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“ Damn!!! This was a big project... ”

Tom Gray about building the endoskeleton arm

Building a garagekit 1:1 Endoskeleton Arm FanProject

Building a garagekit 1:1 Endoskeleton Arm

By: Tom Gray
Info: Original tutorial (popup)

Main info

Seeking indepth info on how to model a garagekit 1:1 Endoskeleton arm, TerminatorFiles searched and scrubbed the far edges of the web and finally came accross the wonderful website of Tom Gray.

Tom is a modeller who has always had a special interest in the Aliens depicted weaponry, especially the so called M41A Pulse Rifle. He's even build a website around it which offers information and links for those individuals interested in building and learning more about the prop. M41A, right? Thats cool! But this is a Terminator website, right?

Luckly for us he also has an indepth tutorial on how to build the formentioned Endo garagemodel. And we mean IN DEPTH! After contacting him, he was very happy to share all his info through a seperate TerminatorFiles FanProject; 135 images and detailed references helping you to develop this great prop, from treating its surfaces, gluing together parts to custom modelling and added extra features. Best of all... this detailed tutorial will once and for all delete any reference to any of the flaws one can see in lots of the official props out there; the original Icons prop and even the Sideshow Collectibles props.

Soo... lets get to it! In collaboration with Tom, we've copied his entire tutorial and reproduced it here on TerminatorFiles for all the fans to enjoy, use and persue their own perfectly modelled endoskeleton arms. The tutorial concists of several stages of development, of which the last is, well... still under development; chroming a collectible is not included.

TerminatorFiles owns two of these kits and is going to run through this (and other) tutorials as soon as possible. Whenever we (or Tom) come to the chroming bit, we'll be sure to add it to this tutorial or launch a seperate one in the main FanProject page.

All images have been rescaled to fascilitate a faster loading page (still somewhat big). Click a specific thumbnail for a full view of Tom's original images.

Special thanks go out to Tom Gray, without whom this entire tutorial would never even excist. Thanx for letting us copy it onto the TerminatorFiles portal and for all your continued support on this and other projects!

Stages of development

Stage 1: Cleanup of fingers

Step 1 of 18:
I'll start with the cleanup of excess material also known as flashing. Arrows indicate some flashing between the bushings of the finger rods.

Step 2 of 18:
Arrows indicate where excess flashing was removed. There are several 1/8" rotary tool bits available that will make this job a snap.

Step 3 of 18:
A little more excess flashing on another finger.

Step 4 of 18:
Here again, I utilized several 1/8" rotary tool bits to make this job a snap.

Step 5 of 18:
A 'before' shot of the wrist piece on the 'hand' side. I want to clean this area up a little and define the screw heads a little more.
(After shot: see step 13...)

Step 6 of 18:
Another 'before' picture of the wrist piece on the 'arm' side. I will remove some of this excess material as well.
(After shot: see step 15...)

Step 7 of 18:
First, I polished off the excess resin. Since there will be some rods and cables inserted through this section, I went ahead and drilled out all of the holes necessary to make an easy fit for these later. Notice a few remaining bubble marks and pits.

Step 8 of 18:
Bubble marks and pits filled in with contour putty. There are several types of filler avaiable. I've always preferred the mixture of super glue and talcum powder. I will let this harden and polish this off one more time.

Step 9 of 18:
Arrows indicate bubble pits in a knuckle.
(After shot: see step 17...)

Step 10 of 18:
Once again, contour putty will take care of this. I'll let it harden and come back to it later.

Step 11 of 18:
Arrow indicates another minor bubble pit.
(After shot: see step 16...)

Step 12 of 18:
Contour putty in place. Here again, I shall let this harden and come back to it later to polish it off.

Step 13 of 18:
Tip of the day! Lock down wrist piece so that you have both hands free to dress up screw head detail and other components on the palm.

Here, I had driven two 6 x 1 Drywall screws through existing holes on the palm into my workbench. There is a fluffy towel between the two surfaces to help minimize any stress on the part.
(Before shot: see step 5...)

Step 14 of 18:
Hard to get to seams between 'bones'. Simply use the shoeshine technique!

Here again, the mounting screws holding the piece to the bench comes in handy. Simply run the sandpaper sided to side to remove any remaining seam marks here.

Step 15 of 18:
After shot of wrist piece with a nice glassy surface. Here again, I used a special recipe of Super Glue and Talcum powder. It falls in the small pits, hardens quick, and polishes up nicely.
(Before shot: see step 6...)

