would be nice to know for future kits.

So, is there any magic solution to my yellowing decals?

Thanks,

Bart

 

[Casey]

 

[Snake45]

Putting yellowed old decals in a window with sun exposure will usually bleach the yellow out. I've never tried it with applied decals on a model, but it MIGHT work. Just make sure the room where you're doing this is cool--might not even be a bad idea to set up a fan to blow on the model as it's sitting in the sun for the several days it will take. (Better safe than sorry.) 

Or it might work to set the model on a porch or patio outdoors in direct sunlight, if you have a place where it won't be stolen or blown over or damaged by neighborhood squirrels, cats, birds, etc. (Got something like an old hamster or bird cage you could put over it.)

[Jim N]

Bart, it is always best to apply decals to a smooth gloss surface.  If you require a flat finish, then use a flat coat afterwards.  The reason for this is that a decal may not completely adhere to a flat finish, and what can happen is that the light goes through the clear carrier and then bounces off of the model and then it hits the back side of the clear carrier.  This causes a "silvering" effect.

As far as the yellowing, it kind of depends on what caused it.  Some decals like paper can yellow with age.  If this has happened I am not sure what you can do other than what Snake suggested.  The other thing that can happen with older decals is that the glue can age an cause this problem.  You can see this on the race car above.  If this has occurred, there is likely nothing that can be done about that.