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More accurate breast physics

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Avianman
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More accurate breast physics

Post by Avianman »

I am a mascot and puppet maker/designer. I often need to modify or create object that mimic movement and realism. I have something to say

The breasts on every doll I have seen, even the really pricy ones, have terrible movement.
Sure, they feel real enough, but they don’t move like real breasts do. For me anyway, the movement is a HUGE part of their beauty!

Even the gel and hollow breasts “bounce” but don’t.....what’s the best word....flow? They don’t flatten at all when the doll is on their back, and they don’t shift when on hands and knees.

I have read a few posts about this on the forum, and almost all concede in the idea that we don’t have the ability/technology, or that we can’t make them durable.

I say that simply isn’t true!

If you watch video on the silicone breast form vests/suits made for transgender people, you will see that the really good ones have breasts that are incredible in movement, feel, and weight.

Side note....there may be something here if you have a small breasted doll and want to change it up to a large breasted doll once and a while...just buy her one of these tops..they are pretty incredible!

Anyway, where was I ... oh yes... bewbs

I have been watching real boobs and fake boobs all my life. Felt many a boob as well. I have an idea that may improve the physics, weight, and feel.

But I need your boobs.

Ha! No, seriously....

If anyone has a damaged doll with a realistic boob size and wants to donate or sell the boobs for modification, hit me up.

In the meantime, I will look for boob only toys and forms. I have several forms now that, like the dolls, have a good feel, but the movement is terrible. Working on some mods and ideas now dealing primarily with weight and various fluids. I shall keep everyone posted!

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Maviarab
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Re: More accurate breast physics

Post by Maviarab »

One thing. Those are not very lifelike to touch, have a horrible outer covering and are primarily and main purpose for 'shape'.

They would be truly awful on a doll. But give it time please, everyone comes here moaning and complaining. The silicone world has been around a while now but was very rudimentary in it's inception. TPE has come along and pushed both to make advancements. Advancements are happening all the time, but in the reality of it, this industry is still really in it's infancy and growing and changing by the month.

Also, you have to remember, whatever is done, created, modded, whatever....it has to stand up to 'use'....and that in itself adds a whole level of complication to the project.

Avianman
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Re: More accurate breast physics

Post by Avianman »

Now hold on... innovation happens when people are willing to change what currently is.
A LOT of advancements have been made when someone else has an idea and wants to put it into action

Isn’t that what this particular board is for? Did I post on the wrong place?

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Maviarab
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Re: More accurate breast physics

Post by Maviarab »

No no you're quite right...just saying it's what we all want...just as you said..tech...not here yet. I'm sure someone can make wonderfully moving breasts...but would they stand up to use on a doll?

That's the nut to crack...combining it with durability.

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Re: More accurate breast physics

Post by Avianman »

Durability seems to be an issue with the dolls in general, based on some of the used doll sale posts.

Here is a question - what is the warranty on these? Anything at all?

I mean, we expect them to hold up to regular use when well taken care of. Like anything, certain options on a doll may be unwise to purchase if the doll is going to be used in certain ways...kind of like a "when used as directed" thing. An example is trying to make a non-standing doll stand up - it damages the doll quickly. It isn't a flaw, but rather, technically a misuse.

At least in the beginning, perhaps these might be something that isn't for everybody...of someone is into some rough stuff, they aren't going to want the doll with this motion as the breasts are inherently weaker. It will also probably mean storing the doll with some sort of breast support to prevent excessive "sagging" over time. Some different care will be needed, maybe even something to keep the TPE soft and strong. It may have a shorter life in general, but if we know that when purchasing, it might be ok. Like organic food - it isn't going to last as long as a twinkie...again, not a flaw, just different. The task isn't to get it to hold up identically to the current breasts (though that would be nice) but instead to hold up a reasonable amount.

There have been great strides in the last 15 years in these dolls, but often, we need a new set of eyes looking at them. There is often a case of "can't see the forest through the trees" We don't have the technology yet if indeed we use the technology that we are used to.

