Simple question, but I can't find the answer

[RTL]

Do I add colorant before I heat the Plastisol or after?

See, told ya it was simple!

[Justin9j]

Before works best.  You can add after its hot if you need to change/darken the color. 

[RTL]

Sweet!

Thanks for the quick reply

Wish me luck!  First Pour coming up!

[RTL]

Ready for the next question?

Can you reheat the plastic after you've heated it?

The reason I ask this is because I seen a video where the person was cycling the plastic through the injector and I accidentally dropped the nozzle into the hot platstic. So, I'm going to have to wait until it's cool before I can get my nozzle back

Did I just ruin 4oz of Plastic?

[andrewlamberson]

Nope..all is good. Pluck that thing out of there (I've done it few dozen....or maybe more... times!) with a pair of pliers or a spoon and  wait for it to cool ....and clean the plastic off it (wear gloves!!!!). You can reheat the plastic numerous times...but depending on the color you are working with...you probably should add some "heat stabilizer". Bottom line...dark colors are easier to work with than light colors.

As a general practice, I add heat stabilizer on the 3rd re-heat. Make sure you are watching your temperatures. The plastic MUST reach 350 the first time you heat it. It will start to "burn" about 400. So....target 360.

Good process ...is the key to success!!!

[pjmcla]

Ah - Yes - The old nozzle in the cup trick.   Been there many times. You will get the habit of holding the nozzle in place with A GLOVED HAND as you inject into a spare pyrex bowl or back into the cup.  I keep a pair of large opening needle nose on hand ( right on top of the micro. ) for just such occasions.  You will get the hang of it.
A few colors are "must add cold" colors.  Clear, high fluorescent colors are and so are some clearer, color changing colors.  Almost all others can be added hot.  Once the initial heat to a consistent 350 degrees has been done and well stirred, gently, throughout the heating cycles; the catalization has taken place.  It doesn't have to be reheated to 350 each time.  Just hot enough to inject well ( 325 - 340 ) depending on the mold.  But; it needs to be stirred well to break up and liquefy all clumps to a perfectly smooth consistency.   Once you clear 300 while heating, you need to go in baby steps ( 15 - 20 seconds each ) until you get the hang of heating time vs temperature change for a given volume of  plastic.  Working with less than three oz. of plastic is trickier and heating cycle times above 280 should be 10 - 15 second max.   These are my observations and routines.  Others may have better advice.

[pjmcla]

OH;  on reheating plastic.  If you watch your maximum temperature closely, and stir gently, but well, on each heat your number of reheats goes up for a given color.   Adding a few drops of heat stabilizer will help hold the integrity of the plastic / color if done every third reheat or so.  Up until 280 to 305 on a reheat the plastic is sticky gooey, but still needs stirring ( rolling around in the cup ) to avoid hot spots.   Then, the plastic gets progressively thinner as the temperature approaches 340-350.   At 345 - 350 it is very thin and runny. Temps. above 350 - 360 will start scorching things.   Some colors and most glitters start degrading above 350 ( some at 340 on reheats ).  At 360 - 370 smoking gets rough very quickly and degradation is bad. Larger body baits will have a much higher tendency to dent while cooling ( contracting ) if you inject at 350 degrees.  Just hot enough to get full appendages without much injector force is optimum. The warmer your plastic, the longer you should hold the injector onto the mold; with light plunger pressure; to avoid dents.
 

[RTL]

This thread is Awesome!  Thank you guys. I injected 5 Frogs last night before I went to bed and man, they came out great!!!!!!!!!!

This morning I plan to pour a yellow belly, inject a Green Pumpkin Frog, add eyes and dip into clear plastic just to see what it turns out like!

hehe

[pjmcla]

You are now officially hooked.  Welcome to the addiction.

[kipbass]

Do I add colorant before I heat the Plastisol or after?

When working a new recipe I add after the plastic is hot and work in small 4oz batches. I always start with less colorant than what I think I need, then inject. If I don't like it I remelt and add more color. I'm writing down the drops on scratch paper and when I get what I want, I add it to my book. The next time around I add it to uncooked plastic so I get most of the stirring done then and create less bubbles.