Skeleton Realism.

[Pentiki]

I'd also like to see a more realistic skeleton. I think the arguments about plastic are somewhat spot on, but for realism, you don't need a whole fully posable skeleton.

If a few specific processes were replicated semi realistically in fiberglass, i think it would do wonders. Fiberglass should be able to stand up to tpe casting temps, with the right resin, and is strong enough to be durable. This would allow all the fake "bones" to be attached to and cast in with the rest of the posing skeleton.

Having just got my first doll recently i was most disappointed about the lack of:
Convincing mandible and maxilla. They don't need to move, just be feelable. A sinus canal would add realism, improve cleanability, and solve the face bulging problem.

Collar bones and ribs, and shoulders . The chest wall looks good, but it's unrealistically soft, similarly the shoulders are squishy until you dig in. Some emulation of scapula would be nice also. Similarly, a more solid thoracic region of the back would add to immersion.

Pubis and hip blades. Like the ribs, only somewhat worse. The lack of convincing resistance from these parts is unfortunate. This is where you would "hold on", normally. Sit bones would be nice, for immersion.

Lastly, analogs for elbows, knees, heels, ankles. These are places everyone is hard, but dolls (at least mine) are weirdly soft in these places.

In terms of design, i can understand that making these sections thin to create a hard skeletal process feel more realistic will reduce doll longevity if nothing else is done. But, it seems like using a high durometer mix in these areas to improve durability in addition to some fiberglass plates under the surface to enhance immersion could be a workable solution.

My general reaction to initial contact with my doll was that its external appearance was that of a skinny person but it felt to the hand like someone with quite a bit more cushion on them. Dolls need more bones.

[Justforfun2]

Actually, real bones in most women standing 5 feet to 5'1" weighing in around 100 pounds, her bones wound weigh about 15 pounds. Now, if it were made out of good strong plastic, to replicate bones, it would weigh in about and pending the plastic used, from 5 to 7 pounds.

The metal skeleton in these dolls, I have no idea how much they weigh, so I must guess they probably add up to about 20 or 25 percent of the dolls weight. Just a guess, so if the dolls weighs in at 100 pounds, then metal skeleton might weigh 20 to 25 pounds, of course this might be from a taller doll, standing about 5'8" to equal the total weight of a living women of 5'1". So technically a doll is lighter than an actual women.

The thing is, to use good unbreakable plastic, and to make mold/s using real human bones at first, would cost more than using metal. Even after the first casting, and molding the cost would be high, for the materials, and assembly time, alone. Meaning to modify a plastic skeleton to work similar to a ball jointed doll, would add a cost of $1,000 or more.

Simply said, to give doll bones it is possible however, it will come at a price most of us cannot afford.

The problem with realistic skeletons is that they are very heavy. In addition to that they are not well suited for sex. They are good for posing for pictures. Fixed springy skeletons are better for sex, but they keep the doll in the same resting position of course.

[Average Joe]

I'm curious to learn how silicon dolls are cast though, as I would think that would be at high temperature as well.

Silicone cure time is accelerated with heat. I assume they pour at room temp and use some type of device to vibrate out the air bubbles. Then they may apply heat to reduce demold time.
Ps. Typical demold time of platinum silicone is 4 to 12 hours, the shorter times also have shorter working times. I'd assume with $1,000 of silicone that one would want the longer working time

[dreimal2001]

My general reaction to initial contact with my doll was that its external appearance was that of a skinny person but it felt to the hand like someone with quite a bit more cushion on them. Dolls need more bones.

I agree 100% - I would even pay more for sucha doll … very skinny and with real Feeling of bones...

[TMT1310]

The weight wouldnt be such a problem if they could move them selfs. Like robots or smth.
Or instead of steal they could use duralumin or carbon fibers.

[Robert01]

When we design our dolls we have always had the objective of making the skeleton as noninvasive as possible. I'm wondering if there are guys who are turned on by feeling the bones inside a doll's body? Might seen like a weird question but in my line of work I've heard it all

[dreimal2001]

very small, bony chest.. with Feeling of the bones.. this would be a Dream of me... on the whole sexdoll market have Nothing lile this.. … so sad...

[jwhf]

interesting

[BuilderOfCastles]

Now, this is a fascinating subject.

However, we quickly run into a case of an experienced materials specialist saying, nah, doesn't work.

There was a thread on this forum about making better doll finger wires.
They used a 3D printed hand piece, and it broken during first testing.
Then they used an eye-bolt embedded into a 3D print, and got... further.

