Saturday, 28 November 2015

Repairing One of Those Pesky Broken RAH Shoulders

Hello, everyone!

It has been a looooong time since I posted here, but I assure you, my return isn't motivated by frivolity. No, ladies and gentlemen. This time I'm on a mission.
An important one.

Today I will be repairing none other than
this dismembered Plastic Torso!
No, seriously...

The torso used to be a part of Medicom RAH (actually "Real Action Heroes") Roy Mustang, but as you can see, the shoulder is broken. Roy's broken parts were graciously replaced by Medicom Toy a couple of years ago, but I'm going to be fixing the broken shoulder on the left-over torso anyway.
The reason is this guy:

Meet Medicom RAH L.
I get a lot of weird questions about a lot of weird figures, but this guy tops them all. I've had more questions about RAH L than any other figure.

To sum up, your standard RAH body has approximately one zillion Chinese-puzzle-box-like moving parts, which makes them delicate to start with, but some of the older RAHs like L go beyond mere delicateness – after a while, the plastic around their joints actually starts to crumble of its own accord.
This means that one day you're happily going about your business when suddenly your most beloved, most prized, most expensive action figure's ENTIRE ARM just FALLS OFF.

I've said it before, and I'll say it again: *HYSTERICAL SCREAMING*

This – along with accidental decapitation – 


– is the most common RAH problem people ask me for help with. And I know my readers aren't making it up, because this is exactly what happened to my RAH Roy Mustang (after I put his head back on), and it is MIGHTILY DISTRESSING.
Don't feel ashamed for crying, ladies and gents. You're not alone.
So, short of replacing the parts, what can we do about it?
Answering this question took a fair bit of experimentation, but – EUREKA! I finally found a satisfactory solution.

This is where it gets Technical...
The main cause of all the anguish is this thing:
The Thing, shown here next to a tiny washer.
This peg used to hold the shoulder on, but now it doesn't because the cone of plastic it used to be embedded in has disintegrated.
But what's so bad about the peg itself?
At first glance, it seems rather like an innocent-enough screw, but look carefully at the shape, and you will see that it is actually an itty-bitty-super-fiddly RATCHET. The only way this ratchety little S.O.B. could have been inserted in the plastic in the first place is if the shoulder-plastic was heated until it was soft (or it could have been done with a tonne of pure, unadulterated force, which you'd think would break the plastic, but I could be wrong).
Now, I'm reverse-engineering all this, so I may be mistaken, but I'm guessing that pushing this knobbly chunk of metal through the hot plastic is probably what weakened said plastic in the first place and later went on to cause the infamous crumbling we all know and love.
So here's the question:
How the heck can we get the peg back in!?
The answer is:
We can't.
The plastic which used to hold the peg in place has now crumbled away, and even if it hadn't, the temperatures required to heat PVC to a point where it's soft enough to work are not all that convenient (and now that the plastic is a few years old, a tonne of pure, unadulterated force would definitely be out of the question).
So I'm going to show you how to modify a screw to act as a replacement shoulder-peg.

You may want to have the broken pieces with you, so you can see what I'm talking about.


1. Needle-nose pliers
2. One (Self-Tapping) Screw (approx 2mm diameter)
3. A Ruler
4. A Hot Glue Gun OR Epoxy Putty
5. A Pin Vice
8. 2mm diameter Drill Bit
9. A Regular Size Phillips Head Screwdriver
10. A Small Size Phillips Head Screwdriver


11. Sandpaper
12. A Big Sewing Needle
13. Scissors
14. Forceps
15. A Hairdryer

16. Bandaids

Part One: Replacing The Peg
First of all, get the metal peg out of the shoulder. You can do this by pushing it from behind (on the ratchety end) and then wiggling it out with pliers.
It should have a small washer on it (pictured above). Keep that washer safe. You're going to need it later.

NOTE: There's a possibility that the shaft that contains the head of the peg will be covered by what I'm going to call a "blocker". These are put in place for aesthetic purposes, but for us tinkerers, they're just in the way.
Blockers are made from soft plastic and not usually glued in. I personally remove them by stabbing them with a big-arse sewing needle and prising them out like so:
Note that the blocker in the photo is covering a screw, not the peg, since
my dismembered torso's peg-blocker was already removed.
With the blocker out of the way, you're free to remove the peg.

OK, now you've got that pesky peg out, the trick will be finding a screw which is about the same width as the original peg, but – and this is important – a few millimetres longer.
It was while pondering this that I realised I had kept a packet of small screws in my desk for the last five or six years for no reason.
*GASP* Could it be!?

Oh yah!
Had I not been so lucky, I could have just taken the original peg to the hardware store and compared it to the screws they had for sale until I found one with the SAME SHANK WIDTH.
Don't worry about the width of the thread, it's the shank which must match the original peg.
And speaking of the shank, make sure it is AT LEAST 10mm long (11mm is better). This is not including the head. You can see in the photo that the shank of the screw I am using is about 14mm long.