Step 16 of 18:
After shot of knuckle pictured above. This will cover nicely.
(Before shot: see step 11...)

Step 17 of 18:
Another after shot, another knuckle... don't let the darker marks fool ya. It's pretty smooth and will cover nicely as well.
(Before shot: see step 9...)

Step 18 of 18:
Fingers in place. Note: I've numbered the tips of the fingers prior to attaching them. This helps to prevent a disastrous mix up when working with epoxy. One neat thing about the kit itself is that the knuckle ends of the hand are already numbered for you.

Stage 2: Thumb prep & gluing

Step 1 of 8:
This stud is where the thumb part is attached. Note there will be a cable attached to this area from beneath the wrist plate. Drill a small pilot hole here for alignment of the cable later.

Step 2 of 8:
The base of the thumb must be drilled to match the stud on the wrist plate. Simply use a strait edge and draw lines connecting the opposing corners of the part. X marks the spot for a small pilot hole.

Step 3 of 8:
Using the pilot hole as a guide, drill out the hole using a 1/4" bit about 1/4" deep. I then resurfaced the area with a block sander for a nice flat fit.
(After shot: see step 8...)

Step 4 of 8:
Some tools for gluing resin: 4" lollipop sticks, 2 1/2" mini craft sticks, mixing board (found at any auto body supply store), permatex 5 min. general purpose epoxy and a ventilated area...

Step 5 of 8:
Thoroughly mix up the epoxy using one of the craft sticks.

Step 6 of 8:
Set the stick in a side portion of the mix. Use the lollipop stick to collect a small amount of glue to be delivered to the parts being attached.

Step 7 of 8:
The people at Permatex aren't kidding when they call this 5 minute epoxy. When the part you are attaching sets, you come back to your mixture only to find that it must be pulled off of the nonstick mixing board. The mini craft stick makes an excellent pull handle here.

Note: You may also wait for the epoxy to harden and simply bend the board. The glue will pop right off.

Step 8 of 8:
The chassis for the hand is near completion and is taking shape to what will soon be a fine prop.
(Before shot: see step 3...)

Stage 3: Pneumatics & palm pistons

Step 1 of 13:
Here are the parts that we will be dealing with aside from the thumb pneumatic. There will be a little clean up prior to attaching them.

Step 2 of 13:
Note: The arrow on the left indicates some flashing that must be cleaned out for a nice fit over the flange on the right.
(After shot: see step 5...)

Step 3 of 13:
A 23mm x 1mm grinding disc in a rotary tool makes this job a snap. 8000 rpm setting does nicely.

SAFETY TIP: Always remember to wear eye protection when working with these tools.

Step 4 of 13:
Arrows indicate some detail that I will clean up and define later.
(After shot: see step 4, stage 4...)

Step 5 of 13:
An assortment of rotary tools and sandpapers was utilized here to shape these pieces up. Some minor filling may be necessary here as well.
(Before shot: see step 2...)

Step 6 of 13:
Arrows indicate part numbers that coincide with the finger and knuckle part numbers.

Note part number 2, near the arrow has a little contour flaw. This part will be covered in the next few steps.
(After shot: see step 9...)

Step 7 of 13:
I wrapped a guide of masking tape first. This will help to mold the filler.

Arrow indicates where the filler will be placed.

Step 8 of 13:
Arrow indicates were filler is inserted and shaped even with the masking tape. Here again, it's a special mixture of Superglue and talcum powder. Gently sand even and then score a break between the filler and the masking tape.

Step 9 of 13:
The tape will gently peel right off and leave a nice sharp contour.
(Before shot: see step 6...)

Step 10 of 13:
There's still some minor cleanup needed for these parts. Before I go any further with them, I thought it would be a good idea to do a preliminary test fit.

The hand is taking shape!!

Step 11 of 13:
Here, I decided only to epoxy the upper connections first. Gluing both ends at the same time can be kind of risky and messy. Well... for me it could be anyway.

Note: Wooden dowels keeping the lower joints centered with the hole.

Step 12 of 13:
Here, I've got 8/32 x 3 1/16" Zinc treated set screws. Thanks to Paul for sharing a little inside secret with me about this prop. :)

Arrows indicate placement for these screws.

Note: This step is not absolutely necessary for an attractive display piece.

Step 13 of 13:
These parts will only serve to strengthen this lower joint and provide a little inside detail in the hand. I'm going to epoxy these in place and get started with the palm pistons for the next update.

Arrows indicate placement for these screws.

Stage 4: Palm pistons & linkages

Step 1 of 12:
Arrows indicate 'the bits where the small pistons join to the fingers'.

