Casting Newbie (Long)

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rjwolfe3

rjwolfe3

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Mansfield, Ohio, USA.
:bulgy-eyes:Ok, so I decided to jump into the world of casting. Can't afford a pressure pot yet so I am casting without pressure. I got all the stuff together over the last few weeks. For now the molds I am using are around 4"x6"x3/4". I am using around 12oz of PR. The first cast I did had 1 ml of pearl-ex mixed in and I added 48 drops of hardener. Poured it in my mold and let it sit. The second cast my wife wanted to be multicolored so I put 1 ml each of 2 different colors. (Unfortunately they mixed into kinda of a dark silver so that didn't work!:hypnotized: Any ideas on how to swirl two different colors to keep them seperate?) Put the same number of drops of hardener and let it set. Came back 24 hours later and the first cast had little pools of pr on top that did not harden but the second cast was rock hard all the way thru. Any idea of what I did wrong?:at-wits-end: Same pr, temp, humidity, time, hardener, mold size. The only two things I can think of are either I didn't get the hardener all the way mixed on the first cast or using 2 ml of pearl-ex makes a big difference. Is there anyway to dry the rest of the pr on the first mold quickly or do I just leave it set for a few weeks? Also what kind of liquid dyes or paint can be used with pr?

At the same time I decided to try some Alumilite. I poured equal amounts into two different cups. I added 1 ml of pearlex to each cup of the same color. I mixed the pearlex in and then poured the two parts into my mold and mixed that up well. Wow does that dry fast.:eek: I think it was rock hard within 5 mins. But I noticed there is still some liquid remaining after several hours. Is that normal? Also I didn't relalize it would turn white when dry. Is there different colors available? Am I doing the steps right on this or is there a better way?:question:

Thanks for reading thru this and for any advice you can give.:worship: I will try to get some pics taken and post here so you all can see what I cast.
 
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Rob

On the first, try setting it out in the sun or if you have a small toaster oven that you're never going to put food in again, bake the brick a bit.

On the second, did you mix your second color into the same cup as the first color? - should be two different cups, hardner in each cup, then pour into same mold.

On the third, most 50/50 instructions have you mix the two components together well in a cup before pouring into the mold.

Others will have thoughts too... good luck
 
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I have used acrylic paints in Pr with no problems so far.

Like TD said on the mixing of colors. you need to prepare them seperately, then pour them together and just swirl them with a toothpick or popsickle stick. But don't over swirl or they'll blend too much.

I have noticed that some colors seem to be more or less dense than others so you may still get some movement after you swirl. Check back in 5 minutes or so and see what the top looks like and you might swirl again if it hasn't hardened.
 
First, what's become my standard reply:

1) Visit the library and read the casting tutorials
2) Check out Grub32's video's on YouTube
3) Visit my Color library for info on pigments, ratios of hardener/resin, and temperature/gel times.

As always, the library is open for new recipes.

Then:

On your 1st cast, did you mix the hardener in a cup then pour, or mix in the mold?
You should be mixing in a cup then pouring.

In your second unswirled-swirl, it sounds like you poured them together too soon. You want
them to be almost gelled before you pour. Last swirl I did the bottom of dregs of the pour
gummed to the cup, leaving a thin coating because it gelled as I poured. Made a great swirl.

I've not done alumilite, so I'll leave that to others.
 
Thank you all for the replies.

I put the cast out in the sun. Its about 75ish out there so I put it in full sun. Hopefully it will dry up fast. Been looking for a used toaster oven to add to the shop. Maybe I can convince the wife to get a new one, lol.

Now I know the secret to two color blanks. Next time I will divide the pr and colors.

I was worried about mixing the alumilite all together in cup because of how fast they said it set. This stuff started setting up in about 60 secs.

Will be looking at acrylic paints next.

Jason, the wife and I were looking over your color library. I really like some of the color variations. If any of mine turn out descent then I will send the recipes to you.

I think I have printed off and read just about every article I can find on casting and I was able to save all of Grub32's videos to my computer. (I tend to read and research more then do, which is why I get very little done.)

I did mix the hardener in the cup before I poured it but I may not have mixed it long enough. Is there a set time to mix before pouring in mold?

Thanks again for all of your help. I will be saving all of this information to look back at later on.
 
rjwolfe3 said:
Thank you all for the replies.

I put the cast out in the sun. Its about 75ish out there so I put it in full sun. Hopefully it will dry up fast. Been looking for a used toaster oven to add to the shop. Maybe I can convince the wife to get a new one, lol.
Click to expand...

I put mine out on top of my black trash can, under a clear juice jug that's had
the bottom cut out. Probably around 200F under there. But then it's 100F everywhere here.


Will be looking at acrylic paints next.

Jason, the wife and I were looking over your color library. I really like some of the color variations. If any of mine turn out descent then I will send the recipes to you.
Click to expand...

As far as the library goes, there are no bad colors.

Especially if you use pigments I haven't used (hint to all you powdercoat and acrylic users), send them
in anyway. I'm also way short on low-temp data for gel times. (It's still over 100F here during
the day). You don't need to make a chip and scan it like I do- a picture works (see recipes 60 and 61
for a couple from GlassScratcher).
 
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According to ETI the Castin' Craft guys mixing time for MEKp into PR should not be less than 60 seconds....scraping the sides of the cup and both sides of the stick frequently.

The brick will eventually cure. Although I do have a brick I cast back in June that I can still bend.... but we don't need to go there!
 
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