Resin Casting

[commander alexander]

I would like to start resin casting, but I have no clue what products or proccesses to use. What do you recomend? I'm looking for processes, brands and types of materials to use for the molds and castes.

[Subtle Discord]

You're in luck. I'm really enjoying getting into resin casting recently, (have a look near the end of my WIP thread to see my first attempts) and I'm just about to do another entry about my on-going experience. I've learned so much so fast, and found that many tutorials and examples on-line tend to gloss over some (mostly little) things that I would have liked explained. I'm going to try to talk about the entire process including those said 'little things'.

 

I'll have a WIP thread entry done shortly, but it's going to be more about what I've made and some general information. I'm working on a much more in-depth article for my B&C blog that should be up in the next few days.

[Watcher in the Dark]

I am about to start doing some resin work myself. MicroMark has a nice little starter kit with everything you need to get started. There are also some Youtube videos out there of hobbyists showing some of the techniques that they use.

[Brother Sivak]

i used aeromarine products to make few figures.with help of some videos on youtube i was able to figure out how to make them.watcher thanz for the link on you put help.helped me find what i was looking for.

[ThisisJimmy]

Not quite sure what you plan on casting, but I've dabbled in the casting of shoulder pads. It truly was as simple as creating a rubber mould for the pads, from there I poured a 2 part clear resin into the moulds which took about an hour to set. The only thing I would say is that it is an imperfect method, as there was some air bubbles which was a bit of a pain. Also what I would like to say is that this may not be the most accessible of a method, as the components are fairly expensive and come in great quantities, and will go off if you don't use it in a timely fashion.

 

But good luck in your search, being able to cast your own bits can make life much, much easier, provided you know what you are doing.

[Subtle Discord]

Since it's going to be a few days before I get a full article together, I figured I'd give some 'cliff-notes' of what I'm using and doing. As with almost every topic, many equivalent products and differing techniques exist. Most are good/valid, but some are overkill or flat out wrong/dangerous. I'm just starting out myself, and urge any input as to products/techniques that I could add.

 

First; Google and read read read. There's tons of information out there, but you'll need to take the time to read it. Read and learn now, and avoid making mistakes that can waste materials or worse.

 

I'm using Smooth-On products (again, one brand of many) since I can get them at a shop just a few minutes away. As always, I try to support my local stores, especially if they are independently run, but many vendors exist all around the world.

 

I'll be honest and say Smooth-On also hooked me with marketing. Their sight is professional and they have lost of great Q&A, Tutorials, and Videos showing their product at work. You get a very good idea what you're going to get. I'm positive there are other products out there that will perform as well, or even better. I'll be experimenting to find better results and/or cheaper materials as I go.

 

For rubber (Called RTV - Room Temperature Vulcanizing) I've been using OOMOO 30. It's what you get in their 'starter kit', and works very well. A close cousin is their Mold Star 30 (Have some, but haven't tried it), which it is slightly thicker to pour, but makes a tougher mould. These products give you 30 minutes mix time, and take 6 hours to cure. Cure time usually comes with a trade off in mould strength. Faster curing RTV will make softer moulds that can tear easier, and may not last as long if the item is complex and/or detailed. How you pour the rubber is also important, so watch several tutorials.

 

For resin, I'm using their Smooth-Cast 300 product. Resin in general that is used for miniatures is very thin, and work well to run in to even the tiniest details. Fingerprints, tool marks, super-fine scratches, if you can see it, it can be replicated. (Read: Make sure your master prototype is perfect - flaws will show) How fast the resin will set varies widely. 300 Gives you 2-3 minutes 'pot time' that you can mix and pour the resin. Then I starts to 'kick' and set, which takes about 10+ minutes. A few resins are even faster, and many are slower taking 30+ minutes, or even hours to set. More time gives you more time to get bubbles out and/or pour several moulds at once.

 

With just a starter kit like this or others on the market, you can do simple stuff very easy, and even venture into doing very complex items. With well made moulds (Good venting, proper pouring gates, etc.) you can do amazing things. But, as has already been mentioned, bubbles are your biggest enemy. Using Talc to dust moulds as a release agent (opposed to spray on oil-based release) will help with bubbles. Vibration is also a good tool - pour the item, and use a vibrating table or device to shake it, dislodging bubbles. Also, 'pinching' the mould after it's poured can break stubborn bubbles free. The mould will spring pack perfectly. All that, combined with good vents, can get you very acceptable results.

 

I took it one step further to really get rid of bubbles, since they were being a real pain in the rivets on my work. (I do lots of rivets, so it was unacceptable to me) I place poured moulds in a pressure chamber before the resin 'kicks', and apply 50 PSI with a compressor. The pressure crushes the bubbles down, reducing their size (or even dissolving them completely) and once the resin is hard, the bubbles can't not re-expand. The difference a pressure chamber makes is huge, but it does add to the cost of getting everything setup.

 

If you just want to replicate things for your own army, keep things reasonable, and are willing to do some bubble-filling-cleanup, just a reasonably priced 'starter kit' will give you everything you need. A few things like a box of Vinyl Gloves, mixing sticks, some Talc, LEGO to build 'mould walls' with, a few sculpting tools, and some sulfer-free plasticine are all you need to add to the mix.

 

And a final couple of notes; Yes, these products have a shelf-life, and will last about a year from the date of manufacture. There should be a label/stamp/sticker on everything to give you an idea how old it is. However, there are products on the market that are aerosol can that you can add a little 'pocket' of gas that replaces the air in the bottle. These products will significantly increase shelf-life.

 

Finally; Copying someone's work and selling it for profit is, at best, really rude and slimy, and at worst, will get you into a lot of legal hot water. Do it for personal use only, or only replicate your own prototypes.

 

I hope this is a good start to give you an idea if your project/s are worth the time and money. As I said, have a look at my thread if you want to see what a complete novice at this can do. If you're willing to learn and invest a bit of time and money, the results will not disappoint.

 

Ok... I'll shut up now. :D

[commander alexander]

Wow, thank you for such an in depth reply Discord.