Elwyn has suffered a grave injury :(

Jimbofod · Post by **Jimbofod** » Wed Aug 15, 2018 4:23 pm

Dollsampler, this is a great design and looks very promising! The diagram is super helpful and absolutely necessary for me, not being mechanically trained. Having a visual reference, I now understand your previous post as well. A bit longer spine would not hurt her at all. The flesh has plenty of stretch to it. I guess she might end up as a ~120 cm in the end.

The challenge for me will be getting these parts together, but it's doable I think.

I still don't know if the the lower spine piece is hollow or not. The end that connects to the hips is closed off, so it's hard to know. It is small and not readily detachable, so guessing by weight isn't possible. I have skyped Sanhui to see if their mechanics can advise on that. The closed off part is actually shaped like it was cut out from the top of the U-shaped hip where it connects. To me, this suggests the lower spine piece is probably hollow to make the original construction of this junction easier to do. Otherwise they would have to cut the shape out of a solid tube instead of a hollow one. Also, it's a small piece, but I would assume they would generally prefer to use hollow pieces as a way of keeping the doll's weight lower.

Dollsampler · Post by **Dollsampler** » Sat Aug 18, 2018 4:22 pm

The best way to find if it is hollow is to make a hole in it preferably by using a kind of dremel.

Jimbofod · Post by **Jimbofod** » Mon Aug 20, 2018 8:49 pm

I was looking at the part again, and it's really very short. Even if I can make a hole, it could only be of very minimal depth, and I'm thinking the width would not be much either, so the vertical bar support might have to be pretty thin. Would it just be better to use a wider bar support and forgo the hole? Which is more important, the hole or a thicker vertical support?

If a hole is really better I will have to buy a dremel to find out if the part is hollow. Do I need a particular power level of the dremel or a special bit to get into stainless steel?

Another question: is there a particular type or brand of epoxy that is stronger than others?

Thanks again!

zaxdoll · Post by **zaxdoll** » Tue Aug 21, 2018 3:22 am

all i gather about silicon glue was silpoxy as the ref, to be verified, never used

Dollsampler · Post by **Dollsampler** » Tue Aug 21, 2018 6:08 am

For the époxy putty you may find it at diy stores.It must be the pasty putty made of two components to mix together. You read the instructions and choose the higher strenght one.
If it is a problem for you forget about the double interlocking system. Provided the spine piece and the interior of the junction pipe piece (you can use an inner threaded pipe also (plumbery department)) are grooved for époxy adhesion a simple interlocking system will hold well.

Dollsampler · Post by **Dollsampler** » Sat Aug 25, 2018 6:33 am

If I understand well there is a hole in the horizontal hips pipe at the location where the spin piece was welded?
If that is the case now I understand why you see the spin pîece as beeing closed with a end bulhead shaped like the hips pipe bulhkead.
What you probably have there is the bulkhead portion of the horizontal pipe which has been teared out when the Weld broke.In fact the fact of welding too deep in the hips pipe has ruined the bulhead resistance. Cracks started there and with time there was a tearing off.
Welding pipes (vertical with horizontal and with small thicknesses) without unterlocking them is a great mistake because if the welds are too deep the horizontal pipe bulkhead loose its thickness in the way of the Weld seams.That is what has happened here and should happen very often.When pipes are jointed by interlocking the Weld may be lighter in depth as the flexion stress is not directly applied on the Weld.

Jimbofod · Post by **Jimbofod** » Sun Sep 02, 2018 10:01 pm

Dollsampler wrote:If I understand well there is a hole in the horizontal hips pipe at the location where the spin piece was welded?
If that is the case now I understand why you see the spin pîece as beeing closed with a end bulhead shaped like the hips pipe bulhkead.

Yes, this is the case. Here is a photo of how the end looks (with a metal ring around it that I will explain below).

