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Bubbles?

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If I had to take a guess I would say it’s micro bubbles in the plastisol.  If you really don’t wanna spend the money on a degassing. Chamber the best way is to let it sit in the microwave for a couple of minutes after it’s been heated up . You may have to heat it up again. It’s the best way I found to do it.

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3 hours ago, wallyc14 said:

If I had to take a guess I would say it’s micro bubbles in the plastisol.  If you really don’t wanna spend the money on a degassing. Chamber the best way is to let it sit in the microwave for a couple of minutes after it’s been heated up . You may have to heat it up again. It’s the best way I found to do it.

Agreed!

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In my experience, the marks are caused by pouring hot plastic in a cold mold. If it were bubbles you would have bubbles throughout the bait, not on the surface. 

Try warming your mold up and see what happens. You may have to vary your plastic temp too as well as vary how fast you're filling the mold. 

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If you are pouring out of a Pyrex or something like that into a two piece aluminum mold of that body design I think you will always have bubbles with or without a degasser. Those ribs in that stick bait will naturally trap air in a hand pour situation. I imagine some of them are being released and and becoming entrapped in the body as well as making the surface pock marks. Warming the mold, pouring hotter, and pouring slowly may help and reduce these bubbles. But in my opinion if you only hand pour and not hand inject that mold you will always have issues with air entrapment.

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By the photos those are cold cracks caused by not heating the mold first and you didn't hit the center of the gate when you first start pouring.  Try heating the mold and pour until you get the pour stream and center consistent, once you have those down you can go with a cold mold.  It's all about repetition

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On 9/30/2019 at 4:30 AM, McLuvin175 said:

If you are pouring out of a Pyrex or something like that into a two piece aluminum mold of that body design I think you will always have bubbles with or without a degasser. Those ribs in that stick bait will naturally trap air in a hand pour situation. I imagine some of them are being released and and becoming entrapped in the body as well as making the surface pock marks. Warming the mold, pouring hotter, and pouring slowly may help and reduce these bubbles. But in my opinion if you only hand pour and not hand inject that mold you will always have issues with air entrapment.

I had the same thing happen on a worm mold from BTS. The mold had horizontal and diagonal ribs. The diagonal ribs came out just fine as the air would rise and escape to the next rib and so on. The horizontal ribs would always trap air. Slowly pouring a very hot stream down the center of the hole helped a lot, but did not eliminate the problem. Hand injection molds are set up with the cavities horizontal with the ribs vertical eliminating the problem.

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What appears to be bubbles is actually the contraction of the plastic when you drip or miss center.  By design the "rings" are cut to prevent capturing bubbles, I've poured thousands and can honestly say I've never had an air bubble in a ring.  One thing though if you fill too fast you may see some air trapped at the top just below the reservoir.  It should take in a 5" about 5-6 seconds to fill the cavity, fill backup and top off the previous pour (eliminates dents).  As I posted previously practice hitting the center and you'll see this go away with repetition.  A tip for success is to get in the habit of always holding your pyrex at the same height and always start with a narrow stream.

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