what can i add to tint polyester water clear resin?

zorg

Master Member
RPF PREMIUM MEMBER
as the title says. trying to create a clear yellow resin.

i have tried tamiya clear yellow, and the resin did not set.

what else could i try?

-z
 

exoray

Master Member
Polyester should be easy to tint, even food coloring should works as the water has minimal effect on polyester...

You can also take some powdered RIT dye and dissolve it in a bit of acetone, filter it through a coffee filter to get rid of any solid chunks and floaters that didn't dissolve and then mix that into the polyester... The acetone in low volume again will have nil effect on the polyester setting up, even in high volumes it will simply give the polyester a more rubber like cure vs brittle hard...

But, if you want something more 'pro' hit up Michaels, Hobby Lobby or the likes and get some Castin Craft resin pigments, they have translucent and opaque...
 

Laser Brain

Sr Member
Really? I have found that water/moisture has a very negative effect on Polyester resin, causing it to either reticulate (at best) or preventing it from curing completely. That is why I seal clay with silver nitrate (vinyl spray) before letting polyester anywhere near it.
 

exoray

Master Member
Really? I have found that water/moisture has a very negative effect on Polyester resin, causing it to either reticulate (at best) or preventing it from curing completely. That is why I seal clay with silver nitrate (vinyl spray) before letting polyester anywhere near it.
I have never had any ill effects from minimal moisture exposure with polyester, I use WED clay all the time to cover parts and then shell over it with polyester fiberglass, remove clay and pour silicone in the void... Never a cure issue, I have also used water based acrylic paints to tint polyester without issue...

Urethane on the other hand will go crazy with moisture contamination...

If there are any concerns do the RIT dye and acetone as I suggest, acetone has long been a additive to polyester resin by taxidermist to give it a little flex... You can add huge amounts of acetone to polyester, I have seen people do 4 or 5 parts acetone to 1 part polyester as a soak in wood sealer and it still cures just fine... But you will likely need to filter the powdered RIT dye as there are particles and floaters (as well as possibly other things) that won't properly dissolve in the acetone and will show up if you are doing a translucent casting...
 

Laser Brain

Sr Member
Weird. I have had polyester resin react to minimal moisture from WED clay, more than once, just from not sealing the clay adequately. I've never met anyone who would fibreglass straight onto damp clay.
 

zorg

Master Member
RPF PREMIUM MEMBER
hmmm, thank you for your input guys. i found some of that pigment on ebay of all places.

i might try some of the suggestions, not sure about the polyester and water, never tried or at least don't remember.




cheers

-z
 
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