: ring and spine closeup; 20180902_195137.jpg (408.77 KiB) Viewed 2459 times

Today I went shopping to see if I could find parts that fit your repair design. The upper part is so short that I decided not to try bothering to drill a hole in it. If I did that, the hole could not be very big, so the supporting rod that would fit into it would also have to be narrow to fit into it. I supposed that a thin rod would not be as supportive and would leave a lot of space between it and the outer pipe. I redrew the schematic focusing on the measurements I needed for the two parts (rod and ring).

: schematic.jpg (1.04 MiB) Viewed 2459 times

Sorry this photo came out sideways here.

I made these measurements to work out what might be the ideal sizes for the inner support rod and the outer pipe/ring. First I measured the diameter of the upper "spine", taking into account the wide bit that tore off from the hips. (The outer pipe/ring would need to have an inner diameter slightly bigger than this so that it could fit around the spine.) This width was about 28 mm or 1.1" measured by digital calipers. Then, I wanted to know the length from the hip-connection end to just where the actual ball joint is. I would not want the outer pipe/ring to go above this and restrict movement. This length was about 33 mm or 1.3". (After bothering to take both units of measurement, the only one that mattered when I got the store were the empirical ones - inches. And of course it was not something like 1.3" but fractions like 1 and 1/4".)

For the inner pipe, I wanted to know the ideal length and outer diameter width. For the length, there was about 0.8" or 21.0 mm of depth into the hole. I supposed that I would not likely find something of this exact size, but that it wasn't far from 1", and an extra 0.2" of height added to the doll would not be an issue as long as it still fit well into the support structure. For the width, I messed up and used the width above which corresponds to the widest part of the oval-shaped opening in the hip tube (1.1"). More on this below, but I went out assuming that the rod width could be 0.8 to 1.0" and be ok.

It's Sunday, so all of the smaller specialty shops were closed. I went to Home Depot and the plumbing section. There were interesting parts I figured would work well. I asked the guy, and he said they didn't offer to cut anything there, that I'd have to do that at home (Ha! That means I'd need to find another place to do that for me.) There were some parts and fittings though that looked like they might do the trick without the need for getting custom cuts. I started off looking at brass pieces but later found they had black steel which I assumed would be better. There were some I thought I could work with.

For the outer pipe or ring, I bought a steel coupling that is just over 1" in inner diameter and about 1 3/4" long. This part looks to be a success. When I got home and put it around the spine, the flared connecting end fit through just fine. Actually, when I lined it up to about the ideal spot just under the ball joint on one end, it extended just beyond it, so it might be just slightly long. I think this would be fine especially if the inner rod is also a bit long.

: outer ring fit.jpg (623.74 KiB) Viewed 2459 times

: ring view 1; 20180902_194726.jpg (544.49 KiB) Viewed 2459 times

The inside is nicely threaded and should aid "locking" it in place with the epoxy.

: ring view 2; 20180902_194728.jpg (651.17 KiB) Viewed 2459 times

For the inner rod, I bought a steel "pipe nipple" that is about 1.5" long and 1" in outer diameter. It was also almost fully threaded except a small bit in the center.

: steel nipple (too wide); 20180902_194732.jpg (532.99 KiB) Viewed 2459 times

Unfortunately, this steel nipple does not fit into the ovular hole of the hip joint because I did not measure the narrowest part of the oval, so I will have to go back for something else that is narrower.

A better candidate might be this brass piece (or a steel version if available) that I took pic of but didn't buy. It's just over 1" long and is 3/4" in outer diameter.

: brass nipple; 20180902_182141.jpg (568.95 KiB) Viewed 2459 times

Actually, it may be a bit short in length, but I'll probably get it and see how it fits anyway. I can probably return what doesn't fit. If not, it's only a few dollars lost.

While I was there, I got some course sand paper for when things look like they will all fit together properly. For the epoxy, I found the highest strength 2-part epoxy available that came in a convenient injector package. They had a larger volume set that was more than I needed. I think this much will be enough. I also grabbed some work gloves on sale and a small paint brush for maybe helping to keep the epoxy in place after applying. I'll probably test a small amount out first on a paper plate to see how well it works and get familiar with it.