Anyway, something you may have noticed about the screw in the photo above, is that it is not only longer than the peg (good), but it also has a conspicuously wider head (BAD).

The reason this is bad is because the screw-head must fit down the narrow shaft from which you have just removed the original peg. What's more, it needs to be small enough to rotate freely within the shaft.
The shaft in the shoulder part. You can see by the comparative
hugeness of my thumb that it's very narrow. (If you're wondering why
 the edges of it look so mushy, my advice is to be careful with the pliers.)
If you managed to find a tiny-headed screw which fits down the shaft, good for you.
For everyone else, there's sandpaper.

Get a piece of regular woodworking sandpaper and file down the screw head, rotating it frequently, until it's small enough to fit down the shaft. This will take a little while, but it's overall not that difficult.
There will be some metal dust, so you might prefer
to do this outside.
Luckily, the screw doesn't need to be as insanely narrow as the original peg. Here's how the modded screw looks compared to an un-modded one:

Now you can put the tiny washer on the screw and fit it down the shaft.
You may find, as I did, that instead of rotating freely in the shaft, the screw threads bite into the plastic in the hole at the bottom of the shaft.
Instead of going around and around, in screws in and out.

This is a very tedious problem, but it can be fixed with some more tedious sandpapering.
The problem this time is the screw-thread.
Notice how the original peg is smooth at the top end, under the head?
Well, now we have to recreate this (roughly). Now we get the pleasure of REMOVING THE TOP 2-3MM OF THE SCREW-THREAD WITH SANDPAPER.
There are probably a bunch of ways of doing this, but here's how I eventually managed it:

1. Cut a very thin strip of sandpaper. About 3mm wide.
2. Using forceps, make a noose for the screw with the sandpaper, like so:
Note the position and orientation of the screw-head with respect to the forceps.
This will hold it in place while you enact step 3.

3. Pinch the sandpaper tightly against the screw-thread and, using an appropriate screwdriver, turn the screw around and around until the sandpaper looses its bite.
Pinching the noose.
4. Undo the noose, move the sandpaper along a bit so that a nice fresh, abrasive part of the paper is in contact with the thread and repeat steps 1 - 4.

This process will slowly grind down the top of the screw-thread until it no longer bites into the plastic. You may have to repeat it quite a few times (I know I did!), but it works.
And luckily, you don't have to grind the thread down to nothing before it stops biting.
Here's what my peg-replacement looked like after sandpapering:
Not nearly as smooth as the peg, but it still does the job –
IE It turns around and around in the shaft.
The tiresome screw in the tiresome shaft.
Alright, so now the replacement peg fits down the shaft (with the washer in place!), and can rotate freely!
We must be done, right?


The next problem is the length of the screw shank. (Sigh)
This must not exceed 11mm, and, as I mentioned previously, the shank of my shiny new replacement peg is a whopping 14mm.

Luckily, there's an elegantly simple method we can use to get that shank down to size!

Be sure to measure the length of the screw shank every once in a while between bouts of merciless sandpapering. When you've finished, it should be no more than 11mm in length, but no less than 10mm.
That doesn't leave very much room for unchecked merciless sandpapering error.
Once again, I will stress that the 11mm length refers to the SHANK ONLY! It does not include the head of the screw!
(For the purposes of this project, I couldn't give a rat's arse how deep the screw-head is.)
OK! Done!
The shiny new replacement peg can now fit down the shaft (along with the tiny washer), rotate freely within the shaft, AND it's 11mm long!

AT LAST. AT LONG LAST, we are finished modifying the screw!
Now, on to ––

Part 2: Modifying The Shoulder Joint
The broken plastic shoulder joint is made up of several fiddly pieces.
In this section, we will be dealing with what I'm going to call the Arm Part and the Fiddly Plastic Washer.
The arm part. This one looks particularly bad because I once tried to replace the crumbled plastic with yellow epoxy putty.
The Arm Part is probably attached to the rest of the arm in your case, and it contains the thing which is actually broken. As far as I can tell, where this ugly mushy break now sits, there once used to be a cone-shaped protrusion into which the shoulder-peg was inserted. This is, of course, now completely obliterated.
The Fiddly Plastic Washer. Note that it is different on each side. One side is concave (left), the other is flat (right).
The Fiddly Plastic Washer fits over the round depression in the Arm Part, with the concave side facing down:
Just like this. Note how it makes a little sort of cave.
In this section, I'm going to be filling up the little sort of cave made between the correctly placed Fiddly Plastic Washer and the Arm Part with hot glue from a glue gun. (You could also use epoxy putty, if you like putty.)
After the cave is filled, I'm going to drill a hole through the centre so that the new shoulder peg can be inserted.

