Soft Plastic Bait Mold - Curltail

What is this?

This is a mold for a soft plastic fishing lure, intended for small batches to recycle other damaged swimbaits. There are two versions, “thin” (black pictured, and shown in the video) and “reinforced” (green pictured), thin has better action, but the reinforced bait has a more durable tail.

What do I need?

Besides this mold, all you need is

• a source of plastisol, (cut up damaged soft plastic swimbaits in this case, not all worms are plastisol so be careful mixing them)
• a microwave
• a high temperature container such as a pyrex measuring cup, 
• a large enough syringe (plastic works fine as long as you dont get it too hot)
• optionally additional dye or other additives
• (recommended) a well ventilated area
• 2 G clamps (3d printed is perfect here) or 2 squeeze clamps
• a worksurface (a silpat makes for easy cleanup of any spills, or a smooth clean counter)
  
  

How do I use this?

If you have all the requirements, first you would cut up your damaged baits and add them to the measuring cup adding any extra colors you want. (I found sharpie is a good way to add a dark purple color, just color the pieces a bit before melting, other color markers probably work)

Then you will want to line up the mold and clamp the two halves together, in a way that the large hole is upright and can have some pressure applied to it without moving. (the mold clamps better and lasts longer without any indexing in my experience)

Once your plastisol bait mix is cut and optionally colored, put the measuring cup in the microwave (in a well ventilated area. It does smell, but not permanently if you manage the temperature properly, so be careful, and or use a dedicated microwave). In 15-30 second increments microwave the plastic until it starts to soften, mix with a chopstick/stirring spoon, and continuing to microwave slowly until it runs smooth (if it is heavily smoking or browning it is too hot! Think a thin sauce consistency.)

once your plastisol it hot, and your mold is ready for pouring, purge the air from your syringe, (you may want to tilt the cup beforehand to make sucking up enough plastic easier) and get at least 5-10ml, the more the better but trying to avoid sucking up any excess air. Then QUICKLY, put the nozzle of the syringe up to the larger hole on your mold. It can be worth marking the side of the syringe if the nozzle is offset to make this easier, you need a moderate seal to get a good injection.

Now, press down on the plunger moderately quickly, while keeping some pressure on the mold. Not so much you separate the halves and warp it, but enough to keep a seal. Press until you see either plastic coming from the smaller hole, or feel the pressure change and have plastic coming back out the main. If you prepared multiple molds you can easily fill more than one at a time if you have enough plastisol as long as it is still hot enough. Once it turns "chunky" it needs to be reheated. let your mold cool between uses and before separating, to have it last longer. PLA WILL warp overtime, but I have gotten a least a dozen uses out of one mold, as it wears you will have a small amount of flashing to pick off around the edges of the bait.

Printing Recommendations

I used pla (black) and pla+ (green), I have seen people recommend abs as well. The higher the temp and softening point the longer the mold should last.

Use at least 3 walls, 30-40% infill minimum, there needs to be enough thermal mass that it doesnt warp, its not just about strength.

Using adaptive layer heights in the slicer works well here, I just set it to maximum quality in orca to help get better quality and better accuracy on the tail and tail spout.

All of the baits and molds you see are printed at 50% of the original size, I think 50-30% is a good size for most jigheads.

I personally think the “thin” model is better, especially since it is so easy to re pour damaged baits that losing some of the tail isnt a big deal. I prefer the better action.