Shrinking Vinyl with Acetone--a head-y and hand-y experiment

[DISCLAIMER: Obviously, this thread is about acetone. While it isn't the most harmful chemical compound doll hobbyists use(MSC is far worse!), proper care should still be taken when dealing with it. Please be sure to read up on the risks before using this stuff, especially when using in large quantities as shown below. I don't claim to be an expert at this at all--I just wanted to share the results of my own experience. Also, this obviously pertains to the use of pure acetone on SOFT VINYL doll parts, not resin, not silicone, and especially not ABS! I'm not sure about the effects on silicone, but pure acetone does melt resin and abs. Finally, this will be a VERY long post with a small nsfw segment! Be warned!]

 

Since that's out of the way...

 

Are you interested in deka hands, but think they are too large for your girls? Do you want an MDD, but don't want their head to look too bobble-headed? Have you ever wanted to reshape or change the look of certain parts but didn't want to cut or sand it? If so, then this might be of use to you! It turns out that acetone can help you do all of this. I've spent some time testing the effects on acetone on vinyl to see if it can successfully be used to customize dolls in unique ways, and I think it could work if you want to try minimally shrinking and reshaping dolly parts. Keep in mind that results DO vary, and that once done it's practically impossible to restore the vinyl to its original size. It's incredibly experimental but that's what makes it kinda fun.

 

For those who don't know, shrinking vinyl doll heads are a thing in the fashion doll part of the hobby. This guide here by Dirili concerns MH dolls, but it's still the most comprehensive guide for vinyl shrinking I have found so far. I definitely recommend going through all of the info there before attempting this with your own dolls. There have been some Japanese doll owners who've tried something similar to this with their DDs, Obitsu, and other toys too. You can google "ソフビ縮小" (soft vinyl shrinking) and "ドール縮小" (doll shrinking) to see more. As far as dolls are concerned, it seems like this mod has only been done on heads, but this can be done on other parts as long as it's made of soft vinyl. Obviously you can't shrink down the joints and inner frames that are made from harder ABS/POM plastic this way.

 

The TL;DR version of this mod is that you soak the vinyl in acetone, wait for the vinyl to expand a lot, and then you remove the vinyl and wait for it to shrink. Basically, when exposed to vinyl for an extended period of time, acetone breaks down the plasticizers in vinyl. Or something like that. Plasticizers are what makes soft vinyl squishy. Others who've done this have left their heads soaking in acetone for as short as a few hours to as long as 4 days! After being removed from the acetone bath, the vinyl should be rinsed very well with water and left to dry for several days/weeks, during which the acetone that seeped in will evaporate. After all of the acetone is gone, the vinyl should be smaller and harder than it originally was because of the loss of plasticizers. You have to be careful though because not all parts shrink at the same rate.

 

What you'd need are:

- 100% acetone--not your regular nail polish remover.. unless you regularly use the super strong stuff meant to remove gel manicures, like this:

Most nail polish removers have dyes and other additives that we don't want. Actually I did opt for several bottles of this Onyx gel mani remover acetone, but you can also get larger quantities of acetone at hardware/home stores too. Just make sure it's 100% clear acetone.

- Water

- A large acetone-safe container with a lid big enough hold your vinyl piece and still be completely submerged.. and then some. A lid is important because you don't want the acetone to evaporate while your vinyl doll parts are soaking in it. Another thing to consider is that the mouth of your container has to be big enough to fit your parts through after they expand. I used a (new and clean) paint can from Home Depot when I first tried this with an 07 head, which worked fine at first. The bottom of the can started to get rusty after a few weeks though, which (probably) contaminated the solution. If you can find a large glass jar/container instead that has a wide opening, that would be much more preferable.

- Dolly parts you'd like to shrink.

- An area with good ventilation where your doll parts can shrink without being disturbed. Acetone fumes are pretty strong so you should keep your project away from high traffic areas in your home, at least for the first few days. Acetone is also highly flammable and so would your doll head or other vinyl part/s for at least several weeks so keep that in mind.