: other supplies; 20180902_212950.jpg (924.42 KiB) Viewed 2459 times

For de-greasing, I have some WD-40, or I read that vinegar also works. I think I should line the inside of the area with something first though because I don't want de-greasing solvent or the dirty grease itself messing up the silicone flesh.

If I can get an inner rod part that fits well, I think I should have all the things I need for the surgery.

Jimbofod · Post by **Jimbofod** » Mon Sep 03, 2018 2:07 pm

A quick update on my test of epoxy...

I squeezed out a small amount onto a paper plate. In the package was a small wooden stick for mixing. Man, does it small terrible! I left it out on the back steps to dry in the sun with the stick propped up. The cure time is supposed to be 5 minutes, but I left it out there quite a bit longer. As you can see, the stick is help up pretty sturdily by just this small amount. When I bend the plate, the epoxy puddle can flex and doesn't crack. As you can also see, it got very runny. The solution is not terribly viscous at the start. If you are used to repair silicone or even silicone 2-part mixes, those are far more viscous than this. I think I would modify Dollsampler's design to use cotton balls as stoppers in the legs instead of just a bit a of paper, maybe both. Otherwise I think the stuff is likely to run down into the legs and away from the center where I want it.

: 20180903_133718_HDR (2).jpg (593.75 KiB) Viewed 2439 times

Hours later, it still stinks, so I'm keeping it out there until I probably take it directly to the dumpster. Somehow, it seems the odor tends to "stick" to things, so I will have to consider now carefully where I do my actual repair which will use a good deal more of the stuff. Probably I will pick a room and isolate it off with its windows open and fans blowing in it for hours if not days. I would do it outdoors, but I don't have a safe place to leave a doll body outside for even a short period of time. It is actually bad for you to breath or touch, so I guess it's better that it is detectable by smell. I hope the doll won't smell bad forever afterward. Probably it will be fine after sufficient ventilation and then sealing up the wound.

I will probably take a crack

at seeing how much force it takes to crack the epoxy later on. I'm curious how long it will stay smelly as well.

I still need a part to serve as the internal support rod. Maybe I will get impatient and go pick it up today. Otherwise I'll grab it on the way to work one day this week. I wonder if I should pre-epoxy the rod and ring parts together once I have them. That part I could do outside without a problem, and then it might make the final installation easier as well. Because the inner rod now has to be considerably more narrow than the outer ring, I don't think a weld is possible unless maybe some connecting pieces are used.

Jimbofod · Post by **Jimbofod** » Mon Sep 03, 2018 2:14 pm

About that inner rod...

Instead of using something like the piping "nipple", maybe I could find a bolt of suitable size.

: 20180902_181033.jpg (875.69 KiB) Viewed 2438 times

The narrow end could go into the hole of the hip s, and the top would be the larger head and fit more snugly into the ring. The bolts I saw were mostly nickle, so I assume steel and nickle are not easy to weld together, but even for joining them by epoxy, this might work better.

Dollsampler · Post by **Dollsampler** » Wed Sep 05, 2018 5:47 am

Hello Jimbofold,
Your plumbing piece look good.
You can use a bolt to joint the hips pipe with the plumbing pipe. The bolts have a coat of zinc or nickel but are made of high tensile steel. The epoxy will have strong adhesion thanks to the threads of bolts and threads of the plumbing pipe.The spin piece will have adhesion thanks to the irregular teared off upper hips pipe wall piece and to sandpapering it elsewhere.
Your bolt (minimum diameter Metric 10 but the more the better) will have a lenght such as to enter at least 15mm inside the plumbing pipe (the more the better) and touch the spin piece with its head and on its end to touch the lower wall (not teared away) of the hips pipe.

