lockable loose joints

pitspoes · Post by **pitspoes** » Sat Jun 08, 2019 8:24 am

Reading the forum about losening joints, wanting loose for sex and stiff for posing.

Has it been tryed to lets stay the knee to make a joint that locks and unlock by pressing the side?

you would have the advantage of a loose & fixed joint.

abbadon31 · Post by **abbadon31** » Thu Jun 27, 2019 1:50 pm

Like a press in to unlock and release to lock like the head of a speedlite

abbadon31 · Post by **abbadon31** » Thu Jun 27, 2019 2:17 pm

press to unlock and release to engage teeth

Thirsha42 · Post by **Thirsha42** » Sun Jun 30, 2019 8:38 am

The big problem is how do you make the button without creating a puncture risk or damage to the skin. I was playing with the idea of magnets but got nowhere.

abbadon31 · Post by **abbadon31** » Sun Jun 30, 2019 4:11 pm

If the button is large and flat it wouldn't make a puncture point

Maviarab · Post by **Maviarab** » Sun Jun 30, 2019 4:22 pm

But it would if it was inside the TPE. if you posed her/moved that joint a lot, the TPE wouldn't last a month.

It's a nice idea (that would massively up the cost and breakage risk) but the TPE just wouldn't be durable enough unfortunately.

david 68 · Post by **david 68** » Sun Jun 30, 2019 6:20 pm

not a bad idea, that would really spice up the loose and tight joint issue. :drinking:

bob444 · Post by **bob444** » Mon Jul 01, 2019 9:44 am

Great idea. Perhaps an electronic switch would work. They could be wired to a small control panel or even better operated with your smart phone.

MannyCan · Post by **MannyCan** » Mon Jul 01, 2019 3:13 pm

This has been tossed around before .. but no manufacturer has taken the concept into reality. Would be nice.

abbadon31 · Post by **abbadon31** » Tue Jul 02, 2019 1:23 pm

Maviarab wrote:But it would if it was inside the TPE. if you posed her/moved that joint a lot, the TPE wouldn't last a month.

It's a nice idea (that would massively up the cost and breakage risk) but the TPE just wouldn't be durable enough unfortunately.

Really then why is my camera flash still working after 20 years of use with the same thing in it and its made of plastic parts.

Maviarab · Post by **Maviarab** » Tue Jul 02, 2019 1:24 pm

abbadon31 wrote:
Maviarab wrote:But it would if it was inside the TPE. if you posed her/moved that joint a lot, the TPE wouldn't last a month.

It's a nice idea (that would massively up the cost and breakage risk) but the TPE just wouldn't be durable enough unfortunately.
Really then why is my camera flash still working after 20 years of use with the same thing in it and its made of plastic parts.

Maybe because it doesn't have a thin layer of TPE over it maybe

abbadon31 · Post by **abbadon31** » Tue Jul 02, 2019 2:11 pm

No but it can hold 9 pound in 30mp winds

jm6o8u · Post by **jm6o8u** » Tue Jul 09, 2019 12:09 pm

Here is the post I stared in nov.28-15. https://www.dollforum.com/forum/viewtop ... =6&t=67035 Reforesting the tpe or silicone would do the trick.

BuilderOfCastles · Post by **BuilderOfCastles** » Tue Jul 09, 2019 4:41 pm

I am all for this concept working...

however, i am here to tell you why this proposal won't work.

abbadon31 wrote:
Maviarab wrote:But it would if it was inside the TPE. if you posed her/moved that joint a lot, the TPE wouldn't last a month.

It's a nice idea (that would massively up the cost and breakage risk) but the TPE just wouldn't be durable enough unfortunately.
Really then why is my camera flash still working after 20 years of use with the same thing in it and its made of plastic parts.

The first half of the answer is torque.

Your camera flash is holding a couple of pounds at a few inches. So, probably 3 inches * 2 lbs or 6 inch-pounds
The doll, at the knee is hold a dozen pounds at over 18". So, probably 18 inches * 45 lbs or 810 inch-pounds

And you will be working with forces 100x greater in a joint that is approximately the same size.
Which means you no longer get to use the bevelled teeth that mesh so nicely and easily, but probably full on square teeth out of machined and hardened steel. NO injection molded ease. No stamping ease.

Further, you will still have to use a stronger spring.
The thing that works so well on your flash is that it has a very solid button and lots of range to push.
The joints on a girl are tiny, and you are trying to press a button through TPE (rubber).
And the rubber has to take this and say, more please.
While your finger has to not only press the rubber... which does nothing but take up force
but finally depress the button.

I have been working on pneumatic switches embedded under TPE and am having trouble with durability.
(Far less force required)

- -- - - -
Next piece is that most joints are not singular, but are two way joints. So, you need two buttons... two everything, and the pain is that although one button is easy to visualize positioning in the knee, where on earth do you position the buttons (plural) in the hip joint?

I have, so far, been unable to answer these questions.

Some ideas i have worked on are locking knees... like on a human, especially girls, they bend their legs slightly backwards and lock their knees when standing. This seriously lowers the amount of force the joint needs to resist. However, if you move the knee a little bit forward (like brushing up against your cutey), the doll suddenly falls to the ground.

pitspoes · Post by **pitspoes** » Wed Jul 10, 2019 7:00 am

Thanks you posters and viewers for looking at this subject.
& commenting how it can be done, facing problems and why it can not be done.

I would want a big button that can be pressed like a pen with no force at all.
A pen where you pressing hard on the pen will not move the pen inside.
Only pressing the button with little force can move the pen back inside.

If we use the teeth wheel from abbadon31 then more teeth will make the limited positions it can stay in greater.
and using a steep angle or no angle (block teeth) There is almost no force needed to keep the joint locked.

Like BuilderOfCastles mentions this only applies to 1 dimension joints. not ball-joints.

Keep it up