Durability is often stage two of a usable prototype.... and a super important one. I'll cross that bridge when I come to it... for now, I'M OUT TO BUILD A BETTER BREAST! :lol:

BuilderOfCastles
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Re: More accurate breast physics

Post by BuilderOfCastles »

Well.... but of course.

And most guys want bigger, firmer, perkier breasts... .that are still soft and squishy and jiggle.
Unfortunately, these are opposites in material characteristics.

The biggest problem with movement / jiggle is that it comes from weight.
Weight that has to be supported.

And this gets into materials that we really do not have.
Such as a skin replacement. There isn't anything in plastic that has the tear resistance at the thinness that skin does.

Would love to hear your ideas about creating a better boob.

And, you can get torso dolls much cheaper, if you want premade breasts to experiment with.

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Mcupplease
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Re: More accurate breast physics

Post by Mcupplease »

B-lite is a company making breast implants and the gel is unique weighing only 60% usual weight of gel. Maybe this technology can be coupled with doll building. The flattening and flow of the breast is greatly influenced by the thickness of the wall of the hollow breast. Much larger breast will flow and flatten better. The softness and elasticity of the shell material can contribute to movement and flattening. It's true what you say in the videos even the best jiggle does not really move properly and flattened. Also I don't like that breasts are molded in droop down configuration which looks good standing but lying down doesn't move up like a real breast should
Hi160ZZ (9,470cc) ...HI160BBB(8,450cc) ... JAR153BBB(4,400cc) ... AB110BBB(4.280cc) ... YL150O(4,020cc) ...
OR161K(3,800cc) ... JY140(3,460cc) ...
CP-Breastforms-KK(3,000cc) ... SM175L(2,900cc) ...
SH165R(2,850cc) ... JY150L(2,800cc) ...
SY167L-x2(2,600cc) ... SM150L(2,550cc) ... CLM-Torso(2,300cc) ... Ruby13 XXX BreastPillow(2,000cc)

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MikeOxbigg
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Re: More accurate breast physics

Post by MikeOxbigg »

They move just fine for a girl with implants. :D

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Nord
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Re: More accurate breast physics

Post by Nord »

Fill a small plastic bag with some thick type of liquid. That's very close to the feel we want to achieve. I am sure there are better rubber-type of materials to do this with, maybe a thicker type of what we have for condoms, for example.

Problem in the end however is how to implement this in a seamless way on a fully molded doll, with minimal risk of damage by wild sexing.

It would not be too much of a problem for a doll that is always wearing some form of bra, or bodysuit, to cover the seams. I wouldn't mind this, but it is certainly not everyones cup of tea.

I have actually considered to experiment with something like this for my WM140. I'm no fan of the D-cups and are regularly considering to attempt a breast-reduction to A or B, but haven't dared to do anything yet due to how hard it is to work with TPE.

One alternative I've been considering is to simply get rid of the tits completely, smooth out the surface with a heatgun, and have her wear a special sportsbra that can carry two separate fake tits in proper place. Those fake tits could be bags of liquid, and easily exchangeable to different materials like small pillows, or even different breast sizes depending on what I feel like.

You know what, maybe I'll just do a prototype this weekend, just for lols, and science of course :D
Aio - Sanhui 160cm AIO "Nonoka"
Rei - WM 140cm D-cup #39 & #53
Nymph - DH168 80cm "Shiori"
Ku - DS Ex Lite 163cm "Kayla"
Elva & Alva - 6Ye 65cm #M5 "Mina"

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MosMan
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Re: More accurate breast physics

Post by MosMan »

I am look at this too. Here are my thoughts of the moment.

Durability. If you are a manufacturer, you can't afford all of your product coming back. So if it is not durable, they can't sell it.
Understanding that, and playing with silicone, I would be happy for something that lasts more than a few months. If I have to replace it every 4 to 6 months, I would be willing to do it.
So I am working with that mind set. Not perfect. Not particularly durable. But I do want it to flow.

