Color accurate urethane dyes?

[Hip Cat]

Hey, I've browsed around here before but I've finally started making stuff, and I ran into problems, so I'm finally joining and posting a help thread.

I'm aiming to sell my casts at convention artist alleys or online, and I've got silicone molds to make urethane casts with, but the models I'm duplicating each require certain colors. Some of them are one consistent color, so I think it would save me a lot of trouble if I simply dyed their resin the appropriate color. It sounds simple to me, a newbie, but I can't seem to find any large selection of color-accurate dyes for urethane casting, so I'm beginning to think that the common practice is just to paint the models. I'd rather go with something less time consuming, though, if possible, but if I do have to paint them, I have some questions:

I've sanded my models as glossy smooth as I can, with up to 2000 grit sandpaper. After all that work done on the model, I think it's odd that you'd have to scuff up the duplicates to prime and paint them and then sand them again for each little cast, then spray them over with gloss sealer or something. Is that what happens? If so, is spraypaint acceptable to paint urethane casts? I've used clear coat on other projects before, but it was left tacky, or built up and became yellowish. Is it safe to use glossy clear coat on small models?

 

[division 6]

While you can get dyes they usually aren't all that strong so you won't get a color match.
Try Smooth-On.

Props and models usually come in off white or grey and you paint and assemble them.
Many makers use assorted colors as a way to tell their product from a recast (recasters normally just use white resin)
I have or have seen parts in purple, blue, green, pink, orange.
Accept for a solid black Maltese Falcon all the others are more pastel in color.

no matter how good your prototype is you will still need clean up on your parts even if using a pressure pot.
Base coating with a good primer is best, I'd suggest Duplicolor Automotive lacquer.
A few light coats, let it sit a few days to fully cure than wet sand or just buff with a soft cloth.
If you want a glossy finish then a gloss paint, then if really necessary then a gloss coat.