To assemble all together with époxy resin will be quite difficult (especially for the right positionning) in situ so it would be easier to do it in three step (with 24 hours curing between each)
First assemble outside the doll the plumbing piece with the bolt head side (be carefull not to overdo with époxy quantity to let space for the two further cold welding at both ends of the bolt)
Then assemble the bolt end of the hybrid junction piece with the hips pipe. Press well époxy Inside the pipe (using various wood sticks) the hips pipe must be filled with époxy at least up to one cm both side of the hole. The plumbing piece must be well glued on its base with the pipe wall/hole Try to have no void.Seeing époxy overflowing here and there is the best.

Finally the easiest would be to enter the spin piece Inside the upper part of the plumbing pipe and have époxy overflowing there.
After 48 hours of curing you will be able to manipulate the doll again.

You have here the advantage that your spin piece is a pipe because the spin hinged joint skeletons have an U piece welded on the base to the hips pipe wall and in case of such wall tearing off breakage are not repairable by cold welding.

Jimbofod · Post by **Jimbofod** » Wed Sep 05, 2018 9:01 pm

Dollsampler, thanks for the feedback and advice!

I am considering one of two bolts that I have right now. One is a perhaps a bit long and ends up stretching her to slightly taller height but definitely connects between the two pieces. The other is possibly a little short causing the outer ring to be pushed up a bit higher than I might like and close to the ball joint that I hope will still be functional afterward. I'm leaning toward using the longer one just to make sure there is a solid connection.

For the first part of the construction (the bold/ring hybrid) I am actually facing a challenge of holding the bolt in the right position vertically and also in the center of the ring. The bolt head diameter measures at 21.6 mm at the max (corner to corner of the hexagon), and the ring's inner diameter is about 31 mm. I could find larger bolt heads, but they come with much longer bolts. I have an idea to use some putty to hold it in place and also form a bottom, like a cup, for the epoxy. Once the epoxy cures, I could remove the putty and throw it away. I think this will work to get the bolt in just the right position inside the ring - in the center and with the small end protruding sufficiently (but not too much) so it can be glued in to hip hole. The putty may also be useful in later steps. I will get some and first make sure there is no unexpected chemical reaction between it and the epoxy. Man, the neighbors are going to love me!

Meanwhile I am devising a plan for how to set up a room for the epoxy curing (that I will mostly stay out of until the process is all done). It will take some moving things around and probably changing where my window AC goes, but Ellie is worth it! I noticed the epoxy still smells days later, so I hope that won't be a problem long term. I may need to let her air out for a long time before sealing her back up.

Also, the epoxy doesn't crack but can bend, which is very good. I'm glad I did my paper plate test to better understand what to expect.

Dollsampler · Post by **Dollsampler** » Thu Sep 06, 2018 6:09 am

The fact that your époxy bend worries me a little bit. What is the tensile strenght indicated on your epoxy package? It must be above 200 kgs/cm2. The more above the best.

Also take a bolt with a head of about 30 mm. If it is too long they can cut it at the shop with a sand disc tool.Dont use putty to position pieces use steel nails that will be secured by the époxy and will reinforce the interlocking.

Jimbofod · Post by **Jimbofod** » Thu Sep 06, 2018 8:47 pm

Hi Dollsampler,

I understand your concern, but the amount on the paper plate was very thin, so bending the plate would mean for sure it would either bend or break. I would be more worried if it cracked and broke. The package states that the strength of the epoxy is 4400 psi (pounds per square inch) which coverts to about 309 kg/cm2. This was the strongest one on the shelf among a few other options.

I'll have to look for another place that can cut a bolt for me. The guy at Home Depot said they wouldn't do it. There was a saw there, but I guess maybe they only do it for non-metal pieces.

I'm a little confused about how nails would be used to position the bolt in place. Would you mind maybe drawing a little diagram to illustrate?

Thanks!

Dollsampler · Post by **Dollsampler** » Thu Sep 13, 2018 8:35 am

Hello jimbofold,
Your époxy resin at 309 k/cm2 is strong enough.However that is one tenth of the admissible tensile strenght for good bolts for example.that is why the bolt with 30mm head will transmit its torque trough a greater surface of époxy than a 22mm head bolt.