Breast implants. Since this is a medical device, good luck on finding any. Check your local laws before buying any. Part of the reason appears to be there are persons that like to do body modification. With just about anything. And in less than idea environments. I don't care, if that is what they want to do. However, no one wants to be sued over misuse of their device. And there are laws against playing doctor. I don't need that headache.

So far, a thin reinforced, fluid filled slicone shell has worked for me but not very durable. I am now looking at beads and/or air pressure. The idea is so what if it leaks. It is easy to pump it back up. I have looked at this off and on for over a year. I don't expect any break throughs.

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That Guy
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Re: More accurate breast physics

Post by That Guy »

Personally, I don't want the breasts to flatten and roll to the side, like real humans do, when they are laying on their backs. I like the falsie effect.

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Re: More accurate breast physics

Post by pup001 »

The most realistic ones i've seen are the ruby13 breast pillows.
https://www.youtube.com/watch?v=dUWq0NJb7lM
but, i think that company is defunct?
Also, they would have to be modular because you can't make a whole doll that soft.
Also, they probably damage fast, so they'd probably have to be replaced pretty often.

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Re: More accurate breast physics

Post by OnaGuy »

Magic Eyes I-cup Paizuri are pretty close in feel and movement to the real thing. The best I have felt in comparison to the real deal. They have have really awesome feel, when I sink my fingers into them. I believe they are of triple layer material. Or maybe 4 layer. I don’t remember. I have a pair myself. These tits cost about 100 bucks or so.

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MosMan
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Re: More accurate breast physics

Post by MosMan »

Just saw this post. I'll try slime as a filler too.
viewtopic.php?f=240&t=82826

I looked up a demo video for the Magic Eye boobs. Interesting. And I just saw a post in Buy Sell. . . No. I'm partial to silicone. But it is good to see them in action.

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Re: More accurate breast physics

Post by donoghu »

Been a while since I logged in on the forum.
Since I got quite a bit of money saved up, I'm looking up what's new in the LD world. (Date, my first and still current LD is still rocking it, but she does show a few signs of usage and I did made a few mistakes with her.)

I ended up with this topic which has been on my mind ever since Date arrived.

The 3 parts, with Date, that I have found lacking or maybe I should say made me feel strange are...

1) The hands' skeletons. (Date has a wire based hands' skeletons.)
I have wondered why joints-based skeleton are still so rare or expensive when it come to hands. It's like one of the most easily bulk-able kind of skeleton base props that could be made fast and efficiently with super low risk of rejects. (It could even be done with $10 worth of plastic/wire on a 3D printer). Not only is the joints-based hand much more durable, they feel 20x more real. I'm getting off topic, but well, this was the first thing that "hit" me with Date.

2) Lack of frame in the toes.
This might be only on the model I bought, but squishy boneless toes made me feel strange when handling Date. Especially when her toes was getting squished in the wrong angles. Hahaha. Obviously, the toes doesn't have the same importance of the hands and I would heavily avoid wire-based frame in that at all cost. Still, if joints-based hand skeleton was added to the hands, I would heavily consider articulated toes being added as well.

3) The way the breasts move and stay firm.
Now, I'm back at the topic at hand (or should I say "in hands"?). Obviously, Date is not the top-notch in terms of quality even as a TPE doll. After all, she's my first LD and I would have been crazy to invest more $$$ in something I lack experience with. Still, even with her semi-custom B-Cup size, I notice how her breast seems a bit "fake" as in "heavily silicon-filled breast-like" fake. (Ironic considering she's in TPE and not in silicon.)

It feels awesome on the touch or when pressed against. That's a given, but the amount of pressure required is what make them flat feel kinda off. For the breast to flatten the same way real breasts does (from my experience), I have to apply between 80lbs and 100lbs of pressure... and we're talking about a smaller size (B-Cup). I guess that hollow breasts might give a better result with less pressure, but I'm kinda scared by the idea of having a big empty space in there considering the risks that, usually, a bubble of air has on the durability.

