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Managing Waste

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How do you manage waste? I have found when I am shooting if I don't remelt I seem to get about 80% waste. I can remelt about 3 times with no negative affects. On the 4th remelt I start to get color and smell change. Lots of heat stabilizer?

I seem to recall one larger bait maker here saying they never remelt. That they send all their sprues and plugs off to be recycled or however they dispose of it.

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That's the big negative with shooting. I use to throw all the sprues in a 2 cup Pyrex then top it off with virgin plastic. Even with that you will get some color change after a little while. You can take whatever you have left over and add a little green highlight powder and call it Nuclear Waste.

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i keep all of my sprues and reuse them as i am going thru the process of making baits except we use a 4 cup pyrex and then when we get close to the end i just save them in gallon ziploc bags for the emergency order and dont want to heat up a whole pot of plastic

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I pour from a Presto Pot and ususally cycle 5-6 multi-cavity molds per run. As I demold and cut off the spues I just throw them back into the pot. When I use up all the plastic in the pot I am left with a thin disc of plastic the size of the pot. I save it and when I make the next batch the same color I cut it up and throw it in with the fresh plastic. I have no waste at all.

Edited by Basseducer
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I pour from a Presto Pot and ususally cycle 5-6 multi-cavity molds per run. As I demold and cut off the spues I just throw them back into the pot. When I use up all the plastic in the pot I am left with a thin disc of plastic the size of the pot. I save it and when I make the next batch the same color I cut it up and throw it in with the fresh plastic. I have no waste at all.

And how do you avoid/reduce/eliminate color change and the changing smell of the plastic as you remelt.

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What Mark said. I'm throwing in 10 - 20 marble sized sprues at a time. They heat up and melt gradually so smoke and smell are not a problem. I experience very little or no color change with the pot. When I make a new batch (64 ounces) I cut up what was left in the pot and feed it in a few pieces at a time in each cycle. If I am continuing with the same color I simply add more raw plastic to whatever is left in the pot. When I do injecting I simply stop the mixer and draw plastic right from the pot then I start the mixer again.

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What Mark said. I'm throwing in 10 - 20 marble sized sprues at a time. They heat up and melt gradually so smoke and smell are not a problem. I experience very little or no color change with the pot. When I make a new batch (64 ounces) I cut up what was left in the pot and feed it in a few pieces at a time in each cycle. If I am continuing with the same color I simply add more raw plastic to whatever is left in the pot. When I do injecting I simply stop the mixer and draw plastic right from the pot then I start the mixer again.

I guess I'm just going to have to break down and use my little gear motor to setup a mixer. I was saving it for another project, but they are cheap enough (if its strong enough) that I can get another one.

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bob once you have your plastic up to temp it doesnt require very much torque just as its going through the gel stage. if your motor is weak on torque just stirr it by hand until its up to temp then use the motor to keep everything suspended???

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Bob, as a rule most large manufacturers only run around 20% regrinds(ground up sprues) to the ratio of the raw plastic. I personally don't use regrinds, I could on solid colors with no problem, but I find with laminates that I don't get consistent pressures therefore, I don't get consistent laminates, so I try to avoid using regrinds at all times. Just be patient and keep your eye out, there's something in development right now that can really help do away with the waste. The bad thing about selling this material for recycling, most companies want 20-25 drums to make the pickup economical. We've gotten really lucky, we found a somewhat local company that will take as little as 10 drums. On average a drum of scrap weighs around 350 lbs. So when they do recycle they want massive amounts. I know that they press the plasticizer out of the scrap and then I think the rest is sent to Indonesia for the manufacturing of tennis shoe soles. On average I go through a pair of tennis shoes every month and a half, stepping in the raw plastic and just the nature of the shop floor it reacts with tennis shoe bottoms bad. Within about a month, the toes of my shoes will start turning skyward, I probably spill more in a week than a lot of the guys doing hand pours use. When you handle 4 or 5, 5 gallon buckets a day, accidents are bound to happen.

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Bob,

I know you make your own molds, certainly not criticizing, and have no experience with cnc but do recall seeing some of your molds and thinking with the size runner you would have a lot of waste. Have you tinkered with the size sprue/runner leading to the mold to reduce waste?

I have. I am not very good at getting plastic without bubbles so it helps make up for it to some degree. I need to do some work on my plastic management techniques in stirring and injecting. My recent 5" grub mold uses a 1/4" sprue and does ok, but I get a larger number of dented baits. The long sprue with the bottom inject and top vent seems to help a great deal with the quality of the bait too. Its all a learning experience for me. The small stuff all comes out perfect with minimal effort, but the medium and big stuff I still need to work on my technique.

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When I knock the dust off my hand injector and shoot some baits I just throw the spurs back in as I am going. I don't really see the need to throw them out. To me that is throwing away money. You can buy runners and spurs from big company's. They sell them by the flat. Thats what they must mean by recycling them into money.

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