Sep 252014

Over the past several weeks, I’ve been working on a RG Z’Gok as well as a GMII that would eventually be put together into a simple diorama. The exact plan wasn’t laid out as I didn’t want to spoil the surprise, and I honestly did not know if this “plan” would even be successful. But, I took pictures of the whole process and it sorta turned out how I figured it would. There are some issues that I learned, and should have learned when I first tried this with the Sazabi’s shield. But I am definitely much more confident in this process, so the next time, yes, there will invariably be a next time; this should be much more successful.

Starting off even before the RG Z’Gok was released and before I had snapped together the GMII, I used a stand in GM and a wood base that I had made for the G3 almost 10 years ago. The basic idea is to create a scene with the Z’Gok swimming over a long dead GMII, on it’s way to fight in that one epic battle from Gundam Unicorn. Where all these old Zeon suits spring out of the woodwork. That’s the basic premise. So, on goes the GM stand-in, laying down on the wood base. I then built an acrylic box measured out to the dimensions of the wood base using a hot glue gun to attach the 4 sides. The box is then test fitted over the base with the stand-in GM. Height is checked against my pressure pot to make sure it fits. And my plan is somewhat solid, time to execute.

First step I did was to quickly mold some rocks using lightweight hydrocal. The stuff is found at any railroad or even hobby shop. Mix according to the instructions with water and pour into rubber molds that I also picked up from the local hobby shop. I used playdough to create sections in one of the rock molds so that I can have smaller pieces of rocks. The stuff takes about 2 hours to cure enough that I can remove them from the molds, but takes another full 24 hours to fully cure. The rocks are sanded down and cut and placed on the base with the acrylic box around to test the fit. Satisfied with the fit, the rocks are glued to the surface of the wood base.

With the rocks set, I go and get to work on the GM. It’s quickly snapped and sanded and test fitted onto the surface of the rocks. After the test fit, I cut a few parts off the poor GM, it’s left arm and right leg to make the suit fit into the idea that it’s sunken and left for a number of years under water. Again, the acrylic box is used to make sure it all fits within the confines of the base borders.

At this point, the base and acrylic box are set aside and I get to work on building the GM. Cutting it to add some battle damage with a hobby knife and some styrene glue. Painting the sucker up after I get the battle damages done. I did not want to go overboard with the battle damage. So just a few bullet hits on the skirt and upper chest. Then some styrene roughed up some select areas.

With the GM painted, a clear gloss to protect the paint, decals added, another clear gloss to protect the decals, the panel lines and paint chipping in the same step, and another clear gloss to protect the panel lines and paint chipping. A filter is applied. A clear flat is sprayed to protect the filter while giving the surface the necessary grip for pastel application.

At this point, the RG Z’Gok has arrived and I’ve snapped and sanded the over engineered 144. Since this has been covered in previous posts, no need to repeat that information here. Moving back to the rocks. I had several test pieces from my original molding, so I can test some different colors out. The painting process for the rocks is just like a wash technique. Over thinned pigments applied to the surface. FOr this process, I picked up some cheap acrylic paints from the local crafts store. Thinned with water and applied with a brush, the rocks start to look more natural.

Here is a half hour video on how the rocks were made from start to finish as well as bits on finishing up the base.

Some woodland scenics are glued to the surface of the GM and the GM is permenatly glued to the rock base. Notice that there is blue tape around the base. Since the base was previously finished, I want to protect the finish of the wood as much as possible, so blue painters tape is applied to the edges.

Again, the Z’Gok is getting work; painting and slight weathering, just a small filter.

The important thing here is that both the Z’Gok and GMII have been sitting for at least a full week if not longer to allow the final clear coats and paints to cure. In my last attempt at encasing a painted plastic part in clear resin, the resin reacted with the paint. I had not clear coated the part. Lessons learned. CLEAR COAT TO PROTECT. Then allow it plenty of time to fully cure up before moving on to the clear resin.

With the two suit sitting curing up. I return to the acrylic box and spray the insides of the box with mold release. Resin is an adhesive, it sticks nicely to things. So, with part of my planning, I figured that mold release sprayed on the clear acrylic sides will help when I need to remove the sides. The acrylic box is attached to the base with the hot glue gun. Note, the glue gun needs to make a solid water tight seal around the base as I don’t want the liquid resin leaking out.

With the acrylic box in place. The first layer of clear resin is poured. I’m using an epoxy clear resin that has a very long cure time. When resin cures, it heats up, and I did not want to risk a melted mess of plastic that I’ve seen from other folks that have attempted even a partial clear resin over plastic build. The exact materials I used is from Silpak, their E108WC with H-403 hardner. A 40% hardener to resin mixture. The cure time is 48 hours, but depending on the mixture ratio, you can speed this up or slow this down slightly. Speeding this up will generate more heat.

The first layer, I poured too much too fast, and didn’t take the time to pop bubbles. I just poured and threw the whole base and box into the pressure pot figuring that the pressure pot would take care of all the bubbles for me. It did not. So I ended up with the surface riddled with bubbles. The good thing here is that it’s not fully cured, so I can take a knife or a dental tool to poke at the bubbles opening them up.

First layer of clear resin, bubble hell

I poured the second layer before the first layer fully cured and using a knife and dental tool, started popping bubbles and forcing the resin into the bubbles. For the most part, this was working. I got rid of a decent number of surface bubbles. But the mistake was already in place. I should not have immediately thrown the thing into the pressure pot. I should have left it out for an hour or two while I still had the pot life and popped bubbles here and there as they surfaced. I should have also poured a thinner layer, so that a thinner layer has an easier time to fill in the holes resulting in less bubbles. Patience is still VERY important in model building.

The third layer was easier as most of the GM was already covered. Very few air bubbles formed at this step. And once this layer hardened enough, I placed the Z’Gok into position and using a wire, held the Z’Gok in position while I poured in the third layer. I did a thinner third layer and that seemed to help with a slow fill, reducing bubbles.

Another fun thing that happened at this layer of clear resin was the discovery that I didn’t completely seal the sides of the acrylic sheets. So I was getting a slow pool of clear resin. The whole base was tilted to one side while I quickly plugged in my hot glue gun. Wiping away the excess and applying a huge layer of hot glue to patch the hole. I let it sit for a few minutes to check that the patch worked, then put the entire assembly into the pressure pot.

The fourth pour was rushed. I wasn’t really paying attention, and over mixed the resin. This caused the resin to cure MUCH faster and resulted in bubbles. And the different cure rate also resulted in a more clear distinction between the previously poured layers. More lessons learned. I was getting pretty complacent with the success of the previous layers and just got careless.

The air bubbles from the 4th layer required a final 5th layer of resin. This helped fill the bubbles from the 4th layer. And this took a full 48 hours to slowly cure.

Last night, the resin felt hard enough, so I took a hobby knife and started cutting and pulling away the glue. Stripping away the glue, I pulled at one of the acrylic sheets and with a little bit of force, the thing popped away very nicely. Success! Well, now I get to see all the missed air bubbles from the various pours.

The rest of the acrylic sheets are popped off and I’m left with a roughly 10 lb clear resin paper weight.

I still need to let the block air out a little and in a few days, I can get to polishing the thing and finishing it all up.

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