I know that TPE has many possibilities and with a bit of engineering and thinking, I'm 100% certain it's possible to reach better results with not even any major changes to how TPE dolls are already made. The main issue that comes from it, from what I can guess (with all my knowledge from experiences and studies in many fields really close to it) is basically what I call the "fear of failure" that is responsible for a lot of stagnation in many industrial field. It's always like this. All knows it can be done, but nobody dare to do it first. When one does it successfully and it's a commercial success, the others magically start to also do it successfully within a matter of months or even weeks as they were all already preparing for it, but none would dare risk it publicly.

Here's an example of how it could be done with the current technologies of TPE available on the market :

Build the dolls with 2 layers instead of 1.

Usually, unless we're talking about a custom high-end doll, the dolls are made with simple pieces molded over a steel framed skeleton. You could say that it's like an Full Suit made of TPE that is put over the skeleton that looks like the body of the doll. It's simple to produce in chain and with the right injection methods during the molding, it's possible to have the "pieces" with different firmness and elasticity.

Doing it in 2 layers does add a bit of work, but it's relatively the same thing, but done twice.

You got a first layer that could be seen as a simplified layer of squishy yet really elastic soft TPE.
Once "cooked up", you keep the doll on the assembly/molding rig and apply a 2nd layer of more firm, yet still elastic layer.
Once "cooked up" again, the result will be a much more squishy/mushy doll with better physics for all the soft spot : breast, ass, arms/legs muscles, abdomen squishiness, etc.

As a matter of fact, this kind of process could be done many times and the result could easily beat even high-end dolls in terms of "feeling. quality if done right.

Here's why TPE dolls doesn't have great physics : They are made of TPE. That's right, but also wrong. They are made of TPE isn't the problem. The problem is that they are made of TPE in 1 go. Our body (be it a man or woman) is not made of 1 layer. We got bones, organs, muscles, fat, liquids, etc. under that skin.

TPE doll only have TPE and bones so the usual mistake is to interpret that it's "doesn't have organs, muscles, fat nor liquids."
I hope I won't get flagged for this, but here's a video on Youtube that display how "far" we can got with TPE or other plastique/oil based product to create something that feels real : https://youtu.be/5j2JBj3HJf0
(HUGE WARNING, that video is the dissection of a T-Rex. If you hate blood/organ being displayed and cut up, don't watch!)

Now, obviously, I'm not saying that we should see dolls with full set of organs, bones and pretty much all the stuff inside. (But I'm not saying either that it wouldn't be AWESOME.) I'm just saying that if we want something closer to the real thing, the first thing is to get closer to the real thing instead of trying to just emulate the real thing with a fake thing. (Ok, that might not have made sense, but it did in my head.)

Have a 1st layer with soft/squishy TPE that represents the "softness", then add a 2nd layer that is more firm over it. The thickness of each layer wouldn't be uniform, but more based on how much "softness" or "hardness" you want in the final result. So, around the breast area, You would have a relatively high volume of soft TPE from the 1st layer while, as another example, around certain part of the hands, shoulder (like Shoulder blades), groin, sides, parts of the elbows and knees, etc. you would have more of the 2nd layer which is harder/firmer.

Now, unless you want the doll to be purely cosmetic, I don't think that using hollow or "liquid filled" methods would be good. As I previously explained, Hollow means you purposely add a weakness spot in the material. Not only that, but it's kinda hard to do a quality check on something that is hidden within the doll once assembled, right? As for liquid, let's just say that science is not on your side because you would need it to be a "dry" liquid for it to avoid leaving traces of condensation whenever there's a relatively high diversity of temperature between the liquid and the surface surrounding it. (Not counting the issues if there's damages involved on whatever hold the liquid.)

By having 2 layer of TPE applied over the doll, we remove most of the risks involved with an hollow parts and there's no risks of seeing any liquid having any effect anywhere since there's no liquid, but just super smooth TPE (which is still "solid" in a sens.)

Now, it's not all "glory and success". I do also have a good idea of the risk of this solution.