- Safety equipment is definitely recommended! Your respirator mask with an organic vapor filter will do you well if you're particularly sensitive to chemical smells, and rubber gloves would protect yourself if you use your hands to place and retrieve vinyl parts from the acetone bath. Personally I didn't use my respirator when I first dropped the vinyl into the acetone since you don't actually stay over the uncontained acetone bath for more than a few seconds at a time, and of course wearing a mask throughout the long drying period(weeks!) is impractical. But the plasticizers in the solution afterward DO worry me so I always used gloves and a mask while getting them out of the acetone and very thoroughly rinsing them down. So please use protective gear if you have them, and at the very least DO NOT inhale the fumes as much as possible and ALWAYS keep acetone soaked pieces in a well-ventilated area AWAY from an open flame.

 

From my experience using the ratio mentioned below, the amount of shrinking was noticeable, but not exaggerated. The shrinking amount can be controlled by the concentration of acetone in your solution, as well as the soaking time. The less acetone and the shorter the soaking time the less noticeable the shrinking effect will be, and vice-versa. You can experiment with this--I went with a 3:1 acetone:water ratio. Exactly how much you need depends on the containers you use and how big your project is. With my 1 gallon paint can I dumped three bottles of Onyx acetone in there and then filled one of the empty bottles with water, added that, and mixed it all up. This would yield about half a gallon of an acetone bath solution. With that done, you can get your subject/s ready.

 

Diving in headfirst

I posted this image a while back in another thread, but here it is again in the thread it was intended for. ^^

From L>R: SQ Lab Akane, DDH-08, DDH-09, and DDH-07, taken right before the experiment to shrink the 07.

 

As for precautions pre-soak, you should thoroughly clean your vinyl heads/parts first. Since my 07 was a blank one I only used dishwashing soap, which works fine. If they have a faceup I recommend removing it completely before soaking because acetone melts off faceups near instantly when undiluted, so it may still break down faceups even after being diluted. Dirili's guide mentions that slow soaking can keep faceups intact, but I haven't tried this with dolls with faceups yet so I can't confirm that it works the same way with larger dolls that were hand-painted. Maybe it could be done with Volks's prepainted heads which are similarly mask-painted, but testing that is too risky and expensive for me right now. In any case, paint/pastel/sealant/etc in the solution may cause it to get murky and lessen it's effect so it's safer to start with blank parts. I'd be really interested in seeing if shrinking a DD head with a faceup intact could work though.

 

Right after plopping it in.

 

Just 8 hours later! At this point I took it out of the solution. I did read up on Japanese doll owner attempts at this type of mod too, and they usually left their doll heads in for 1-3 days! However, instead of acetone+water, they used paint thinner instead. Paint thinner in Japan may be made from different quantities of different compounds than what I'd find in paint thinner available locally so I opted for a simpler mix that anyone could replicate and tweak. Even then, I could have left it in there longer than 8 hours! 12 hours or maybe even a full day would've been better for some actual noticeable results after the first soak & dry, but seeing the head I already thought was too big EVEN BIGGER scared me too much so I took it out of there before it got bigger lmao.

 

Some comparison pics with my 09 head.

It really expanded a lot lol The head cirbleepference went from ~23cm to 24.5cm after soaking for 8 hours.

 

One thing to remember is that at this stage, the vinyl gets verrry soft and squishy. After rinsing well with water and marveling at it for a while, you can set it aside in a safe place and wait for the acetone to evaporate. However, you can also try different things to manipulate the vinyl. For example if you wanted the head to be more wide or narrow you can use rubber bands and sponges or other stuff to squish it/add pressure to certain areas to make it look the way you want and make it stay that way for a while. Obviously you'd still be working off the original sculpt so it's kind of limited, but the option is there. Once it looks fine, leave it to dry completely and harden. Afterwards remove all of the rubber bands and whatnot and hopefully the head sculpt changed somewhat in the way you liked. The important thing is that you make sure that there is a layer between the vinyl and whatever you use to apply pressure, like a makeup sponge. I used rubber bands only at first and at the end I noticed faint lines across certain parts of the head where there was too much pressure from the rubber bands.

