Casting vertical molds

[NHProFF]

Can someone please explain how to cast vertical molds to create swirling patterns. I understand the process for casting a large block (1"x5"x5" for example) Measure resin, add color, add hardner, pour in mould, swirl. is the process the same for vertical molds? How do you "swirl" the colors since you only have a small opening at the top of the mold?

Also, I have seen a process where you do 1 color, wait for it to gel, add another color. Then pull the first color through the second. How is this accomplished with vertical molds? Is there a trick?

Thanks in advance.

 

[jason_r]

Just like with a horizontal mold. The library probably has a great article or three on this.

Prepare all your colors.
Pour all/part of 1 into the mold.
Pour in a 2nd.
Swirl with a stick or wire if you want (I usually don't, gravity does a good job by itself)
Pour in 3rd, or next part of 1st
Repeat until mold is full

So you're wondering why you'd use a different mold?
Because the effect is different. With a horizontal mold you tend to get swirls that either are throughout the blank and/or have a bias that's parallel to the axis of the pen. With vertical molds, the swirls are focused at the color boundries, and the bias is perpendicular to the axis of the pen.

So if you want: (crude ASCII-gram)
1121221212
2122121222 looking swirls, go with a horizontal mold.

If you want:

11
11
11
12
21
12
22
22
22 looking swirls, go with a vertical mold.

 

[snyiper]

Wow Jason that hurt my head to read...LOL

 

[EBorraga]

What if I want

12
32
13
21
13
21
12

In all seriousness I think you're on to something that I need to experiment with.

 

[Lenny]

36
24
36

=0)

 

[jason_r]

This old thread has a lot of useful info in it:
http://www.penturners.org/forum/showthread.php?t=69773

The reason I point at that thread is the OP mentioned waiting until 1 gelled. I interpret that to be the mayonaise stage or harder, and while you can get some color to pull through at that point it's pretty hard- and likely to incorporate air bubbles.

Other things to consider: (some of which I haven't tried yet)

- which color is denser? If you pour the denser color on top, it'll tend to sink through the other one- enhancing the swirling. If you pour it on bottom, it'll tend to separate, creating a more distinct boundary.

-how much do you move the cup while you pour?

-how high above the mold do you hold the cup? (higher = finer, deeper swirls)

-pour down the side of the mold to minimize swirling / mixing

-pour through a straw to create a focus of color

-use a wire with a loop on the end to enhance swirls after pouring.

 

[jason_r]

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ROFLMAO

 

[EBorraga]

36
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Only if she's 5'3 :biggrin:. Sir Mix Alot

 

[joefyffe]

Lenny: You are hallucinating!!! :biggrin::biggrin::biggrin::biggrin::biggrin: BUT in a healthy way!:tongue:

36
24
36

=0)

 

[NHProFF]

Thanks for all of the great info. Ill check out the library and see if there is a tutorial.

 

[DurocShark]

I alternate pours rather than swirl. The difference in "weight" between colors causes them to swirl a bit on their own, plus the weight of the pour itself. Gives a wonderful flame effect.

 

[PenMan1]

I alternate pours rather than swirl. The difference in "weight" between colors causes them to swirl a bit on their own, plus the weight of the pour itself. Gives a wonderful flame effect.

Yep! I am even less scientific. I alternate colors and if the pours include black or gold, they go in last as they always tend to sink to the bottom

 

[Bobalu]

I alternate pours rather than swirl. The difference in "weight" between colors causes them to swirl a bit on their own, plus the weight of the pour itself. Gives a wonderful flame effect.

Yep! I am even less scientific. I alternate colors and if the pours include black or gold, they go in last as they always tend to sink to the bottom

So Andy, are you suggesting I toss my handy-dandy patented MC Brooks swirling wire away and just pour, pour, pour? I've had some success with the "let it swirl on its own" process, but they still don't give me that "really swirly" look I'm after. More like two colors that swirl a bit where the layers meet, but not much between the layers. Like you, I'm using a heated Ultrasonic cleaner to thin the resin. The working time is short, so I usually pour the first layer about 90 seconds after catalyzing. If I wait much longer the PR gets too thick to pour. Could it be my timing?

Just one last question.... which color to pour first if you're just using black and gold? Maybe I'll try it both ways today and see which one sinks best.

 

[DurocShark]

Depends on how you got the black. If you're using PearlEx carbon black, it's about the same weight as gold (in my experience, using enough black to become opaque on a pen) so any method will work nicely.

If you're using dye for the black, you'll want to pour it first, then the gold. For me, Aztec Gold is pretty darn heavy and will head for the bottom if the resin is still thin.

 

[Bobalu]

Depends on how you got the black. If you're using PearlEx carbon black, it's about the same weight as gold (in my experience, using enough black to become opaque on a pen) so any method will work nicely.

If you're using dye for the black, you'll want to pour it first, then the gold. For me, Aztec Gold is pretty darn heavy and will head for the bottom if the resin is still thin.

I'm using Coastal Scents powders for my black and gold at this time. I just mixed up a few ounces of each to test it both ways. Unfortunately the black set up so fast after catalyzing that it wouldn't pour. That was the last of my Silmar 41, so I'll have to postpone this to another day. I sure am getting a lot of ugly bottle stopper blanks from all this learning process, but I knew it wasn't going to be easy.