knee joints

cptchris · Post by **cptchris** » Mon Jan 14, 2019 2:41 pm

Hi all,
Don't know if this has been mentioned already but I couldn't find it.
My 157b's knees are getting a little looser so she's getting harder to stand. Are these easy to tighten with a socket if I make a small incision or are they welded?
thanks!

jokerisalive · Post by **jokerisalive** » Mon Jan 14, 2019 3:32 pm

how long you had her?

Jakeelliot100 · Post by **Jakeelliot100** » Mon Jan 14, 2019 3:40 pm

Unless you delve into TPE repair and get good at it with some extra TPE DO NOT cut open your doll. Yes some people repair TPE but I am pretty handy guy and all my attempts have been terrible. I cut a small slit in the elbows of my MW to tighten joints and repair TPE. She now has gaping holes in her elbows. She was already pretty beat up and due for replacement when I tried this so I took a chance. TPE is almost impossible to repair....don't cut her!

That being said the facts that her knees are that loose already I think is unusual. My WM knees loosened up after maybe 1.5 years. They are now loose but I can manage to stand her. Very concerning to hear her knees are already loose....hopefully they don't get looser.

cptchris · Post by **cptchris** » Mon Jan 14, 2019 4:06 pm

About 7 months. I'm always posing her so don't know if if overused the joints?
I can get her to stand if I'm careful but they're more loose than they used to be. Just for comparison if I put her legs in the air the joints hold no problem but standing and taking the weight if I knock her leg she goes flying.

BWheeler1 · Post by **BWheeler1** » Mon Jan 14, 2019 5:11 pm

TPE is not impossible to repair. In fact, it's pretty easy. You said you ended up with gaping holes... my guess is that you used TPE solvent to close the cut. That stuff is like acid to TPE. Every time I've tried using it, things just got worse. I have found that the easiest way to cut TPE is with a hot butter knife. To close the cut, you simply heat the knife up again, pull the cut open, stick the knife in, and slide it out while pushing the cut closed. Hold it for about ten seconds and you're done. If it leaves a line, you can feather that out with a hot spoon. Just make sure to wash all powder and dirt from the area before starting. I had torn up elbows on my 140 and went as far as to cut the TPE away for a few inches to either side of the joint, make a form, and pour molten TPE back into the area. Aside from a few bumps from the form, it turned out way better than I'd imagined. I can finish it with a heat gun later, it doesn't bother me enough right now.

For the loose joints, try this. Find out from someone on here who knows (like grimreefer, he has a bare skeleton for reference) what size and type the bolts are. Also find out which side of the joint you tighten it from so you know where to cut. You can feel around and find the bolt then and know exactly where to cut. Then slice it there with a hot knife, tighten the joint, and close it again with the same hot knife (clean the TPE off of it before heating it every time).

dolln00b · Post by **dolln00b** » Mon Jan 14, 2019 6:22 pm

Yeah for some reason I can't make sense of not being able to fix small issues on the inside without damaging the outer layer. There needs to be a workable solution to this.

BWheeler1 · Post by **BWheeler1** » Mon Jan 14, 2019 7:02 pm

The sharpest razor can't cut TPE as clean as a hot knife. You get a nice, clean, straight cut. Which means when you close it back up with the knife, you get a clean seam. Like I said, you heat the knife again, open the cut, and put the knife inside the cut and quickly slide it out while closing the cut. The idea is to use both sides of the knife to melt the TPE on either side of the cut and when you slide the knife out, the two heated sides melt back together.

Seduced · Post by **Seduced** » Wed Jan 16, 2019 3:04 pm

BWheeler1 wrote:The sharpest razor can't cut TPE as clean as a hot knife. You get a nice, clean, straight cut. Which means when you close it back up with the knife, you get a clean seam. Like I said, you heat the knife again, open the cut, and put the knife inside the cut and quickly slide it out while closing the cut. The idea is to use both sides of the knife to melt the TPE on either side of the cut and when you slide the knife out, the two heated sides melt back together.

This is a really great idea.

I thought that the melting point of TPE is 160 degrees Celsius. I doubt your knife is getting the TPE that hot. It’s good to know that it can be worked with at lower temperatures.

BWheeler1 · Post by **BWheeler1** » Wed Jan 16, 2019 4:28 pm

Well, I've melted TPE to a liquid in a Teflon pot on my stove (the range hood and exhaust fan take the fumes out), and I heat the knife up using the same stove. You can hear the TPE sizzle and see it melt when you do it. You do have to make sure it's hot enough, not exactly red hot but hot enough. It's hard to explain, you have to kinda get the feel for it. Which would be a great job for a TPE test piece. Get one and try cutting it with the hot knife and fusing it back together. It works infinitely better than using that solvent.