 

Stuff like that is fixable though! You could try to sand it out, but you can also dunk it back into the acetone for 1-3 hours for those lines to plump up again. This mod doesn't involve removing any material at all so the acetone will just make it revert to its original shape. You will need to wait some more for it to harden up again AND you may undo whatever manipulation work you tried in the first place, though you can just try again. Such a short soak won't really affect the total size of the head in the end, from what I can(or can't, tbh lol;;) tell. EDIT: It looks like using a hair drier on the lines fixes it too, without the need for a soak or sanding and with no effect to the shrinking that had already happened! It takes quite a bit of heat for it to go away completely but it works and is a lot safer... AS LONG ALL OF THE ACETONE HAS ALREADY EVAPORATED. Ofc Heat =/= Fire, but better safe than sorry... I only thought to try this now four months after the experiment and it worked just fine.

 

Anyway, after it dries and hardens and shrinks a bit(a few days to a week). You can decide whether it shrank enough or if you want to go through that again. After that initial 8 hour soak I ended up soaking it again for another 6 hours. However, it became clear that the headcap shrank more/faster than the rest of the head(I didn't take a picture of this at the time unfortunately) from the very first soak. Because of that, I removed the headcap and only soaked the rest of the head. For a 1/3 scale doll head it would take around 2 weeks to a full month for all of the acetone to evaporate, but the actual shrinking stops after a week or two from my observation. After that you just wait for the vinyl to finish hardening.

 

Fast forward to more than two four months later(this post is waaaay overdue), this is my 07 next to the same heads as before. I've since swapped her headcap(which was STILL too small) with my 09's headcap which fit much better, surprisingly.

 

L>R: SQ Akane, 08, 09, 07.. with my first attempt to make resin eyes. xD;; I also put the 'before' picture below.

 

No more huge-head 07! The cirbleepference of the head surrounding the headcap area is now 22.5cm. That part is still a little bigger than the rest, possibly because the edge of the headcap didn't allow for much acetone to seep in during the first soak when I kept the headcap on. If I separated the headcap, the head cirbleepference around there would probably be smaller by around 0.5cm to match the rest of the head. I don't think my pictures show the change very well, but her face is smaller now. I think it looks a bit more boyish compared to the mature/womanly feel from before?? idk xD

 

 

This is how her original headcap looks on her. It's brown now because I used it as part of my dye tests a few weeks ago, though that process didn't affect the acetone shrinking that took place months prior. Because of the acetone soak, it's way too small now and it just falls off. So for anyone interested in trying this, you may want to separate the headcap before soaking the head and soak it for much less than the head(just how much will have to be an experiment for someone else though). I think parts that were originally soft and squishy(like the new headcaps) shrink at a faster rate. Besides that, I'd say this head shrinking project was a success overall. ^^ I wouldn't attempt it with a limited head(not that that ever stopped someone), but I think it's a lot less scary with a standard head. I've heard that there is a limit to how much vinyl will shrink but I haven't tried finding out how long it takes to get to that point with heads since I was satisfied with how my 07 looked..

 

So with that out of the way, that brings me to the next part of my experiment: hand shenanigans!

 

First here's a comparison of some Obitsu and DD hands.

 

L>R: Obitsu 40-50cm, Obitsu 55/60cm, DD (regular), DD Deka (large)

 

Obi50 & DD deka hands

 

The type of hand pose isn't the same for each of them, but you can still see the difference! My girls so far are based on Obitsu 50cm bodies and those tiny hands bother me so much! Their sculpts look nice but they look too small in general for adult characters and are a pain to install on the wrist joints. -___-" So they'll be using DD hands instead. By this point I already did my head shrinking experiment before I ordered the rest of Elia's hands so I didn't hesitate to get the large versions instead if I liked the sculpt more... because I'd be shrinking them down if they looked too big. I got the regular-sized versions of the basic and loosely fisted hands, which look perfect as-is scale wise. As expected though, the large/deka hands on the other hand(?!) were significantly larger so I wanted to shrink them.

 

The large hands I'll be shrinking, clockwise from top left: Paper, Scissors/Peace, Pointing, Heart.

 

Some notes first:

- I'll be making a new acetone bath solution, of course! The old solution was kinda slimy(it's probably filled with plasticizers) and the paint can looked rusty and it's just gross. ^^"" Same ratio as last time--3:1 acetone:water. This time I'll be using one of those big 1 gallon glass jars of pickles instead of a paint can.. sans the pickles of course.