Step 1:

Fill the empty space with hot glue.
This is pretty simple. Just squeeze the glue in gently until the hole is full. If you accidentally use too much glue, scrape/wipe off the excess until the surface is relatively flat (I used the big-arse sewing needle to smooth off my excess glue).
When you're done, it should look more or less like this:

If you're using epoxy putty, knead it up as per the instructions, then press it onto the broken surface of the Arm Part in a small lump.
Next, push the Fiddly Plastic Washer (concave side down) firmly over the putty-lump. This will mould the putty into the desired cone-shape.
Smooth off the top surface and remove any excess putty from around the edges of the washer with a craft knife or other scrapey tool of your choice.

Step 2:
This one's nice and relaxing: set your work aside until the glue/putty has set.

If you used putty, read the instructions to see how long you should wait, then add a few more hours to be safe.

If you used hot glue, then you just have to wait for it to cool down to room temperature.
In my case, this took long enough to have tea and crumpets and purchase some new laboratory glassware online.
I don't know what all the "popular" kids are doing with their lab glassware
these days, but I like to culture primitive land plants in mine.
Step 3:
In the Arm Part, there is a screw which runs perpendicular to the direction of the vague hole where the shoulder peg once was.

Before you do anything else, remove that screw.
It may be covered by a plastic blocker, but you can easily prise that out, as described earlier in this article.
Note that the screw is quite small, and you will probably need a small Phillips Head Screwdriver to remove it.

Once you remove the screw, you will be able to separate the shoulder part (which contains the break) from the rest of the arm (which in my case is dismembered).
This will reveal a brand new narrow shaft in the broken part.
It shall henceforth be affectionately named "The Second Narrow Shaft".
I just love narrow shafts, don't you?

Step 4:
Using a pin vice and a drill bit the same width as the screw-shank (in my case this is 2mm), drill a hole straight down through the middle of the glue/putty filling the Fiddly Plastic Washer.
The screw shank (not including the thread) and the drill bit are the same width (2mm).
Friendly neighbourhood pin vice, with the 2mm bit installed.
You can buy these at hobby stores, some hardware stores, and on eBay.
The above photo is an attempt to show (more or less) the angle you should be drilling at. At the bottom of the plastic part is the glue/putty filled washer.
Please note that the screw is shown in place in this image -- this was a MISTAKE! TAKE THE SCREW OUT BEFORE DRILLING!

This photo (directly above) shows the hole drilled through the middle of the fiddly plastic washer. Mine is a little off-centre, but it still worked.
Once again, note that the arm is still attached in this photo. This was a mistake on my part. When you drill the hole, remove the arm first.

Drilling can be a little tedious, because the bit will most likely keep getting jammed with plastic debris. Every time this happens, just pull the bit out of the hole, clear it off and press on.
Keep going until the drill bit comes out through the wall of the "Second Narrow Shaft".

NOTE: Drilling half-way is no good. I've been there, and I can tell you that neither hot-glue nor epoxy putty is strong enough to hold the replacement peg (or the original peg) on its own. You must drill through the plastic as well. The glue/putty is just there to add a bit of much-needed extra friction.


Part 3: Assembly
This is the last and thankfully easiest part of the whole saga.

First of all, make sure the tiny metal washer is fitted onto the modified screw like so:
And then insert the screw and washer into that annoying narrow shaft I talked about so much back in Part 1.
This again.
Now get your trusty normal-sized screwdriver and screw the modified-screw-cum-replacement-shoulder-peg into the hole you just drilled, reattaching the repaired shoulder to the torso.
Make it tight enough that you can work the previously-broken shoulder joint. The joint should feel reasonably firm, but not stiff. Remember, you want the figure's arm to move easily, but be firm enough that it doesn't fall down under its own weight.

Now some double-checking:
Looking through the drilled hole in the wall of "The Second Narrow Shaft", you should just be able to make out the tip of the replacement peg.
In most cases, these parts would still be attached to the torso.
If the peg protrudes into the shaft, take it out and sandpaper it until it doesn't.
If the peg is allowed to stick out into the shaft AT ALL, then the shoulder won't work properly. If you measured carefully earlier, then you probably won't have this issue.

Note that the less times you insert and remove the screw, the better, because each time you do, the joint becomes a little looser and more fragile.

Once the replacement peg is safely in place, all you have to do is slot the shoulder joint back together, do up that little screw you removed earlier et voila!

Yaaaay! The dismembered torso is slightly less dismembered than before!
At last! At along last!
Okay, now that it's fixed, a note on maintenance:
The replacement peg is fairly likely to come loose with time and shoulder-use. For this reason I recommend treating the shoulder extra carefully. However, if the joint does come loose, tightening the peg with a screwdriver should fix it.

*dusts hands*
That was the most complicated article I have ever written!
If you have any questions, feel free to ask me down in the comments section!

As always,
Good luck with your repairs!