Casting with Blue Stuff and Two-Part Epoxy

Not a lot of updates, but that doesn't mean I haven't kept busy. I am definitely a recovering bits addict, during my previous stint in the hobby I would buy whole Space Marine Tactical Squad kits just for the two or so studded shoulder pads. This was before the current prevalence of bits stores. That was like 2006, since then I have married, had a few children and moved 2000+ miles away. This time around I am having to be more conservative with my spending. That said, I am still a bits fanatic. So I started experimenting with casting my own spare parts. I watched a lot of videos, read several articles and started here. 

I ordered some reusable thermoplastic named Blue Stuff from Green Stuff World and a two-part epoxy resin named EpoPutty by Alteco. 

First step is to start a pot of boiling water and then remove your Blue Stuff from the package. While the water is boiling you can cut your blue bars into smaller blocks, but it isn't necessary. Once your water is boiling pour it into a heat safe bowl or mug. Next put your Blue Stuff into the water. 

After about one minute it becomes malleable and you are able to bend it into itself.

Now you are able to tear away chunks of Blue Stuff and make the first part of a two-part mold. Do your best to have half of the bit pressed into the Blue Stuff. I also recommend making guide holes to line up with the other half of your mold. I started with a Genestealer Neophyte Hybrid Power Pick and Head, a Cadian Command Plasma Gun and a Forge World Elysian Sniper Rifle.

It takes about three minutes for the Blue Stuff to become completely firm, but it begins to firm immediately so try to work quickly to capture small details. After the bottom mold is firm remove some more Blue Stuff from your hot water and firmly press it on top of your first mold and bits. 

After about three minutes it will be completely firm and you will be able to split the two halves. You will have to apply some pressure but be careful to rip or tear your mold. When completely firm the Blue Stuff feels like rubber.

Now that your molds are finished, open each of your two-part epoxies, tear off roughly equal parts of your resin (here it is the blue tube) and hardener (silver tube) and knead them together like you are playing with Play-Doh or Silly Putty.

Once you have an elastic putty that is solidly one color, begin to firmly press it into one half of your mold, followed by the other half. Then line up the guide holes firmly press the two half of the molds together. It is recommended to wait three hours for curing in open air and six and half hours curing when submerged in water (this is the go-to epoxy for making imitation reef for aquariums). In my opinion the resin becomes almost unworkable after about thirty minutes, so try to have everything set quickly. When time is up separate your molds.

I waited somewhere in between three and four hours. As you can see in the picture there was quite a bit of flash and that is caused by excess resin in the mold. 

After removing from the mold, clean away flash, remove mold lines and check for loss of detail. 

As you can tell from the picture there is loss of detail, mold lines, mold slip lines and areas where resin didn't get into the mold. In addition to using an excess amount of resin on the outer edges of the mold which caused the flash, I also used too much resin where the molds join and it made the bits almost one and half times thicker than they should have been. Also I lost a lot of detail when trying to clean the model with a hobby knife because some areas of the casts were not completely cured. At this point I was a combination of excited, disappointed and pleased. I waited over night and cleaned the casts some more and ended breaking some pieces.

Some take-aways from the first session, use less resin in each mold, be mindful of how to get the most out of the small details and know ahead of time where you want mold lines to be. After a few days of pondering it and rewatching a couple videos I decided to make a second attempt. 

Here is a comparison to the original plastic bits.

Here is a comparison to the original casts. (New casts are on the top)

Last is a comparison of all three. (Left is the original plastic bit, the middle is the second cast and the right is the original cast)

I was able to reduce the thickness issue, more effectively minimize mold line impact and capture more detail while avoiding detail loss. While it was considerably better it is still about 65% of where I want to be with a personal recast.

What will I do differently next cast? I will play with the surface area ratios per mold half and really focus on trying to capture any detail where the two halves meet. I will make an even more focused attempt to use less resin in the mold. I will let the casts cure for a minimum of five hours before clearing flash and mold lines, but since I work so late at night it will like be 16+ hours before I can initially clean them.

From all the research I did, EpoPutty seems to cure the hardest and has the best durability, but it can be prone to losing detail. I am in the process of tracking down some old Warhammer Fantasy Battle bits that have large smooth surfaces and not a lot of fine detail, and I think that is where EpoPutty will excel. On the flipside the consensus appears to be that Milliput Supre Fine White two-part epoxy is the best two-part resin for capturing intricate details. I am not ready to give up on casting yet, so I will get some Milliput Super Fine White and test it out. It might just be correct to have both on hand for different projects.

Quick shoutouts! 
Green Stuff World for Blue Stuff and Milliput purchases
crankmeisterj for EpoPutty (they are very knowledgeable and willing to help, great communication!)
Plasmo for a great video tutorial on the process I described

What's next? I need to get back into paint mode and try to finish a squad for Necromunda/Kill Team in about a month and half. Should be easy right? Well considering I haven't done that once in 33 years, condensing that down to a month and half puts some pressure on me. I also have four fluff blog posts in draft stages that I work on as I get inspired and be on the look out for plans/goals for 2019 in the near future ...