Jakeelliot100 · Post by **Jakeelliot100** » Wed Jan 16, 2019 6:57 pm

yup...I used first the TPE "glue" which your right is just solvent that melts it all away and makes things worse. Then I tried a TPE repair kit but the process was much to complicated....and didn't work at all. Not saying it can't but it's not easy to do. Your hot butter method definitely sounds sound and doable. Thanks for sharing.

grimreefer24601 · Post by **grimreefer24601** » Wed Jan 16, 2019 7:18 pm

Solvent has it's place for the right repairs. I've used it a lot for repairs. Mostly for minor stuff only.

Heat is the way to close larger wounds. I use surgical tools to cut open. If I take my time I can get a good cut. Really sharp scissors work also.

All that said a WM is probably welded nut to bolt. That's likely your toughest problem. This is my Jinsan skeleton's knee. You'll have to cut this weld to tighten the knee. I'd grind out the weld and remove the bolt completely. Replace with a bolt and nylon lock nut. Other wise you have to make sure not to leave any jagged edges form the weld. Those will shred your doll, and make it worse.

: 20190116_171200.jpg (781.35 KiB) Viewed 2793 times

BWheeler1 · Post by **BWheeler1** » Wed Jan 16, 2019 7:56 pm

I never would have guessed that they would have welded that. Using a grinder will require a much bigger cut for access, along with the dangers of the sparks and dust from grinding getting into the TPE and possibly igniting it. In my experience melting TPE, it can ignite pretty easily and I'm sure the hot sparks from a grinder would do it. In light of this, if it were me I'd first try a small cut on either side and use two wrenches to try to snap the bolt or break the weld. If you use two impact sockets and two breaker bars, it should give you plenty of leverage to break the bolt. Then just like Grim said, replace it with a bolt and lock nut.

Or conversely, just leave it alone. My 140's joints are so loose after three years that when I pick her up she drapes over my arms like picking up an unconscious person. I can't lay her down and put her leg or arm in the air without it dropping instantly. All of her joints are loose. But I just posted a picture in the WM Dolls roll call thread with her standing with my other two. And she continued to stand there for about ten minutes with them while I posted that picture and a few others. I just had to lean her against something. It's possible, just takes a little more effort.

ColColt · Post by **ColColt** » Wed Jan 16, 2019 9:01 pm

I got my 140 girl back in May and to date she's been the hardest if not impossible to move her back from the waist either forward of back. The left leg takes twice the strength to move as does her right one. I don't guess I have much to worry abouit with her joints getting lose before mine will.

FeelingReality · Post by **FeelingReality** » Mon Feb 04, 2019 3:34 am

I just had to dig a hole in the side of the knee with a sharpened 6mm rod, to put a 16mm socket into it. It actually didn't damage as much as the back. But it is a bit too tight now. Very disappointed with this doll for the joints. Hardly used and it is just getting looser. I have only moved them about 30 to 50 times max to sit her down and lay her out on the bed. Folding her legs up to carry from room to room so not to destroy things on the way lol.

I am very much considering now, of redesigning the joints, and while there, putting in some actual knee caps with some PVC plumbing end caps of around 40mm to 50mm in my 165cm doll. I am thinking of some springs with a ratchet type clicking effect with a ball bearing under spring pressure for the joints themselves. I figure now, the best way is to cut in from the front and leave the back behind the knee still joined. I figure if I do it below the knee it will stretch to go back over the knee to expose it, and the cap I put in will have to be trimmed and mounted to one or both shafts of the legs either side of the knee. Then figuring once the skin is pulled back over it will be smaller end of the knee and less likely to want to ride up. But of course it will be rewelded with soldering iron on temperature control of around 220 C degrees. Since I have her in knee high socks it covers that. As with the long sleeves covering the wrist scars for the hand repairs. The back repair is out of sight and still a bit rough and am considering a larger soldering iron tip or custom made small shovel type, being an electronics iron.

I am actually considering a normal clothes iron to use the triangular corner to smooth out larger areas. I did try to repair a knee injury from being on her knees and having a fall, but first time at it, I didn't straighten it out, and so when i touched it with heat it got worse. But a clothes iron just for it, with some teflon coating, might work well yet. Since its a Chinese doll, sorry about the blasphemy, but being a heretic at it, I will learn enough to make it better than it is... its the 6 million dollar man all over again, though it only cost 1.2K delivered with 2 spare heads. But she is a great to cuddle and squeeze. And they do seem to come with the same faces I have seen on the more expensive doll sites. I mean I just like looking at a supermodel with everything in all the right places. A pity the VG is wider than it is tall, think I got a dud, and the sales rep in China said I was using it wrong and blamed me. So a bit of a zen moment to regain my temper. Its a bit of a bitch, when they don't speak English so well, and all I want to do is hold back from swearing. But one must work out their karma, lol. They were on a half priced sale at the time. So I do see these same dolls going for $3K AU.

FeelingReality · Post by **FeelingReality** » Mon Feb 04, 2019 3:51 am

Do any other dolls have knee caps and good knee joints that are NOT TOO TIGHT and DO NOT LOOSEN with use to bend and straighten them?

Has anyone designed or redesigned a better knee joint that perhaps uses a spring loaded ratchet system?

Thanks for suggestions in advance.