1) There's 2 production phases.
Each production phase involve a risk of failure/scrap. Obviously, the risk of wasting resource is higher than with 1 layer. Still, the failure on the 1 layer isn't as important as the 2nd layer so there's a silver lining if the 1st layer has a bit of a defect. Not only that, but the 1st layer can be relatively fixed such as replacing a whole arm and having it "stitched up" with heating since any seams would be hidden under the 2nd layer.

2) There's a risk of "air" bubbles between the 2 layers.
I previously mentioned the bad side that comes with leaving some hollow space in the doll. The 2 layers does have the risk of finding air bubbles stuck between the 2 layers. This would, most likely, be the highest challenge involved with making the dolls with 1 layer vs 2 layers (or more). How do you remove air bubbles when molding something? You rotate and shake the "something" during before and, if possible, during the curing (hardening/cooking) phase. Either that or you use a TPE that has super slow curing so that you can leave it for 24h+ for the air bubble to slowly leave the TPE during the first 12h-14h when it's still "liquid".
Again, there's a silver lining as the fact that the "inner" layer would be the "softer" one, if there is any rupture/damage due to the air bubble it would be the softer/inner layer that would have "marks". The outer layer would mostly only be damaged by direct damage, dryness and overstretching unless the inner layer is REALLY damaged up to the point that it basically doesn't fill anything anymore.

3) The soft layer has to be soft, but still mold-able again.
This is the nightmare of many women during the 90's and early 00's when it came to having their breasts scanned for breast cancer. Soft breasts is hard to "controls" and bounce around easily. (Well, DUH! That's what we try to achieve!) My point toward breasts being scanned is because the process, from what I have been told, was well painful as the woman breast were "flatten" by the scanning device so that they doesn't move during the pictures and as to make sure it's "properly visible as a whole". When it come to molding soft/gelly breast, you would need them to be still at the right place as the 2nd layer is being added, right? The last thing you want is that the breasts has a thick lump of harder TPE on a side and a slim layer on the other because the breast lumped on a side while the 2nd layer was applied.

This is a bit like the air-bubble risk explained above. To counter this issue, the doll would have to be molded in a special way when it comes to the part that are sensible to movements during the curing. The breast, for example, would have to be cured while the doll's body would be facing forward, but also slightly downward (like 45 degrees). This way, the mass and mold can work together with the help of miss gravity.

This is one of the thing that requires some adjustment from how dolls are currently being assembled/made. Currently, they are made "straight up". They are hold up by a pole through the vagina (screwed to the pelvis' steel skeleton) which is screwed off when the doll is ready. Making the doll at 45 degrees (or maybe a bit less) is a challenge and might require a bit of tinkering around the articulations of the abdomen, pelvis and shoulders so that they don't move during the curing of the 2nd phase.

An actual solution does exist, but like any additional step, it comes at a risk. They could have some sort of pin-based locking mecanism in the joint.
(The joint being locked up physically by a small pin made of steel that "lock-down" the joint.)
When the curing of the 2nd layer is done, the pin are removed and the tiny small hole left by them are filled up and heated/removed/fixed.

Wow... I never though I would write all this just as to how "more real physic for dolls' breast is possible"
But, hey, that's one possible way of doing it.

=EDIT=

Yeah, I'm not done yet! I though about another possibility.

If anyone (or any company making dolls) feel like they truly have a good understanding of how to adjust the components in the TPE, something that might be more efficient when many the TPE dolls with 2 layers could actually be to do it in reverse.

Make the doll with the skeleton in "pieces" like it's currently done, but design the molds for it so that the interior of the doll is highly hollowed. Not fully hollowed such as having some edges or "inner-beam" that can be glued to the skeleton. once the doll outer layer is done, fill up the hollowed parts with the liquid state TPE which, once cured, will be super soft/mushy.
For it to be applied correctly, it would requires a quite a bit of observation and the right tools. When an hollow part is being filled up, it would require a needle-sized air extractor (like a super tiny straw) so that the air can leave the empty space of the hollow part as it's getting filled with the soft/smushy TPE. Once filled up, a bit of heating would remove any trace of the "holes" involved in the filling and the extraction of the air from the hollow part.

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