casting resin reef safe?

[reiko1078]

does any one know if polyester casting resin is reef safe once its cured? i want to make two disks with magnets cast into it for use as a power head mount or for sticking frags to the walls or for whatever else i can come up with. thanks in advance

[mfinn]

I've been using it for a few months now to make my frag racks.
I know a couple who have been doing just that for a couple years.
I found a thread where Randy Holmes-Farley said once it was cured it was inert.

I found a few other threads where people were using it. I did find one post where a guy said he had a problem with it getting brittle and breaking up. I tried to get a hold of him to find out what type of resin he used, how he mixed it, and any other info he had but I haven't heard back from him.
Other than that one post, there seems to be a bunch of people using it.

[reiko1078]

hey cool thanks

[CoralBananas]

Originally Posted by mfinn

I've been using it for a few months now to make my frag racks.
I know a couple who have been doing just that for a couple years.
I found a thread where Randy Holmes-Farley said once it was cured it was inert.

I found a few other threads where people were using it. I did find one post where a guy said he had a problem with it getting brittle and breaking up. I tried to get a hold of him to find out what type of resin he used, how he mixed it, and any other info he had but I haven't heard back from him.
Other than that one post, there seems to be a bunch of people using it.

I know this thread is old and sorry to revive it but I've been researching a reef safe casting material to use in a latex mould and I think I've finally found the answer here.

So far I've ruled out cement and plaster mixes such as stone powder and plaster of paris etc and ceramic has to be baked so I thought I'd look into casting plastics but there are so many different types and different chemicals used it's a mind field.

From your experience, would polyester casting resin be the top choice for casting ornaments for example? I appreciate any responses.

[mfinn]

I have used Castin Craft polyester casting resin for my frag racks that is several years old now and still in good shape. It holds up very well in saltwater.

[CoralBananas]

Originally Posted by mfinn

I have used Castin Craft polyester casting resin for my frag racks that is several years old now and still in good shape. It holds up very well in saltwater.

Thank you!

Does it sink in salt water once set? I mean its not one of those plastics that floats is it?

[mfinn]

Haven't tried it.
It may or may not.

I always used it attached to magnets and eggcrate

[CoralBananas]

Originally Posted by mfinn

Haven't tried it.
It may or may not.

I always used it attached to magnets and eggcrate

Thanks again, did you ever use any polyester color pigments in the frag racks you made? I want to use some with what I plan to make but I wanted to double check if its ok first.

[mfinn]

Originally Posted by CoralBananas

Thanks again, did you ever use any polyester color pigments in the frag racks you made? I want to use some with what I plan to make but I wanted to double check if its ok first.

Yes, I used a black opaque color.