Pop Mold Tutorial Part I

[longhorn]

POP Mold Tutorial Part I

This is a tutorial for making a one-piece multi-cavity Plaster of Paris (POP) mold for making soft plastic baits. I wrote the instructions as carefully as I could but you'll have to have some experience to get a feel for some of the steps in this process. After a few molds it'll become easy.

Materials needed:

Plaster of Paris (available at craft stores) I think the craft POP results in a smoother mold.

Elmer's Glue All

Mixing bowl

Large spoon

Empty 20 oz soft drink bottle

Water

Dishwashing detergent

Serving tray or other flat surfaced item (which will be the base for the mold)

Scotch brand permanent double-sided tape (office supply stores)

Masking tape

Plastic container the size of the mold you wish to make. There are lots of ways to make a mold box…this is just one of them…I like the way these smooth containers release from the POP.

Knife

Original soft plastic baits in numbers sufficient to make the number of cavities wanted

(the originals will end up a with a bunch of tape goo on them and are usually thrown away…I guess you could clean them with something if you really need to save them)

Clean the surface of the tray to ensure the tape will stick.

Cut the bottom out of the plastic container (to allow the plaster to be poured through). There are many ways to make a mold box, I'm showing one that works for me.

Place container on tray upside down and trace the outline of the inside of it

Apply permanent double-sided tape to entire area with no overlap

Wash plastic originals in detergent to remove any oils and dry completely. This is to ensure they'll stick to the tape.

Place plastic originals on taped surface inside the mold outline area. Press firmly down with your finger all along each bait to ensure they're stuck down good.

Place container back on tray in alignment with traced outline. Then use masking tape to secure the container to the tray and to prevent leaking.

Mix plaster in the bowl, using cold water, to the consistency of pancake batter.,,too thick will not work well. The most common error is not making the POP thin enough. Add water only a little at a time especially when it’s close to being ready…it goes a long way. Make sure you mix enough POP…the volume will shrink when you mix it with water. If the mold is too thin it will not be durable and will have more of a chance to break when you're removing it from the tray. So don't just cover the lures…add enough to make a durable mold.

Pour the POP into the container

Pick up the tray and rock it gently so the POP moves it back and forth to ensure coverage and to release air bubbles that are trapped next to originals….you will see them rise to the surface. The POP should be thin enough to flow back and forth. You can also gently tap the bottom of the tray.

Make sure tray is on a level surface and wait until the plaster sets up.

Another way to make a quick and easy mold is to pour the POP into a container and simply push the masters down into it.

The only trick here is to make sure the bait is down far enough into the POP to ensure full thickness and you need to stand by for a few minutes and keep pushing the bait back down until it stops floating up in the POP.

The plaster will become warm as it cures. After the warming occurs and has cooled it’s time to start separating the mold from the tray. A common mistake is to try to work on the mold too soon and could result in a broken mold.

First carefully work the container back and forth and remove it from the new mold.

Next separate the new mold from the tape and tray by applying pressure with a knife a little at a time on all sides. This is a critical step. The mold will be stuck down to the tape so carefully go all around and loosen until the mold is free. Too much pressure in one area could result in a broken mold. Don't stick the knife under too far to avoid damage to a cavity.

Not a bad result..a few small bubbles.

Now go to Part II of this tutorial