- I actually did try shrinking the heart hands before while I did my head experiment. I can't remember how long it soaked but I'll guess at least 6 hours. I did soak it after the 07 head and DDS bust so at that point I think my acetone bath wasn't very potent anymore. I thought there was a difference but after receiving my other large hands I don't really see it anymore since the heart hands don't look significantly smaller. LOL They do feel a little harder though.

- I think the scissors/peace hands look pretty alright(for the most part) scale-wise on my girl so I'll be pulling them out after 6 or 7 hours. The rest will soak for 5 more for a total of 12 hours.

 

After 7 hours. It looks bigger.. or maybe plumper.. I think? xD One thing I noticed this time because I used a clear jar as the container was that within minutes of first soaking the hands, some sort translucent substance was floating around in the solution. I assumed they were the plasticizers. I thought I'd be able to capture them when I took the 7 hour shot, but they kinda.. dissolved back into the solution before then?? o____o? I have no explanation for what that actually was and why that happens though. Anyway..

 

Scissor hands next to DD basic & Obi60 & 50 hands. I'm actually surprised to see it didn't seem to expand all that much? It's super squishy though!

 

After 12 16 hours.. I fell asleep so the hands soaked longer than I wanted. OTL We'll see how that affects the overall size after shrinking.

 

Paper hands next to scissor hands(after drying for 9 hours) next to DD basic hands next to Obi50 hands.. surrounded by everything else. I'm surprised I still don't notice much expansion????? The scissor hands didn't seem to shrink much at all too.

 

One day after starting the experiment. Not much of a change. The scissor hands seemed to have shrunk a bit more to their size before..

 

2+ weeks later! The large hands are now still bigger than the basic hands, but not as much as before. The change is very slight though lmao They're also much stiffer than before, especially the heart hands, which soaked the longest of all. I can still fit them all on the Obitsu 50 wrist joint I modded to be thicker, but it's a little tight for some of them. I'm sure that heating them up first with a hair dryer(which I should always be using in the first place tbh) would make it easier.

 

L>R: Obitsu 40-50cm, Obitsu 55/60cm, DD basic, Shrunk DD Deka Paper hands, unmodded DD Deka Paper Hands.

 

This is after more than a month later. I just got another pair of deka paper hands so I can see just how much these hands shrunk. It really isn't that much huh? xD Putting a modded hand next to an unmodded pair shows the difference best:

 

 

I'm pretty happy with how it is now though even with the rather small change. I don't think I'll dunk this set of hands into acetone again but I will do so with another set eventually..

 

YOLO experiment #1: Bust reductions

I never saw anyone try this while researching, but I did try soaking a DDS L bust in the acetone solution for nearly a day in one sitting(I just had to get too impatient at the 23 hour mark to make it a full day....), but it's probably not useful for most DD owners, hence why I didn't add "boob-y" to the title too. I tried shrinking it so I might use it on Elia, who's using a (mostly?) AZO2 Obitsu 50cm body. I liked her Azone I bust just fine but after seeing how the original DDH-07 head looked massive on such a thin neck/shoulders(of which I didn't take a pic... orz), I became worried that the 09 head I was going to get for her would look weird as well. I figured that I'd just try to not let it bother me if that was the case, but then I found a blog post showing a DDS bust on an AZO2 and wanted to see if I liked it so I ended up getting a DDS L bust last November. In person it looked good, but a tad big on the AZO2 body, and since I was already shrinking an 07 head I just YOLO'd it and dumped the bust in the bath for almost a day while the 07 wasn't in there.

 

This was completely unplanned.

 

I seriously regret not taking of picture of this bust right out of the acetone solution with my DDdy bust! It was much bigger AND squishier. For a while. But soon enough it became smaller(a bust cirbleepference of 23.5cm compared to ~25cm!) and really, really hard. RIP squishy boobs. Now it's actually so hard it doesn't really have any "give" if you try to squish it so I think it may have reached the limit for shrinking.

 

 

It looks nice though--like a DD bust scaled down a bit to match this body. It's very snug on the abdomen part, whereas before it was loose. For anyone with hybrid dolls with Obitsu/Azone/AP/etc bodies and DD heads, shrinking a DD bust to fit your doll body is an option if you want the look of a DD head with a DD neck/shoulders/bust on an Obitsu body. The size is supposed to be in between an DDS M and L bust, but it's still shaped like an L bust, which is kinda cool. It's also just tiny bit bigger than an AZO2 I bust, but still fits all of the AZO2 clothing I have. The big downside is that the neck and shoulders(and everything in general) harden so you'll lose a noticeable amount of mobility, especially if you're used to the thin and flexible vinyl used for the standard Obitsu bodies. It's a shame that she wouldn't quite be able slightly tilt her head to the side in the same way with this bust on.

