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Frank

Bubbles Is Fresh Plastic.

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I know some people have had issues with bubbles in fresh plastic. For dark colors this is not really a problem. Awhile back I was pouring for a customer that is real fussy about color. So I made up four quarts one in each cup. While I was injecting I had the uncooked one resting on a griddle that was set at about 250. So it pretty much preheated the plastic. It takes me awhile to shoot these baits so they were setting on there for awhile. When I cooked them no bubbles. Seems to me the heat made the air trapped in the resins let go. So on the next one I took the temp of the preheated plastic and it was about 210. Same thing no bubbles.

The other method is to put the plastic in a vacumn chamber and remove the air that way. I now have a four gallon vessel to remove air. This way works much faster that the preheat way but both seem to work great. This way I can really mix my plastic good and remove air just before I use it. I know there are plastic out there that don't have a bubble issue but they have a premium price tag. Some now are selling plastic that has been vacumned but they cost more. And if you aggressively mix it you could put it back in then you paid extra for nothing.

Purchasing a personal vacumn unit may sound expensive but in the long run it will save a lot of time and frustration. A simple cooking pot and a clear lid with a gauge and some valves to regulate what is going on. I say clear lid so you could see what is going on in side. The plastic grows at least two times it's volumn so you have to watch.

The griddle way is much cheaper but takes much more time. This process takes more time as the plastic really has to be there for awhile to let the air release.

Either way you at home can choose a way that works for you. And now that you know the bubble issues can be controlled by you and not who you buy it from. Mix your plastic as much as you feel it needs and be assured there will be no more bubbles.

I know of at least one guy that does it after it is heated but with it growing so much I will stick to doing if before. Hope this takes some of the mystery out of the bubbles in plastic. Frank

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We have been told in the colder climates, even as gentle as you think you are being, its still getting air when stirred. I have seen some get air just sitting.. I said before, anyone in this business doing a bunch of work should get them a degasser. we recently purchased 5, 5 gallon pots. And some of the plastic still hits the lid because it is growing so much. I have been degassing every since it cooled off. 

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That pretty much my point people could control there own end result. Now that they know how and that it's not hard. But how can you control how someone mixes a product when it is in there hands. I have one mixer that makes a froth in plastic. But I have a choice so I don't use it. Others might not and make a problem worst. I also transfer all plastic into a container that has a flat easy to reach bottom so I know it's mixed well. No jugs with corners that make it hard to mix.

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I agree, the end user really is the only one in control... In a presto its really not a issue... As much as in a micro wave.. The air is like a balloon, just keeps getting bigger and bigger. You can almost not see it with the naked eye till its heated.. I have some videos of the process I will post, Unless you are doing one up..

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So what are you removing when you degas?  

 

Trapped air bubbles one thing but more interested in what volatile organics you are removing.  I have asked some manufactures before but haven't  always received responses from... well no one with a chemistry or science background.  Depending on the hygroscopicity of components water may be drawn into the "plastic".    I am not clear on how close or important specs are in the product suppliers are making.  From most of my inquiries and experience figure it isn't a huge issue and variability from lot to lot is considerable.  

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Well I am not a scientist so can't answer the voc question but I am sure if it was harmfully to you it would be on a msds sheet. But the one I have read had no great concerns. Not being a chemist all I can say is the finished product is clear and free of anything that would cloud clear plastic. It's really amazing when you watch how much air that some of the plastic has. But I know one thing when I get a fresh drum of plastic in and stir it once there is a lot less air then when I stir it the next time. It get more and more as I stir it again and again.

Not going to make a video of plastic being vacuumed to me it's kinda like a video of paint drying.

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Well I am not a scientist so can't answer the voc question but I am sure if it was harmfully to you it would be on a msds sheet. But the one I have read had no great concerns. Not being a chemist all I can say is the finished product is clear and free of anything that would cloud clear plastic. It's really amazing when you watch how much air that some of the plastic has. But I know one thing when I get a fresh drum of plastic in and stir it once there is a lot less air then when I stir it the next time. It get more and more as I stir it again and again.

Not going to make a video of plastic being vacuumed to me it's kinda like a video of paint drying.

Some people have no clue what your talking about or how it works, Plenty of people know how paint dry's... :)

 

Your not removing nothing degassing that isnt being removed when heated.

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Some people have no clue what your talking about or how it works, Plenty of people know how paint dry's... :)

 

Your not removing nothing degassing that isnt being removed when heated.

Good point but it's still not for me. I am sure there is plenty of videos with a vacumn chamber on you tube.
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It's fun to hear you guys who deal with this stuff commercially talking shop.

I home pour, mix the snot of my microwaved plastic with a bent wire coat hanger to try and keep the salt and flake in suspension, and never really worry about bubbles.  I leave the mixer in my NorPor cups while I'm pouring and mix again after a couple of cavities, so I can keep the plastic well mixed, if I'm pouring a lot of plastic at one time.

I see bubbles coming up into my sprues on my hand poured Ika bodies, but I never really worried about air bubbles in my thinner injected baits.  Maybe injecting them helps to get rid of bubbles, or maybe I just don't notice them.  

I always figured any small trapped air bubbles would make my baits float more, which isn't bad.

Whether they do that or not, I haven't notice any real loss of strength, or transparency, on my own hand pours.

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At first the bubbles did not matter. But lately bait that I make are transparent and small. So bubbles could be seen easily. Even with most swim baits I make it did not matter because with a pearl belly you and darker backs the bubble were not visible. Now it's up to me on how I want it.

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At first the bubbles did not matter. But lately bait that I make are transparent and small. So bubbles could be seen easily. Even with most swim baits I make it did not matter because with a pearl belly you and darker backs the bubble were not visible. Now it's up to me on how I want it.

 

I can see how bubbles would be a problem if you're selling baits.  You seem to have it figured out.  Good for you, and thanks for sharing your method and insight.

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I can see how bubbles would be a problem if you're selling baits.  You seem to have it figured out.  Good for you, and thanks for sharing your method and insight.

It was more of a problem because I was trying to match baits. The others he had were pretty much bubble free. Not that I figured it out it was Don from Spikeit that educated me on the vacumn part. The preheat was a fluke that happened. Don told me the difference between there injectasol and there pourasol is the pourasol is deaired. The extra cost is from the process he uses. But also told me it could be done at home without a lot of trouble. He was right and I always have bubble free plastic any time I want.

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Its awesome when you have people that will educate you. I had to learn on my own. At the same time I helped a guy who thought he had a whole barrel lost. He is now de airing his after heat. They wanted him to ship it back to them. At a huge cost. He paid less for his system than shipping one way back to LW...

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