Note: A little bit of surface has been lost somewhere in the casting process. Behold! Some of the fun and challenge of the kit!
(After shot: see step 3...)

Step 2 of 12:
I decided to rob some 'limbs' off of a parts tree from another model kit. These are some cut pieces. Dome the ends of each piece and then cut a flat surface using the bit shown in the top center of the picture. Here, I made the decision to drill and bore a small hole to suggest placement for a hing pin.

Note: Phantachrome is a semi-transparent finish. So, if you do these steps, be sure to use materials of a light or neutral color.

Step 3 of 12:
Here, I've cut the ends of those parts I made in the previous image and have attached them in their respective places.

Note: The piece on the far right of the image is a total replacement. To do this, you simply flatten the nub that is there and bore a small hole no more than 1/4" deep at the same angle. Cut the part you make, to the right length and epoxy it in place. This makes for a pretty durable pivot point.
(Before shot: see step 1...)

Step 4 of 12:
Arrows indicate where I've dressed out some detail of the palm pistons. See the before shot for reference if needed.
(Before shot: see step 4, stage 3...)

Step 5 of 12:
Note: Each palm piston is already numbered in harmony with finger and knuckle pieces. This detail comes standard and you will find extremely helpful.

Arrows indicate where I've added a little extension to the palm pistons using surplus from that same parts tree used earlier in this tutorial.

Step 6 of 12:
Arrows indicate the attachment of the first and second palm piston.

Note: If you are thinking of making these rods out of aluminum, I would recommend using 1/8" tube. Cut the piece to length and simply smash the end where it is supposed to flatten. After that, grind a nice curve in the end and drill the hole for the hinge pin.

Step 7 of 12:
Arrows indicate all four attachments of palm pistons.

Note: I've installed that same type of set screw, as I mentioned earlier, right below each knuckle, for a little extra detail.

Step 8 of 12:
Base shot of all four palm pistons. Arrows indicate the area where the number I and I'v palm pistons extensions meet the wrist plate.

Step 9 of 12:
Another view of the palm piston attachment. Arrow indicates the base of the number I palm piston.

Step 10 of 12:
Shot of thumb piston. (i.e. palm piston Part 5) Arrow indicates where I've attached another extension.

As with the others, this only adds to the strength of that particular connection.

Step 11 of 12:
A very grainy view showing the thumb piston attached. Sorry, I try to stretch my digital cam to its limits :). Arrows indicate where the glue is placed and injected.

Step 12 of 12:
The build-up of the hand is now complete!

Stage 5: Arm & cuff

Step 1 of 15:
Here again, I begin with these parts by isolating any surface flaws and bubbles. Arrows indicate two bubbles that are typical to what you could find. For the most part, the casting of the main beam and cuff are very clean.

Step 2 of 15:
Here, the bubbles are filled and the area around this wrist joint is resurfaced.

Step 3 of 15:
In this picture, the red arrow indicates detail of the ball joint that makes up part of the wrist. If I'm not mistaken this groove would allow for side to side movement (articulated arm) along the pin beneath it.

Step 4 of 15:
The other side of that same section. It's a little filled in right now. I will clean this part out to match the opposite side.

Step 5 of 15:
The other side of that same section. It's a little filled in right now. I will clean this part out to match the opposite side.

Step 6 of 15:
After shot of this part. Arrow indicates where the excess resin was removed to suggest the groove. I utilized an assortment of engraving cutters with my rotary tool to make this opening.
(After shot: see step 14...)

Step 7 of 15:
At this point in the assembly, I'm going to check the fit the main beam and the cuff. This picture shows the attachment end of the main beam. The red arrow indicates the threaded hole for the screw that will hold this in place. This part is formed around a steel rod for added strength.

Step 8 of 15:
Initial test fit of the main beam. The red arrow indicates the treaded opening of the main beam and it is pretty far off center. This is a special situation. It is highly unlikely that you would have to do a relocation like this, but my next few steps may prove helpful as it can apply to an array of similar situations with resin kits.

I will need to relocate the hole on the cuff. The first move I make on this is to draw in some cross hairs that zero in on the center of the threaded hole.
(After shot: see step 12...)

Step 9 of 15:
Next, I'm going to smooth out the inside surface of the cuff and apply a piece of masking tape over the backside of that hole. Make sure that the area is sealed off.

Step 10 of 15:
Here, I've filled up the opening with that mixture of super glue and talcum powder I like to use so much. Since there is quite a bit of this in one place, it's a good idea to let it harden over night. Using the cross hairs from an earlier step as a guide, drill a small pilot hole.