 

This actually bothered me so much that I ended up just keeping her original Azone/Obitsu bust anyway, but I can always switch them out for the shrunk DDS bust if I really want the sloped shoulder look. If it was a shapely bust it could be useful for certain outfits but a super push-up bra effect isn't Elia's style anyway.

 

YOLO experiment #2: Expanding vinyl(without shrinking)????

 

Welp since I've gone this far and I have some Obi50 hands I definitely wouldn't use anymore, I figured I'd try to find out if it's possible to make them expand with acetone without making them shrink. I wasn't very optimistic, but I guess it was worth a shot. xD

 

After letting them expand, I stuffed the hands full with crumpled paper towels as tightly packed as possible. The idea is that I won't give the vinyl any space to shrink as the acetone evaporates. After a while I'll remove the filling and wait even longer to see if the Obi50 hands keep their larger size. This is all hypothetical. If anything I'm curious to see if these hands can get even smaller.

 

Obitsu 40-50cm hands. This camera angle hides my previous mod attempt disaster pretty well.

 

 

At least 2 weeks after soaking.. so stuff happened and I ended up leaving the hands in there for 2+ weeks! The acetone got really gross and murky. Ewwwww. As you CANNOT see(I had to fish them out first lol;;), the expansion is barely even noticeable! This is disappointing lol;;; The only difference is that the soaked pieces are much softer now, as always. Still, I figure that if it's been in the solution THIS long I'll be able to see how tiny it can shrink, if at all. I stuffed the fist and gripping hands very tightly with paper towels since they were the least mutilated by the previous wrist opening mod attempt. The rest will be left to dry normally. The normal/basic Obitsu 50cm hand did not get the soak treatment.

 

????More than 3??? Weeks later??

So the paper stuffing couldn't stop the shrinking at all. You may see that the areas near the openings are a bit bigger because of the paper, but everything else shrank. That being said, the actual shrinkage was barely noticeable. I left them in acetone for _two weeks_ so I think it's reasonable to say that vinyl pieces that were originally very hard and don't expand significantly while soaking in acetone will probably not shrink much at all.

 

I'm kinda sad that this yolo hand experiment was unsuccessful since I wanted to give those Obitsu hands another chance to be used the way they were intended, but they'll be going into the spare parts bin to be test subjects for future (dye) mod adventures instead.

 

Some final thoughts:

- (diluted) acetone will NOT melt away your DD or Obitsu dolls! So while you definitely don't want to leave this stuff on them for longer than necessary, it doesn't necessarily need to be feared too much.

- "softer" soft vinyl will shrink more and faster than "harder" soft vinyl.

- The more the vinyl piece expands, the more it'll shrink. If it doesn't expand in the bath anymore, it probably reached the limit for shrinking

- Vinyl that expands a lot gets superrrr squishy! It's almost therapeutic to squish it.

- The 3:1 ratio will yield results but it's unpredictable? It really depends on the vinyl itself. If anything I think my results were kinda underwhelming, especially in the hand department

- Heads take foreverrrrr to dry

- The acetone bath gets pretty gross(especially my first one, ew) after a while. I have to make a trip to the local hazardous waste disposal facility to throw it out sometime..

 

And that's all for now! I don't know if anyone will try anything here, or if anyone is even interested in this sort of thing at all lmao. I get very obsessive about small details so I'm always interested in learning about customization methods that could possibly achieve what I'm looking for. Sorry for the messy formatting and the gratuitous rambling for those that made it this far! Thanks for bearing with me.

This is very informative! Thanks for posting it. It's very interesting to see how much the 09 head has shrunk and it's good to know that this can be done if there a smaller faced sculpt that one wants. I don't currently have any but this is still very good to know and I think my husband says will try to experiment with other plastic types to see how it affects them soon as he learns about this. Anyhow, I hope to see how your 09 with her body turns out. If you have comparison shots, that would be great! Keep up the wonderful informative posts and experiments!

