Clay For 2-Part Silicone Molds

[one-off baits]

I've searched for a few days on here and haven't found a good answer yet. I've learned though that it must be sulfur free. What kind of clays do you guys use? I figure it must be somewhat soft to be able to push the soft plastic master down in it?

[Vodkaman]

You have to carve a hollow to fit the masters, you cannot simply push them in. Even if you could, the displaced clay will just bulge up and spoil the line. You can find clay tools in most hobby shops and very cheap.

 

I have always used kids modelling clay. It is very soft and easy to work with. But it may transfer color to the mold, but this does not matter to me. Most members use a clay called Skulpy.

 

Dave

[JRammit]

I used the sculpy original and its an absolute pain!.. Good for modeling, too hard for making a bed

Even tried play-do, easy to work with but does not like moisture.. When it gets wet it sticks to everything!

The most important thing is sealing around the master.. If any mold material leaks into the cavity, your mold is ruined!...... I think what you need is synthetic clay, but I found the easiest route is for me is plaster

Pour a thin layer of plaster, push the master halfway down and let dry (makes perfect seal)... Pour silicone over... You don't want to pull your master out of the silicone, so break the plaster into pieces to remove... There will be some clean up required before pouring the second half, but the same goes for clay

[one-off baits]

The plaster sounds like a great idea

[JRammit]

Keep in mind, for soft plastic baits you can make the whole mold from plaster... Same process, and much cheaper!

I only use silicone for hard bait molds, or making soft pieces as masters for soft baits (pieces that would be impossible to remove from a plaster mold)

[Cami]

Here we all use plasticine, it is easy and it does not react with RTV 2 components silicone. The grey paste is plasticine.

Bye.

 

Cami

[Travis]

Same here Cami.    

 

For soft plastics however I directly mold into the plaster of paris (actually I use Durham's Rock Hard Putty as I think it gives a better mold). 

 

Search the forums and you will find a lot of information on the subject.   .  One can add all sorts of steps, if that is your nature, but I can tell you it is not needed (vacuum, vibrating tables, additives, heating in oven, and countless other things some do).   Just takes some practice to get the consistency and work on your technique

 

Not as much information on two part RTV but many of us have and do make them.

[JRammit]

Same here Cami.

For soft plastics however I directly mold into the plaster of paris (actually I use Durham's Rock Hard Putty as I think it gives a better mold).

Search the forums and you will find a lot of information on the subject. . One can add all sorts of steps, if that is your nature, but I can tell you it is not needed (vacuum, vibrating tables, additives, heating in oven, and countless other things some do). Just takes some practice to get the consistency and work on your technique

Not as much information on two part RTV but many of us have and do make them.

X2 on the Durhams.. I refer to it as plaster cause its pretty similar, but easier to work with imo

[goldenshinner]

anyone care to share pictures of the steps with the various plasters and alternative mold making materials along with pictures. also do these alternative mold materials tend to shrink much, or flash. any tricks to getting good molds. like can you deck sand them after they are done, just to "clean" up the mold?