The Hunt For Big Fish with Larry Dahlberg

Mike (or Larry if your checking from Costa Rica),

I have a question. When I pour plastic lures with Alumisol (plastisol), I notice that they will "weep" what appears to be oils afterwards. It's not enough that they feel greasy, but if I place them onto a piece of paper over night, I can see the liquid soak into the paper. Sometimes it carries some of the color from the dye with it. I'm using a softener with the plastic, and I'm thoroughly mixing the softener in prior to heating the product to start the cure. Does it have to do with the softener, or is this just the physics of the product? If I bought a super soft plastisol from a manufacturer, would it basically be just a normal plastisol with softener added to it, or is it a different "recipe"? Would I just be robbing Peter to pay Paul? Just curious.

Thanks gentlemen,
Scott

You might be adding a little too much softener, but, in general, all plastisols are made the same. Standard weight plastisols have softener added to make it softer. All super soft plastisols will "weep" a little.

Now, don't get me wrong, not all plastisols are equal. Some settle out in storage, some are less clear, some smell more, some ...... quality is variable from supplier to supplier. I find that Mike makes the best for my uses.

How much softener are you adding?

You know what..... I'm not really measuring. I'm adding maybe 15% (tops) by volume. I wouldn't think that would be too much, but I'm certainly not an expert in this area. Thanks for the feed-back.

Give it a quick stir after heating when the plastic is clear and in it's "thinned state" before pouring. You may get some air bubbles but you can let them rise first and let it set for about 2 minutes then give it a quick 30 second blast to get it back up to temp. Should eliminate that issue. Usually (as angler said) it's an issue with too much softener or sometimes not properly mixing the heat stabilizer in (if you're using that)

Ok, now you've opened up a new can of worms. Heat Stabilizer.... How, what, when, where, and why do you use it? Please be detailed, as it's use can make or break the outcome of the final product.

Thanks.

First things first. I mentioned that some products settle out in storage. Alumisol is pretty resistant, but it can settle if left or stored for a long time. When it settles, the part that helps the plastic cure, the plasticizer, will settle. If you don't mix the container completely, then the cured and poured plastic never properly cures. This might look like leaking or weeping. Take your plastisol and shake it very well. On some of the brands I used years ago I would take a metal coat hanger, cut a piece off and bend an elbow, then put it in a drill and used it to mix the plastic. If that was or is the issue, you can fix it pretty fast by simply mixing raw material better before pouring it out of the bottle.

Now, heat stabilizer is a different issue. I don't even know the limits to how much to use, but it does not take much. In fact, for most pours, it is not necessary at all. If you want to re-meld plastic several times, then it can stop or reduce the yellowing of the plastic. If you want the clearest, most colorless pour, the it is useful to add a half dozen drops into about 250 ml of raw plastic. If you are getting a little smoke when heating, a few drops will reduce it, but better yet, heat is slower.

I have one sift plastic I pour where I want a clear and colorless plastic, loaded with silver glitter. A few drops of heat stabilizer helps keep it clear and colorless. But..... most brands of heat stabilizer are actually yellow themselves, so add too much and you cause the yellowing you are trying to prevent.

Hope this helps, let us know how the progress is going.

My plastisol hasn't settled. I shake the CRAP out of before use- every time. I should probably invest in some heat stabilizer anyways. I have had my product yellow on me before. I heat it very slowly and methodically though. I have a microwave in my "man cave" that I put on low when heating the product. I check on it periodically during the heating process to ensure I'm not over-heating it. I have a laser infrared thermometer I use (a NICE one, not Harbor Freight) to check the temp. I always stop when it hits 350 degrees. I have found that the best way to pour plastics is in numbers. When you make a mold of a lure you like, make multiple master out of casting resin. Then make another mold with 4 or 5 cavities in it. Then you can use all of the plastisol you heat up in one swoop. If you learn your quantities well, you can get pretty precise with the required amount, and minimize left over plastic. But when heated to the proper temperature just one time, I NEVER have the plastisol yellow on me.

Thanks for all the feedback guys. I tuck it away in my mental repertoire. It's only a matter of time before I need to tap into it again.

Scott

hi guys, Larry here;
I've been pouring and melting soft plastic since the early seventies and in my experience, some "weeping" goes with the territory. It is the nature of the beast. Remember all the problems with melted tackle boxes when plastics were first introduced? They changed the plastic formula the boxes were made out of, not the lures! Quite simply, the more plasticizer (softener) in the ratio, the more weeping you will get.
It can be mitigated by using Alumidust to bolster your colors when necessary rather than using more dye. My advice for bleeders is to simply use less dye.
But, like a fresh baked raised doughnut or biscuit, which will leave a wet spot on a piece of wax paper when fresh but dry out when left in the open a few days, items made of plastisol will also "dry out" a bit in time.
Personally, I don't see the problem as long as stuff isn't bleeding all over the place. Infact, I put mine in a zip lock back then add a shot of corn oil or olive oil to keep them slick and shiney.
Heat stabilizer will not solve the "bleeding" or "weeping".
best,
L