Casting Curious About Single-Doll Casting

The reason that most casting companies require a minimum number of dolls cast is that the mold making is one of the most expensive parts of the process. If you want just one doll it may end up being very expensive and it will also be rather wasteful as the caster would then have to destroy a perfectly fine mold. And it's not a matter of materials alone as mold making require a bit of skill, equipment and is not entirely without health hazards for the professionals either. If it were me I would hesitate to agree to making a mold knowing only a single doll were to be made from it.

If you only intend to experiment, is there a reason you need the doll to be cast? Would something like resin printing be an option? Or perhaps sculpting in a surdy material like epoxy and keep the original sculpt instead of casting?
There is also the option of less toxic plastics such as acrylic.

 

Well, silicone molds and polyurethane casting is expensive and hazardous, it doesn't make much sense to use prefessional casting methods for an sculpt that is not yet at that level.
Once you got an original you are happy with and believe in, you can look in to low minimum casting services again, but until then it seems like a bit of a waste. What is the saying? Putting the cart in front of the horse?

You don't need a widely popular product to breake even. Some casting services have minimums as low as ten. It's not like you need to sell hundreds of dolls for it to work out.

Besides, while I understand the desire to be able to share your dolls here even if you don't intend to sell them, it's worth knowing that casting quality is not the only requirements. Dolls have been rejected for things like unfinshed insides, badly fitting head caps and assymerty in the sculpt as well.

Edit to add: You can still discuss you home made doll in the Birgadoon (off topic) forum. And you can post your finished doll inte the "Completed Dollmaking Projects" forum to show it off. And the regular rules about off topic dolls being allowed in pictures with on topic dolls as long as it's the on topic doll that is in focus still applies as well.

 

Single doll casting works for a higher quality sometimes, but most of the time is just a "plus" for exclusivity.
Usually, dolls are made on molds like this:

Spoiler: MOLD

This kind of molds can be used a few times but leave marks and some parts with exes of resin as you can see on the right head.
This is not a problem, the doll will be sanded and polished eventually.
BUT! single doll casting allows you to make the doll using the minimum amount of silicone parts because the mold will be cut to take out the final figure, that means that you can have higher details in the part that in the "normal" process are sanded, Also single doll casting is a guarantee of a reduced amount of dolls with the same quality that could be good for limited editions with reduced production (one or 3 dolls). Also, a plus is that you can "guarantee" exclusivity to the client because the mold is destroyed when the doll is out.


But as lillith say, its a lot more expensive especially if you don't have experience making single doll casts, because it will take some tries to archive the quality that you need in order to make this technique worth.
you can practice with low-quality materials but If it's for personal use I don't recommend this method.

For example here in Mexico we use single mold casting for virgin maria expensive figures, and we put on the feet the information of the single cast to make it more expensive

 

That looks like a plaster mold for a porceline doll, though. This forum is focused on polyurethande dolls and thay are cast in silicone molds. Sometimes two part molds, but often single part molds are possible since the silicone is so flexible. They look quite different from the mold in your picture.
And no, they don't necceserily need the parting lines removed. Gates and vents, absolutely, but if the mold is fresh and you have a bit of luck and skill setting up, the parting line can be almost invisible. This is especcially true in single part molds as the tend to fit perfectly when new and freshly cut. And they often only have a single parting line, unlike a multi part mold.
If you are new to polyurethane casting and/or BJD in general it may be useful to know that this is why saturated colours are often cast first, when the mold is new, to reduce the need for sanding. Darker colours are a lot trickier to sand well without showing marks, compared to lighter colours. Is it not common to sand the entire surface of a polyurethane doll when it comes out of the mold. That would negate the point of the long finishing process that is done to prepare the original sculpt for mold making. Silicone molds are incredibly good at replicating the surface of the original, so rather than spending time sanding every single cast to perfection, this work is done on the original and that surface is what you will get in your finished parts (provided all goes well with the mold making).
The mold in the picture seems to be a four part mold. Molds that complex are usually only neccesary when casting in hard molds. And you can't cast plyurethane in plaster in any efficient way. (There are workarounds that might work, but why would you go through the trouble when there are better suited materials available?)

It's mid casting season here, so if you want any specific pictures of the molds ot the parts right out of the mold, let me know and I'll try to take some. I can't take pictures while doing the actual casting, for obvious reasons, but I can show you some of the set up and finishing work if you are interested. Let me know what you need.

 

@Lillith actually I had been working on casting different kinds of sculptures and colletionables for some time (even if I don't think that I have a high level on my casting because I have more experience with painting) but I'm new on casting figure actions and joints dolls (around 8 months with both), Usually I work with simpler molds, the reason why I showed that image is that is easy to understand and see the parts also because I don't have photos n.nU. anyway, all that you say is true and is very well explained!~ as a curiosity, that is why here in Mexico is obligatory by law to put the number of the cast and the number of sculptures that came from the same mold.

I had been looking at your posts and you had been here for a long time!! It's amazing to learn about different processes If you can share with me photos I will be more than grateful, pls share more about your final polish process.

 

I am only glad to be of help. I found a lot of valuable informationon on various doll forums that helped me when I first started out. No need to invent all the wheels and make all the mistakes when someone else has already done it for you.
I made a separate post about what happens after the cast is pulled out of the mold, as to not hijack this one.
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