The stresses on joints are far more than any injection molded plastic can take. Including delrin and

So, what you have to look at is things like metal ends with carbon-fiber bulges in between.
What this means...
By increasing the diameter of the pipe, you make it stronger to most bending forces, for the same amount of material.
Therefore, the carbon fiber areas bulge out from the small metal ends.
You can see this kind of thing in high end bike frames.

- - - - - - - -

A doll skeleton can be made lighter, but at great cost. Further, most of the weight is in the joints. Where you have a couple bolts, blocks and yokes. And these really can't be made lighter.

Unless you figure out a different joint type. Most of the joint stress is to keep doll positioning. You tighten up the bolts so that the friction keeps the doll from falling into a puddle.

Now, the other aspect was for more real feel.
This can be done with fiberglass or carbon-fiber inserts. (these do not melt)
However, not only do these add extra complexity in assembly and what can go wrong in casting,

BUT!, they also make the doll not as real. The dolls feel as good as they feel because they have elasticity throughout the structure. If you decrease the thickness of the TPE, you also decrease the squishiness.

You know, when you hug a woman, it is that all her internal organs and joints squish. If her skeleton was as solid as a metal skeleton in a doll, there would be no squishiness. It would be less than that found on a pair of rubber handle covered pliers.

- - - - - - - -

A really important question i would like to ask all of you is

What is the lightest a doll could be before it stops feeling good to hold?

A blow up vinyl doll you can snuggle with, because it just moves away from you, for it has no weight. But there is definitely a gap between that and a 100 lbs of dead weight just laying their motionless.

[dreimal2001]

the weight is not important for me... just the Feeling to feel a very small bony chest

[MrGojira-12]

When we design our dolls we have always had the objective of making the skeleton as noninvasive as possible. I'm wondering if there are guys who are turned on by feeling the bones inside a doll's body? Might seen like a weird question but in my line of work I've heard it all

I wouldn't necessarily call it getting turned on by the feeling of the bones. When you're trying to hold your doll by the hips while being intimate and those hips/waist are not really there, that feeling, that grip is missing. It feels off.

[DarksBlade]

Now, the other aspect was for more real feel.
This can be done with fiberglass or carbon-fiber inserts. (these do not melt)
However, not only do these add extra complexity in assembly and what can go wrong in casting,

BUT!, they also make the doll not as real. The dolls feel as good as they feel because they have elasticity throughout the structure. If you decrease the thickness of the TPE, you also decrease the squishiness.

You know, when you hug a woman, it is that all her internal organs and joints squish. If her skeleton was as solid as a metal skeleton in a doll, there would be no squishiness. It would be less than that found on a pair of rubber handle covered pliers.

I always picture a carbon fiber or graphite composite similar to high end tennis rackets used for an overlay on the ribs collar and pelvis. as for the fingers i cant understand why it is so hard to improve the technology for it has exsisted since the Victorian era. And i dont know about the rest of you but i have known some "boney chicks" so that plier handle comment is not far off for fingers or pelvic blades


despite what you might think that is a prosthetic hand from the 1800s


or Hollywood's terminator if you need more modern


but this for the carbon fiber i mention just thinner and used internally.

[SN162A085T]

All very good suggestions. I can confirm 100% the frame is not the issue. I've torn the skin 100% clean off of 165 centimeter doll and the frame itself weigh less than 10 lb. The tpe is the problem. There is no need to go plastic they use ultra thin tubing for the frame. If they just used tubing closer to the diameter of the actual legs arms and torso taking the skin thickness down to under an inch, this would create a hollow cavity in the middle freeing up tons of weight in tpe. Closed cell foam is also a great idea. Except that the implementation would be quite costly so I don't think the factories would even consider it.

[Thirsha42]

I don't know, thought mold lines were cleared with cautious scalpel work. Even then the lines are still visible. Is it actually possible to fuse TPE or silicone so tightly that the seam is nearly invisible? Would the seam hold, or would it be a logical break point once stress is applied to the area?

Any two part mold is going to have a parting line. If you used a metal mold it is possible to make the parting line very small but even the Lego group, which has engineered their molds to be within .04 mm variation, still has parting lines. The only way to not have them is to use a single piece mold but those get destroyed in the demolding process and so are not economical.

[SeanSteel]

I just wanted to put my 2 cents in. I think that if you want it to look it's best, go all out with the skeleton. I've tried using less realistic pelvises for years only to be disappointed. I must have 10 makeshifty pelvis all made from various loops of metal and plywood, even hobbling together some pvc tubes of varying sizes. Finally I gave up and used gods design. I've still got a ways to go of course.