Mold making - My first mold

I decided to use a failed handmade fishing lure as my first mold subject, not because I wanted copies of it, but rather because I didn't care if it was ruined. I'd make the mold out of plaster, and make the copy by molding some hot glue into shape.

I realized I needed some way of suspending the lure in mid air to make the first half of the mold. Last week I made a failed attempt at my fist mold. I used a bed of leftover mashed potato. By pushing the lure into a bed of mashed potato, it should have been possible to make the top of the mold, then turn it over and make the bottom.

This mold is to be in two parts. I figured the approach would be to find the halfway point of the object, build a box around it, and make it sit in plaster to that halfway point. Then when it was dry, I could build up some new walls, and fill that with plaster. The mashed potato method worked, but the old bag of plaster I had didn't. It never set. I'm guessing it was because it had too much exposure to moisture over the last few years. This time I'm all out of mashed potato, so I'll have to suspend it in mid air.

My first step was to coat the lure in lip balm to prevent it sticking to the plaster.

Lacking any telekinetic powers to speak of, my new approach was to suspend the lure a centimeter or so off the ground in a vice.

Next, I made a box out of foil to hold the plaster, and slipped it under the lure.

I mixed up some plaster and water until it looked about right. (I'll work out what the ratios of plaster to water should be when I look into this a bit more)
And poured plaster into the box until the level reached halfway up the model.

After only about a half an hour it was hard enough that I could touch it without leaving a mark, but it still felt wet and cold, so I thought I'd better leave it until it felt totally dry. So leave it I will.

Now the waiting. I'm still not so good at the waiting.

I really need to get better at the waiting.

Continued - part 2

WARNING !!! Plaster can get very hot when setting 

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