Skeleton Realism.

[Vipenis]

What about carbon fiber? It would be expensive but light weight and temperature resistant.

[rubherkitty]

The weight of a doll is the silicone or TPE. Carbon fiber, titanium, etc has all been tossed around, but the weight savings vs cost is not there for a doll. Dragsters and space ships, yes. Ok, maybe a $125K sexbot!!

[BuilderOfCastles]

What about carbon fiber? It would be expensive but light weight and temperature resistant.

Again, it isn't as weight saving, or as strong as you think.
Nor is just a little bit more money. "expensive" It is MUCH more expensive.

You are going from cutting a piece of standard pipe (with anything, hack saw, cutoff saw...)
To a thing that require an autoclave, pressure vessel, actual mask (respirator), someone who knows what they are doing.

And the weight savings aren't really there.
You are comparing a thin walled metal tube. Actually very light for its strength and durability.
And comparing it to a thicker walled plastic/carbon fiber mesh thingy.

You might shave off ounces, but not pounds.

(and we didn't even get into joints, and how they have to be metal, and how do you attach metal to the carbon fiber...)

So, the reason you would use carbon fiber is to create something that is human bone shaped.
Something you can easily do with carbon fiber (you already have to make a mold, no one said it had to be straight).

Like the shoulder ball joint and upper arm bone. That can be made in carbon fiber (if you had a reason that that would make for a better doll)

Areas that i think of using such is in making a pelvic bone.
However, i feel that many other plastics would be better and easier

And the one area that carbon fiber really excels, its cool looks, don't matter because (hopefully) you will never see it.

[nicvncnt]

Areas that i think of using such is in making a pelvic bone.
However, i feel that many other plastics would be better and easier

Abyss tried out a GRP (fibreglass) pelvis a few years ago but it didn't work out too well - I think it was just too fragile. The thing with bone is that it's really, really strong, stronger than steel in fact, so while it would be great to replicate the feel of a real skeleton inside the doll, only a very strong material would be up to the job.

[rubherkitty]

After reviewing this thread again, I don't think it was mentioned, but one reason dolls don't use human type skeletons in the bones would be too close to the skin surface. Anywhere the bone is within 1/4" of the surface you have a chance for the skin to tear. That's why they use tubing in the core of the doll body.

[Satisdix]

skeleton frames are light. Removed hers to do repairs, and realized all the weight was the silicon, and a hassle to carry boneless. She's 65 lbs complete, 55 lbs boneless.

[BuilderOfCastles]

Areas that i think of using such is in making a pelvic bone.
However, i feel that many other plastics would be better and easier

Abyss tried out a GRP (fibreglass) pelvis a few years ago but it didn't work out too well - I think it was just too fragile. The thing with bone is that it's really, really strong, stronger than steel in fact, so while it would be great to replicate the feel of a real skeleton inside the doll, only a very strong material would be up to the job.

Yep, most of my ideas for a pelvic bone only match on the outside to reality. Inside its all supports and webbing

and definitely not in two pieces like an actual pelvic bones.

And further, the connection to the back bone is the hardest part. Both because you want the hips to be able to rotate for sexual position, but also you are having a connection across the weakest axis.

Lastly you want this "pelvic bone" to take up lots of space, to reduce the amount of silicone and thus weight.

My ideas are to use a flexible and durable plastic such as Delrin or HDPE... and thus, it may have no actual use in the skeleton staying together. But we will see.

[coozykai]

Have doll engineers looked at the use of carbon fiber and aluminium? it would give a slight amount like healthy bone in a human. the connective material is also an issue to be studied and investigated.

[GYOWWAD]

skeleton frames are light. Removed hers to do repairs, and realized all the weight was the silicon, and a hassle to carry boneless. She's 65 lbs complete, 55 lbs boneless.

In that case, would it benefit to use as large diameter of pipe as possible (say, for legs on "thick" dolls") to remove weight? I suppose there must be some minimum thickness of TPE/silicon for softness/structural integrity but more volume being taken up by empty "bones" makes sense to me.

[BuilderOfCastles]

Have doll engineers looked at the use of carbon fiber and aluminium? it would give a slight amount like healthy bone in a human. the connective material is also an issue to be studied and investigated.

No, Chinese doll engineers are working with bent steel yokes welded to the ends of pipes and the resistance to bending is done by torquing a bolt. The advanced skeletons use plastic washers. (its just outside of the dark ages)

Haven't seen a one of them even use castellated hex nuts, or anything advanced.

However, the skeletons are "good enough" and its a quantum leap to the next better skeleton.

We will not get any great weight savings by using exotic materials in the existing designs, so why spend 100x more for little gain?

Where things get interesting is using new types of joints
and much different structure in the stomach / back bone area. Where you have lots of space to fill, and more flexibility is needed for sexual positions.