Step 11 of 15:
Note that the masking tape will pull free from the filler once it has hardened. The red arrow indicates the new pilot hole that will center the opening.

Step 12 of 15:
Here, I've made a countersink opening for the flat head screw. The center is a 5/16" hole. The outer bevel is hand carved with a 1/2" bit. A similar treatment was applied to the other three arm piston attachment holes.

Here I've done another test fit and alignment check. The red arrow indicates the threaded hole of the main beam.
(Before shot: see step 8...)

Step 13 of 15:
Another shot of the inside of the cuff with the hole completely relocated. The red arrow indicates the filler of the original opening.

Step 14 of 15:
An after shot of base of the cuff. This area is now almost completely resurfaced. Note that I did manage to get that seam to follow the circumference of the cuff ;).

Just a little more polishing up and this will be ready!
(Before shot: see step 6...)

Step 15 of 15:
Final test fit of these parts. Here, I'm going to utilize a 1/4" x 1" Stainless Steel flat head screw to take full advantage of the entire threaded hole of the main beam. The red arrow indicates the tip of this screw when driven all the way in. Once the epoxy is in place, this will help to provide a super strong connection between these parts.

Note: Do not glue these parts yet!

Stage 6: Endo elbow

Step 1 of 19:
The elbow comes as one solid piece. This one has a little resin build-up in some hard to reach places. The red arrow indicates some of this.

Step 2 of 19:
The rear of the elbow. The red arrow indicates some more of this hard to get to excess.

Step 3 of 19:
This view shows the cuff end face down. Before I go any further, I make a note of the location of this recessed screw head. The red arrow indicates this. Also, I've gotten in the habit of making a few reference marks in case they are needed later.

Step 4 of 19:
Using a coping saw, I carefully remove the hubs from the elbow. The red arrow indicates a flat spot that will have to be filled. I will be resurfacing these as well.

Step 5 of 19:
Another angle of those cut pieces. The red arrow indicates placement for a 3/8" vertical hole that I will drill for a work stand.

Step 6 of 19:
This picture shows a few stages of resurfacing. Notice the bevel is a little out of alignment on the inside hub. I will try to correct this later. Also, the red arrows indicate where I cleaned out the attachment for the forward upper arm piston.
(After shot: see step 13...)

Step 7 of 19:
Initial resurfacing is complete on these two pieces. The red arrows indicate where I drill two 1/8" pilot holes centered on the bolt ends. For the sake of accuracy, I utilized a drill press for this.

Step 8 of 19:
Using that same 1/8" bit, I hand scored a center point for the elbow chassis. The lower red arrow indicates where I drilled a 3/8" opening. Once again, I utilized a drill press for this.

Step 9 of 19:
Inside surface of the elbow hubs. Using the 1/8" pilot hole from an earlier step, I used a 1" spade bit to gently score a nice countersink socket for the T-Nuts that will be inserted here. The red arrows indicate these openings.

Left: Hub T-Nut will be glued in face down like suggested in this picture. I used a 7/16" bit to bore out the opening for a nice countersink for this piece of hardware. I also had to grind a little of the end of the T-Nut off so it would fit all of the way in. You can only drill this whole so deep.

Right: Hub T-Nut has to be glued face up as shown. This part includes a 3/8" threaded rod, 1 9/16" long. Actual lengths may vary depending on your initial cuts. There's a socket head on the other side so I only drilled a slight 7/16" countersink here for possible adjustments.

Step 10 of 19:
Before gluing the hardware in place, I filled the original 1/8" pilot hole.

Lightly coat the end of a 3/8" hex wrench with a touch of motor oil. Arrow indicates the wrench. Some people call these Allen Keys. Lock it down to your workbench. I used an 8" C-clamp. Balance the outer hub on the vertical end of the wrench. This will serve as a nice tight plug for the filler to be poured in.

Step 11 of 19:
Gently remove the wrench when the filler hardens. Superglue and Talcum powder is pretty aggressive so you may have to tap the wrench with a small hammer. Be patient here, it will releas. Also, pour in a little dish washing detergent and water afterwords. This will loosen up any residual oils.

Step 12 of 19:
T-Nut and treaded rod are both epoxied in place. Notice the brads inserted here for added strength. I marked a red line around the 'viewable' base of the threaded rod just in case the epoxy fails.

While this hardens, I will work on the other hub.

