I am having problems with the two halves of the fish rep bonding together. I am use a gel coat them first and then use fiber chop to reinforce a resin layer. The main problem I am having is that the casting resin I am using is not setting up in 12 hrs. The product I am using is 303 from LBI Industries. I am getting frustrated. These are my first attempts, so any help would be greatly appreciated.
Brian
The 303 resin from LBI is a clear resin isnt it?
"303 CLEAR POLYESTER CASTING RESIN
A clear polyester resin designed for encapsulation that may be poured into molds
or over horizontal surfaces, such as tabletops. Ideal for artists and hobbyists."
If thats the case clear resins are normally more twitchy and need more time to set up, also more hardener will need to be added. The 303 is an encapsulation resin meaning it is designed to set in thicker amounts. The thicker amount will mean more heat and less hardener needed to prevent yellowing and cracking. If you are using it in thinner amounts it will probably need more hardener.
Once it passes a point and it hasnt set it wont set properly.
I would probably use 301 resin if you could.
"301 POLYESTER LAMINATING RESIN
Professional quality, premium production grade, general purpose orthothalic laminating
resin. Contains no wax for best adhesion between layers of fiberglass laminate thereby
eliminating the need to sand between layers. Always fresh!"
I have problems when I try to use gelcoat also
I have had issues with the Gelcoat from WASCO and other taxidermy companies. I would order it directly from a supplier such as US composites
Nothing against the suppliers but it inst used much and not often ordered so it tends to sit on the shelf longer then it should. Any Gelcoat over 6 mo old is questionable.
I personally have been using thinned bondo and polyester resin, but will use Gelcoat when I sell blanks. Most customers want a snow white finish on blanks....I dont care either way so...
Also I am facing with a similar problem!!!!
In Joshua Knuth video/page "Molding and Casting a White Crappie the Final part (The Casting)" he said:
"After the resin inside sets yet is still pliable I start to open the mold"
How to know this moment?
My resin hards more or less 4-6 hours.
Now the problem is demolding a 13 lb/25 in open mouth snook. With the small ones molds is easy to know and demold when is pliable but with this... four trash castings!!!
Is there any problem if the cast is setted totaly? no rubbered? no pliable? That I would be sure.
I solved other mistakes like trimming the large edges and smooting the internal angles, even the small scales.
See the pictures:
You should be able to take it out at any point after it is set, its just easier and less stressful on the mold and blank if its still warm. Normally you can tell by the resin oozing out of the seams when its ready.
I shot you a PM about it a little bit ago.
Looking at your top photo I can see where your casting has pulled away a bit from the mold (noticeable on the bottom of the fish)
I would try to run your gelcoat or base coat up onto the seams a bit to help hold that in place so resin doesnt seep under the casting and mold.
You will have more flashing to remove from your blank but it will give you better results in the long run.
I found this picture on the net!!!
Any one could say us.... what product is that
could I prepare some similar material with any resin or other thing?
Thats solve the joining halves!
That product is most likely resin with lots of fiberglass fibers embedded and some thickener to form a paste.
You can get the same results by adding Fiberglass chop to your resin right after you add your hardener. You can also add cabosil to thicken it. I actually use a special dust collector when I grind my fiberglass. Then save this dust to add to my resins to thicken it. (Wear a respirator)
Same basic results of cabosil.
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