Molding a Triggerfish, My very First

[arobele]

Hello everybody:

This is my first attempt to do a mold and cast.

Here is the model:

The first three picts.

Molding with playdough for sculpt.

Please, help me to improve with your comments.

[arobele]

The first layer using a very good silicone RTV.

The second one I used a medium silicone RTV.

And after that, I used a cloth with big mesh (in spanish "manta de cielo").

And after three fiberglass layers.

Please, do comments

[arobele]

The same on the other side.

Problems founded.

The RTV silicone application produced bubbles.

I used vaseline for demold... maybe not enough because was difficult for demold.

Or maybe the perimetral flange shuold be other thing like a guide.

I still will do the fish, I am thinking to use fiberglass again.


Please, help me with your experience!!!!

Thanks,
Adolfo

[rnviper3]

did you get a paintable fish with this mold or did the bubbles cause you trouble.

[arobele]

I am trying to do a replica. A fish that I will cast and paint.

The bubbles caused holes.

But maybe I could devast with the dremmell?

Thanks!!!

[Jknuth]

Here is a trick that will help you fill the bubbles.

First take a sharp knife (Exacto) and put a small slice into the sub surface bubbles. This will allow the gas to escape.
Next take silicone caulk and thin is very slightly with Xylol (Do this outside and wear a mask) You will only need a small amount of caulk.
Next use a syringe and needle to inject the thinned caulk into the subsurface bubbles. Gently wipe off the extra caulk immediately.
You can then inject the caulk into the exposed bubbles and carefully clean the area before the caulk sets.

Work slow from one side to the other and fill all of the bubbles you see.
It takes time, but can save a mold.
You may still have a few bumps to reove on the castings, but the results will be much better.

[Dondi]

Arobele,
 I think you did a pretty good job for your first fish mold !
Smaller fish, closed gills & mouth.... good selection.
You will be able to pull a cast from the mold, chase and finish for your replica...
Good Job...looking forward to seeing the finished Replica !

[arobele]

Thanks for your comments.

I will do it!

[Brian Claar]

Not bad for your first.

Here is something that may help you down the road.

Something i noticed right away was how you changed the natural shape of the fish in your bedding material.  I would recomend using High Fiber in the future.  Take great care and more time bedding up your fish so that you don't distort it so much.  This may require pulling the fish out of the bedding material several times until you get it right. 

Cool fish.

[Steve Rotramel (Witchbane)]

You might try a lower viscosity rubber for that first pour, and partially de-air by pouring in a steady stream from one container into another from at least four foot height.  That will get a lot of the bigger bubbles anyway.

Good job!

[arobele]

Thank

Brian and Steve:
I appreciatte your comments.
I did an error bending more... even this was a trial. I will take more carefull to do better natural shapes. Thanks, I will improve in the next ones.


But... "High Fiber"...  I did a research in the site, but perhaps here in Mexico I will no found that. If some one knows, please tell me. I still should be using the play dough.... because trying the Dondi's recipe in http://www.taxidermy.net/forum/index.php/topic,172971.15.html is just for thiker skins fishes.

Thanks,
Adolfo

[Brian Claar]

High Fiber is available through WASCO supply. 

[arobele]

Here is the cast.... Finally!

Please criticize, I would thank you.

Adolfo