Thanks! I thought that this was a mod option that is off the radar for doll parents and customizers outside the 1/6 scale(and even there I don't think it's too well-known), so I wanted to test it and I think it can be somewhat useful. If it gives anyone any ideas for their own dolls or otherwise then that's great.

 

I think you mean my 07? I did shrink her head, but going by dolly plan priorities I technically shouldn't be focusing on her just yet. I'm kinda failing at that because I found THE perfect outfit for her and I'm not sure if it'll still be available later in the year(or even next year..). I might cave before then. xD I will actually post about my 09 girl's custom project soon(er), though! She's at the heart of my dye test right now. ^^ Fingers crossed it ends well! It's going nicely so far.

I am really looking into this, I am wondering is the method be possible for making mdd whit skin hands with shrinking of a small dd hand？ if it can be that would be amazing!

I am really looking into this, I am wondering is the method be possible for making mdd whit skin hands with shrinking of a small dd hand？ if it can be that would be amazing!

 

It's worth a try. Admittedly I don't know just how small MDD hands are compared to DD ones. Also note that everything shrinks a bit, including the openings at the wrists. Billy's pictures of his Nami with DD hands in this thread show that DD hands can look alright on MDDs as is(at least, in my opinion xD). But it may look even better if the hands were shrunk! Good luck if you test it out!

Great post! It's a shame the hands don't really change much, but the head came out really nice. The picture of the expanded 07 was almost a bit shocking to me. Since it's already a large head! Maybe it's because I've never seen a 09 in person?

 

The bust part was really interesting too. I think it looks really nice now, but it's shame the squishiness went away. Squishy vinyl is oddly very satisfying. Beauty means sacrifice maybe? lol. Either way, I'm glad that most of this went really well for you and it yielded some good info. Good luck with your jar of murky acetone though. I sort of dislike the smell of regular acetone, so I can only imagine what the mix smells like!

Great post! It's a shame the hands don't really change much, but the head came out really nice. The picture of the expanded 07 was almost a bit shocking to me. Since it's already a large head! Maybe it's because I've never seen a 09 in person?

 

The bust part was really interesting too. I think it looks really nice now, but it's shame the squishiness went away. Squishy vinyl is oddly very satisfying. Beauty means sacrifice maybe? lol. Either way, I'm glad that most of this went really well for you and it yielded some good info. Good luck with your jar of murky acetone though. I sort of dislike the smell of regular acetone, so I can only imagine what the mix smells like!

 

Thanks! I knew that my 07 would expand in acetone, but actually seeing it happen in person was still overwhelming.. even scary. I first thought that 09 would be on the smaller side of 8-9" before buying it based on pictures comparing it with an 07, but it wasn't and 07 noggins are just big in general. xD

 

Yeah, it is too bad that the bust hardened up that much. I wonder how soft/small it would have been if I pulled it out of there in like half the time. Acetone is totally not something you want to stick your nose in.. especially if it looks dangerously murky like what was in that jar! That being said, the smell of the indirect fumes while drying all of these parts wasn't that different from regular acetone.

Thank you so much for posting your findings! This was a really nice and detailed experiment!

I appreciate you taking the time to post your findings for us

 

Seeing the expansion of the 07 must've been crazy! That head is already huge!

Although it's one of my favorites!

@elianti For the hands - would you say that the hands shrunk to a fairly consistent size across the different pairs, especially the pairs you let soak for the same amount of time?

 

I'm tempted to try this with my large hands - I love them, but I wish they were a smidge smaller. Soaking them for 16 hours seems like it got them down almost to normal hand size; based on your photos. I'm thinking I would only soak mine for about 7-8 hours, since I'm looking for a sort of inbetween size - smaller than they are, but still bigger than the normal hands.

Edited January 14, 2019 by Guest

I always appreciate people willing to "go there" with their dolls. As someone who is a ""real science"" research student I will tell you that "fails" are as important as successes because without the failed test, results we cannot improve our results!

 

Thank you for sharing. I LOVE hybrids and have "complaints" about almost every doll body ever because I'm a snowflake who can never be happy and therefore always mod . This is really useful.

Thank you for you scientific research on shirking dolly heads! I found it fascinating.

I'm impressed by your bravery! Good job!