STAGE VIII :: Arm Pistons Concept

First, I flattened these nubs and drilled a small pilot hole in place of them.

:: See image 5 after shot...

NOTE :: The use of a drill press is highly recommended for some of the following steps.

 

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STAGE VIII :: Arm Pistons Concept

Next, I will resurface the other ends of these pistons. These are the ends where the aluminum rods are installed.

 
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STAGE VIII :: Arm Pistons Concept

Using a circle compass, I found the radius of the piston ends and marked the center for each peice.

 
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STAGE VIII :: Arm Pistons Concept

Here, I'm in the process of threading the cuff ends of the arm pistons. I typically use SAE 30 motor oil to help ease the thread cutting process.

The red arrow indicates where I've drilled a 7/16" opening for the aluminum piston shafts.

Here again, these parts will need to be polished up but I will deal with that later.

 
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STAGE VIII :: Arm Pistons Concept

As I mentioned earlier, at least one of the arm pistons will have to be modifyed to work with the cuff mount. The red arrow indicates where I've carved out a groove.

This is a good time to test fit your hardware. With mine, I removed the lower protruded keys for a better fit.

:: See image 1 before shot...

NOTE :: These pieces should never be glued in place!!!

 

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STAGE VIII :: Arm Pistons Concept

Here, I've test fit the piston with the mount in place. The red arrow indicates the newly carved clearance.

As for the other two pistons, fitting is close but there is no need to modify them.

 
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STAGE VIII :: Arm Pistons Concept

After making sure everything fits well, epoxy in the main beam of the arm to the cuff.

You may use either tape or rubber bands to hold the beam in place while the epoxy sets.

NOTE :: Be sure to install the base screw before the glue sets!

 
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STAGE VIII :: Arm Pistons Concept

When given the opportunity, I will go a little overboard on making an epoxy bond as strong as it can possibly be. Here, I've drilled a few extra holes for the epoxy to flow through when attached to the wrist plate.

By doing this, I've just created over 360 planes of bonding power.

 
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STAGE VIII :: Arm Pistons Concept

Here, I've carved in a little flow groove on the bottom of the wrist plate. This will help to releave pressure when these two parts come together.

 
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STAGE VIII :: Arm Pistons Concept

Thread the cuff to the elbow. This makes the perfect, upright stand for you.

Now, epoxy the hand in to place.

 
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STAGE VIII :: Arm Pistons Concept

Ball and socket joints between the arm and the wrist.

On the left, you will need to remove excess up to the first rib. The red arrows indicate these areas.

On the right, you will need to resurface and drill a 3/8" x 1/4" opening for the aluminum rods that come with the kit.

 
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STAGE VIII :: Arm Pistons Concept

This photo represents an early stage of the cleanup of these parts.

NOTE :: I've drilled a small pilot hole in each of the ball ends.

 
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STAGE VIII :: Arm Pistons Concept

Here, I've shaved off the upper hemisphere of each ball end. Cut three 10/32 round head screws like shown and epoxy them in place.

You should still retain a nice spherical shape with these parts.

 
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STAGE VIII :: Arm Pistons Concept

Epoxy these parts in place like shown. Each piece should line up with the screws heads on the top of the wrist plate.

 
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STAGE VIII :: Arm Pistons Concept

Test fit the socket ends to the aluminum rods.

It's a good idea to drill a release valve for the excess epoxy to flow through. The read arrows indicate these holes. You can always come back and fill them later.

 
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STAGE VIII :: Arm Pistons Concept

Test fit all of the parts. Thread in the screws only far enough that the rods line up to the angles that you need.

NOTE :: Only the bottom screw has been epoxied in place. The other three should not be glued!!

Once you have everything line up correctly, connect the arm back to the elbow and stand.

 
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STAGE VIII :: Arm Pistons Concept

A little modification to the arm piston ends.

Here, I picked up a few of those magnetic thingies found out almost any hardware or auto parts store. Cut the ends like shown and drill the piston ends to accomodate them.

I've made a diagram here to indicate a few depths. Epoxy the magnets in place like shown.

 
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STAGE VIII :: Arm Pistons Concept

With the arm in the stand, epoxy in place these newly magnetized piston ends. Be sure to wipe away any excess that flows out of the vent holes you created ealier.

Allow this to firmly set before proceeding.

NOTE :: Glue only the upper portions. The lower portions of the aluminum rods must move freely.

 
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STAGE VIII :: Arm Pistons Concept

Final stage of this assembly is a snap...

 
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STAGE VIII :: Arm Pistons Concept

...snap

 
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STAGE VIII :: Arm Pistons Concept

...snap!

You will not need to use any glue with these three joints.

 
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STAGE VIII :: Arm Pistons Concept

Now that I've got almost all of the parts in one assembly, I'm going to work out a few details for the cables and some other odds and ends that go with the kit.

Click NEXT to continue...

 
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