Two questions about doll making ~~~ Balls and molds

I am a newbie with my doll making, but here is what I have learned by far ;
1; wooden balls are the easy way -but I had to shape my doll's kneejoints without balls, simply because I didn't find right shape&size balls when I was making that part. If possible, use wooden balls...
2; because I am beginner and just learning things as I go by, I think small details do show in the unbaked porcelain (like nails etc) -one just needs to make good plaster mold (I am still learning to do that ). Tiny details, like lines in palms and fingers and lips are made afterwords (either on the unbaked or soft baked pieces)
The key to get good pieces is in the making of good plaster molds -in my opinion . (At the moment I am waiting now one palster mold to dry, gonna open it in few minutes and I am scared already if I did it ok this time... )

And now some professional person should tell how things really go

Thank you caracal and Hasel ^^
It has become clear to me that making molds is an art by itself. Best idea seems to practice on how to make molds and sculpting at the same time, since the bond between them is so strong...!

p.s. Hasel, I believe you! A 6 part mold sounds like hell!

I have never used wooden balls in my work. If you use wooden balls it is hard to find ones that fit perfectly unless you build your doll around those wooden parts.

When you make a master you can include many details that will make an impression in the plaster (use pottery plaster) however, when you make a mold you have to be careful about undercuts which are areas on your original sculpture that will get trapped in the mold. It takes practice and trial and error to fully understand where an undercut will be. Sometimes you can deal with that area by making another part in the mold, like when molding a head, you might need to make a separate pieces for the ears. You can also add details later after taking the casting out and before firing it, nostrils are a good example of this. Here is a photo of how to deal with the ear. I ended up making a 5 part mold for this head:
017 by Tiny Shirt, on Flickr

No that part about stronger = less water it will absorb is not true.

I have used 3 kinds of different plaster now, personally the difference between them is so small I do not care for the special (more expensive) plaster used for porcelain moldmaking. The cheapest, bought in a big sack of 20 kg stuff was the best in my opinion, it sucks just as much as the special stuff and it holds detail just as well. I also found it less runny then the special kind. You also don't want a super-sucking mold because then it's harder to time it to make all your pieces the same thickness.

The trick about making great plaster is making a good mix with the water, I had a great teacher in artschool who chiseled this into my brain XD

First you take a cup (I use a cut in half rubber ball) and you fill it with water as much as you need, but not more then the half of the cup or it might overflow. Then you get your plaster, you 'snow' it into the water, this takes a lot of time but you need to make sure you don't drop any clumps in there so just powder it in. Try to make sure you don't do it only in the middle, but spread it over the cup. You contineu this until you start to see a survace. This is where you decide how strong your plaster will be, you can either stop or continue, I continue as I prefer the stronger plaster. You keep snowing until you get a thin survace that does not darken inmediatly, this you let sit for a minute or 2. Then you gently mix it with your hand (because then you can feel the thickness/warmth etc well) make sure to mix gently to not mix in any air. The longer the plaster sits the more stiff it will get, I usually let it sit till it has the consistancy of yoghurt and then I pour it in my mold.

Make sure to wipe your hands on a old towel or paper towels becaus when you wash them the plaster gets into your tubing system and thats not very good for it. Also, I use the rubber ball because when the plaster has set I can easily crumble it out because the ball is soft