Apologies for not updating sooner, but the weather's been sketchy, so my pirate internet connection on the boat wasn't working and I haven't had time to stop and log on anywhere else. Enough of that, here's what I've been up to for a couple of days...
First, I finished building up the base around the back and chest pieces:
That done, I built a clay wall to keep the silicone from running all over the place once I started brushing it on:
I did this with both pieces:
The little pink and purple pegs spaced around the edge are there to form holes in the rubber. Later, when I build the mother mold, they will be removed to form keys in the holes. This will all become clear as progress continues.
With both parts ready to mold, it was time to mix some rubber:
This is a pretty physical task with a full bucket of silicone, but it gets easier every time.
The first batches were mixed with a purple catalyst that makes the uncured rubber pourable. Once it's mixed, I brush it on to pick up all of the surface details:
Here's what the back looked like with about four pounds of rubber laid on:
All of the pink parts are where the high points of the prototype are almost poking through. These parts are paper thin at this point and will need reinforcement if I want the mold to survive the removal of the prototype. More on that in a moment.
Here I am brushing rubber into some of the chest details:
Once the plurple silicone had cured, the next step was to mix a few batches with the thixotropic (pink) catalyst. This catalyst makes a much more viscous uncured rubber that will cling to a vertical surface while it cures. This way I can build up a lot of thickness without having the rubber dribble away from the high points:
After a solid day of frosting my armor with noxious chemicals, it was time to knock off before I started getting goofy:
The problem with the thixotropic catalyst is that you end up with little ridges and spikes all over the outside of the mold. When you build the mothermold these are likely to lock the rubber into the rigid mothermold in ways you don't want, so the next step is another coat of pourable plurple rubber. I did this this morning:
The back has lots of unique shapes that will keep the rubber jacket mold properly aligned in the mother mold. There aren't as many to the chest, so in order to keep the rubber jacket mold from moving around in the mother mold I added these little bumps to the chest:
Right now I'm on a lunch break while I wait for the rubber to cure. Hopefully I'll have the mothermold done today sometime.
Meanwhile, I've finalized the shoulder boxes:
Here's a shot of the rear details (because I'm proud of them):
And I've also finished the lower back detail insert:
I've used up about half of the rubber I've budgeted for this mold, so I think I'm just about right on track. Stay tuned...