Prevent color blending in resin

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jeporter02

jeporter02

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Does anyone have tips or a resource for how to minimise color blending with resin pours? I would like to be able to swirl different colored resins together without them over-blending into a mottled mess. I've poured a second color into another resin and not swirled, but the pattern is less exciting. I could wait until the resin starts to thicken, but then I worry at that point I'll have lost the window to effectively pressurise and eliminate air bubbles. What do people do to improve the swirling without blending the colors together? Thanks!
 
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John Underhill is the expert in this realm, but I can tell you what he told me - measure the temperature of the resin, and do not begin mixing the colors until you are at about 90 degrees or higher. I have seen many recommendations to start at 95F up to 115F, Yes the resin is getting thicker at that point, so you have to be efficient at your pouring and mixing, and getting the mold into the pressure pot. Mixing different colors at lower temperatures allows the resins to blend (i.e. Blue + red = purple), but at the higher temperatures, Blue + Red = Blue & Red Swirl.
 
Here is a link to a video by Jake Thompson that covers this topic well. This is for Alumilite Clear Slow but he also has a video for using epoxy resin. The temperature for colour separation for epoxy is about 120 degrees to 130 degrees.
 
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jeporter02 said:
Does anyone have tips or a resource for how to minimise color blending with resin pours? I would like to be able to swirl different colored resins together without them over-blending into a mottled mess. I've poured a second color into another resin and not swirled, but the pattern is less exciting. I could wait until the resin starts to thicken, but then I worry at that point I'll have lost the window to effectively pressurise and eliminate air bubbles. What do people do to improve the swirling without blending the colors together? Thanks!
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A large part of this will depend on what type of resin you are using. Without knowing which kind you are using, it is hard to give you an accurate method. I have poured PR, Urethane and Epoxy Resin. All have different characteristics.
From your post, it sounds like you may be using Alumilite Clear Slow (or Clear) which gives you about a 12 minute working time. For Alumilite Clear Slow, I use an heat measuring gun and I start pouring at 105 degrees for up to 3 color pours. For anything over 3 colors, I normally start pouring at 95-100 to give me a bit more time.
 
@jeporter02 The time for setting is a guideline. Setup, with Alumilite Clear Slow, is more a function of the temperature. (I use a laser thermometer)
There has been some really good discussions on the Podcast "As The Pen Turns" (I listen to it on Apple Podcasts). Jonathon Brooks has talked about the critical times for mixing, depending on the effect you want. Somewhere between 80-95F. How long it takes, to get to this temperature, can be greatly affected by the ambient temperature of the room, by the starting temperature of the resin, even by the micas and additives that you put in. Just because you hit 12 minutes, does not mean it is going to suddenly harden.
My shop temperature is a little lower than average, I keep it at 65F in the winter time. I found that even at 18min, my resin was still not up to 100F, so I would mix it in fear of it suddenly setting. While my pour still worked, I did not get the large swirls I was looking for, and the colours blended more than I wanted. It also took forever to cure. Even after a week, there was too much flex in my rods. It took a couple of weeks for them to fully harden. Now, after Jonathon's recomendation, I raise the shop temperature to about 71F when I am getting ready to pour. I also put my resin out on the table, under my heater blower, while I set up. My last couple of pours have resulted in better swirl patterns, the resin temp is about 85F at 13-14min (and rising quickly lol).

I am definitely a learner when it comes to the intricacies of casting Alumilite. While I've been dabbling for years, I have only recently started more focused casting.
Good luck.
 
Thank you all. Video was great. Not sure why that didn't come up when I did a search on Youtube for this, but appreciate the link. Sounds like I need a temperature gun. Good thing I've got a birthday coming up!
 
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