So I have some general purpose fiberglass resin

[Haynie]

It needs to get used, and we aren't doing any more fiberglass work, and would hate for it to go bad, so I guess I should use it for something fun. Would it be able to be used to cast blanks?

 

[ldb2000]

See this post http://www.penturners.org/forum/showthread.php?t=81113 , it's a couple of posts below yours .

 

[Haynie]

Saw that and that what made think when I saw it. This not that kind though. I assume gen purpose is gen purpose right?

Now just need to find the time and pigments

 

[ldb2000]

Yep General purpose is what is used for fiberglass work , it's not normally used for casting but will work . It doesn't turn exactly like the clear resin and due to the color will only work with darker color pigments . Michaels has pearlx which will work or if you don't mind mail order www.coastalscents.com has mica pigments (same thing as pearlx but cheaper)

 

[soligen]

IT seems to set faster than the silmar with the same amount of hardener. Try a few small pours to work out the hardener qualtity.

I do silmar at 4 drops per ounce, but when I went to use up some old fiber glass resin, this 4 drops caused the resin to set too fast for me, so I went down to 3 drops for my final pour. YMMV

 

[Sylvanite]

Casting resin is formulated for thick pours. Resin made for fiberglass layup is indended for thinner application. The promoters (such as cobalt napthanate) used may be different types and quantities. The amount of hardener (e.g. MEKP) needed may be different.

Pour thickness is an important factor in the amount of heat produced while curing. If you try casting with a resin not mixed for that purpose, I'd suggest letting it cure someplace where a runaway exothermal reaction won't be dangerous.

Regards,
Eric

 

[Haynie]

Try a few small pours to work out the hardener qualtity.

So I am looking to see if it produces a nice rack?:laugh:

I read through the casting articles last night, let me see if I have this straight:

1-figure out how much resin will fit into the mold. Looks like folks are using 6 inch square molds or maybe PVC tubes

2-pour correct amount of resin into a cup and wait for bubbles to rise

3-put hardener drops into resin and stir carefully so no air is introduced

4-pour resin with hardener into mold slowly

5-Put colors into resin and stir them around slowly

Do I have my steps right? I read about pressure pots. What are those for?

 

[ldb2000]

Yes , that is the basic procedure but there is one thing you got wrong . Add your pigments BEFORE you add your hardener while the resin is in the mixing cup , then let the mixture sit until the bubbles have risen to the top and popped . If you try to add pigment to the mold you will never get an even mix . If you are using mica pigments , you will get swirls even though the pigment is fully mixed . Use a toothpick , or your mixing stick , and swirl the resin in the mold every few minutes until it starts to gel . This will take about 10 to 15 minutes depending on how much hardener , how old the hardener is and the air temperature . once it gels it will take several hours to cure , the surface will be sticky , this is normal .
Pressure pots are not needed with PR . If you are doing clear casting it can help with keeping bubbles from forming but it won't help with bubbles created from mixing and pouring . With color mixes if you let the bubbles rise and pop before you add your hardener and you don't introduce any new bubbles when you add the hardener and pour into your mold the pressure pot is a waste of money and time .

Try a few small pours to work out the hardener qualtity.

So I am looking to see if it produces a nice rack?:laugh:

I read through the casting articles last night, let me see if I have this straight:

1-figure out how much resin will fit into the mold. Looks like folks are using 6 inch square molds or maybe PVC tubes

2-pour correct amount of resin into a cup and wait for bubbles to rise

3-put hardener drops into resin and stir carefully so no air is introduced

4-pour resin with hardener into mold slowly

5-Put colors into resin and stir them around slowly

Do I have my steps right? I read about pressure pots. What are those for?