Ronan's Shoulder Piston

[Ronan]

Ok here is is.  The bad boy that I designed.  I'm going to call it a piston for lack of a better term.  Plus when I paint it, it will look like a piston.  There are no stress points and it has great mobility.  I've added videos below.  It costs about $10 and all the pieces can be bought at your local hardware store.
The plate that goes under the shoulder.  It has 3 holes. 2 bolts hold it to the shoulder.  the 3rd is for mounting the piston.



Here it is.  I'll show each section below.

Exploded view


Take a 1/2 in PVC non threaded end cap and cut off the top.

Take a 1 1/4 end cap, drill a 1/2 hole (it should be just slightly smaller then the small endcap) and also drill a hole all the way through so the pin can slide in.

Then take a bolt (I used a 1/4) and slide i through the small cap, add a spacer, a big washer, locking washer and a nut.  You now have the ball jont.

Now attach that to the shoulder and cut off any extra of the bolt sticking down.

[Ronan]

On the inside of the bell, glue a 1/2 in cap inside a 1 in cap.  Then glue that inside the bell.  I found the bigger cap give more surface to glue it to the bell.

Take a piece of 1/2 in and a 1 in PVC pipe piece and cut them into points.  Then drill a hole through each one.  Then slide a 1 1/2 in bolt thought them.  It shoul dbend like an elbow.  Them get a 1 1/4 in to 1 in reducer and drill a hole through it as big as the pin from earlier.  You will want to put the reducer in the 1 1/4 in cap and the drill.  It will insure the holes line up.

This is showing the 1/2 cap on top, but really it will be glued inside the bell.


So now you will have an upper part that includes the shoulder, pvc caps, small elbow joint and the 1 1/4 -1 in reducer.  The bottom will be secured to the shoulder and that will be the ball joint.

[Ronan]

Here are the videos

Its a little dark, but here is the mobility test

Mobility

Here are each section of the piston.
Ball socket
Elbow Joint
Upper Section
Aligned
Connected

[CLOTHAR]

Great idea there Ronan.  It looks like it works really well.  I will keep this in mind for next time I upgrade my suit.  Thanks for sharing.

[Rraijjar]

Nice and dirty, but very usefull! thanks for sharing

[ViolentDream]

Awesome idea! May adopt this soon if the door stopper I installed as the pauldrons' connection to the torso fails.

Thanks for sharing, Ronan!

[sangaire]

Love the idea and definitly gonna use it.  but question  instead of a cut piece of PVC for the top of the 'ball and join socket' could I use just a normal washer?

[Ronan]

You could use a washer, but it would cut more into the inner side of the big cap.  Using the smaller pvc cap, it is rounded and slides better.  More like how a real ball socket works.  At least the ones I have are rounded.

[sangaire]

Well I got all hte parts today and I will be posting prices of everything as I got it from lowes to help those that want jsut a basic list needed for both sides with ammounts and prices and names (part numbers as well.)

[sangaire]

How do you keep your's from falling to the side? mine seems to pull down and out from my torso.

[Ronan]

How do you have your arm connected?  Is it connected to the bell or the chest piece?

[sangaire]

Sorry should have clarified I meant for the shoulder piece not the arm.  The piston on mine seems to slope out https://scontent-b.xx.fbcdn.net/hphotos-ash4/1394328_664692886894396_1861124478_n.jpg look on the left shoulder pice how mine seem to just drop off to the side.  any clue how to fix this?

[Grove.of.Dreams]

The shoulders are bowing out like that because they're heavy and nothing is stopping the 'piston' from obeying them (and gravity).  As for the arm vs. shoulder thing, I think he was asking because how you position yourself inside the suit can affect how the suit flexes and moves.

In this particular case, I would bet that the 'fix' involves bracing the piston-devices.  Do you have any padding between them and your actual body?  Step #1 is giving the piston a flat, rigid surface to act upon (think of it being like trying to stand up and reach for something while on a water bed)...without the rigid surface, there's really nothing to hold the piston upright.  Once you solve that, Step #2....you need to make sure that this rigid surface is as close to level (that is, parallel with the ground you stand on) as you can get it).  It's not going to help you having a vertical mount if the mount itself is still slanted at 45 degrees.  Once you have the surface rigid, and the mount vertical, then (from the pic) I would say you need to either adjust where the mount attaches to the shoulder, or simply pad the inside of the shoulder so that there's more 'stuff' between it and the mount.  That way, it's not nearly so easy for the shoulder itself to pull the entire suit down.

As for specifics...if you take a look at Sylgian's build, he has a few great photos of how he reinforced the 'skeleton' of his chestplate.  This would help make everything less flexible (foam builds are squishy) and give the piston thing that flat, rigid surface to act on.  As for inside the shoulder itself...experiment?  Assuming you have some foam left over, just try building up the area around the point where the mount connects to the shoulder to lessen it's range of motion. 

[Ronan]

You can kind of see on my first pic.  I have a metal plate under the shoulder.  It has 3 holes.  The 2 closest to my neck have wide washers and bolts.  The 3rd hole is where I have the piston.  I'll see if I can get a better pic tomorrow.  But I'm redoing it all.  I'm going to build a ridged shoulder thing using metal strips instead of my suspenders.  Then going to have metal plates sticking out.  Everything will hang off them.  Then going yo make my chest piece kind of snap on using Velcro.

[sangaire]

I have a metal plate underneath the shoulder but it only has 2 holes and the piece if flat it might just be that I made the hole at hte bottom of hte piston too big? I will try and post pics soon. 

the suit isn't bending but the shoulder is at a slight angle so maybe if I repositioned the plate somehow to make the screw stand straight up? I don't know XD if it comes down to it I might just make a simpler design since I love this one so much.