Step 13 of 19:
In this picture, the red line on the left indicates about a 7 degree beveled edge of this part. The line on the right indicates almost no bevel. To fix this, I set the platform of my sander to 7 degrees and carefully turn the part until the bevel is uniform all the way around. If you do this step, pay close attention to the sound of the sander against the part. It's a good indicator to the completion of the new bevel.
(Before shot: see step 6...)

Step 14 of 19:
Right side of elbow chassis. The red arrow indicates where I've followed my 1/8" pilot hole from an earlier step and bored a 7/16" hole about halfway through.

Step 15 of 19:
Left side of elbow chassis. I followed the original 1/8" pilot hole with a 3/4" spade bit just far enough to almost completely recess the Nylon Spacer. Once epoxied in place, this will offer a little cushion for the metal to tighten up against. The red arrow indicates the nylon spacer in place. Any remaining inside diameter of this hole is 3/8".

Step 16 of 19:
Here, I've inserted the right side hub in place and threaded on the left hub's T-Nut to a snug fit. Arrow indicates where I've made a reference mark at about 11:00 O'Clock. I've digitally enhanced this mark because it's kind of hard to see.

Step 17 of 19:
Here, I've marked the line around to the other side of the T-Nut. I've aligned it with the red line on the hub itself. This line represents the location of that set screw, on the outside of the hub, seen in the third picture of this update.

Grind off three brads, as with the other hub, to about 1/4" to 1/2" in length and epoxy them in place for a little added strength. Note: Store bought hardware is not perfect either so mark and drill shallow pilot holes for these as well.

Step 18 of 19:
Here, I've test fit the part. Snug it up and the set screw will land on the 11 O'Clock position!!!

Step 19 of 19:
There's a little clean up and fill remaining for these parts but, when the dust settles, this is what you should have.

I've not attached the cuff yet, but I will be covering this in Stage 7 of this tutorial.

Stage 7: Elbow to cuff concept

Step 1 of 7:
You can see the inside of the cuff in the lower left of this photo. I am going to engineer some hardware that will attach to the center hole of this piece without modifying it any further. First, I'm going to countersink another T-Nut to be glued in, a little later, to the elbow chassis. The red arrow indicates the location of this piece.

Step 2 of 7:
A little brainstorming, and a little shopping around,... a whole lot of funny and confused looks from sales clerks at several stores, and this is what I came up with. WIPER MOTOR BUSHINGS, found at most Autozones in the 'HELP!' section.

Step 3 of 7:
I pulled out the metal grommet, and screwed in a 3/8" threaded rod. This serves as an excellent handle as you grind away a little of the lower diameter so it fits snug inside the center hole of the cuff. This material is like car tire rubber compound, so I used my disc sander to do this.

Step 4 of 7:
Here, I've taken that 3/8" threaded rod and threaded on the T-Nut that will be glued on to the elbow. Also, I've threaded on what's left of the wiper motor bushing so that it is flush with the end of the threaded rod. The red arrow indicates where I've put a mark on the threaded rod. This is where it will have to be cut.

Step 5 of 7:
In this case, it's just a little over one inch.

Step 6 of 7:
Here, I've epoxied in both the threaded rod and the T-Nut, in the same manner as one of the elbow hubs, to the top of the elbow. I've left 1/2" threaded rod protruding for the cuff.

This area will need to be cleaned up a bit but I will deal with that later.

Step 7 of 7:
This picture simply shows the concept of this new hardware. Here, I've taken my modified wiper motor bushing and jammed in another T-Nut. This piece, once installed inside the center of the cuff, will allow it to thread on nicely without the use of any tools.

As it gets tighter, it squishes the rubber outward making a very solid bond to the cuff. This is similar to the way a sanding cylinder attaches to a rotary shaft.

Note: Space is not very forgiving inside the cuff. If you do these steps, you will have to modify at least one of the arm pistons. This is covered in Stage 8.

Stage 8: Arm pistons concept

Step 1 of 22:
First, I flattened these nubs and drilled a small pilot hole in place of them.
(After shot: see step 5...)

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

Step 2 of 22:
Next, I will resurface the other ends of these pistons. These are the ends where the aluminum rods are installed.

Step 3 of 22:
Using a circle compass, I found the radius of the piston ends and marked the center for each peice.

Step 4 of 22:
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.

Step 5 of 22:
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.
(Before shot: see step 1...)

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

Step 6 of 22:
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.

Step 7 of 22:
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!

Step 8 of 22:
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.

Step 9 of 22:
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.

Step 10 of 22:
Thread the cuff to the elbow. This makes the perfect, upright stand for you.

Now, epoxy the hand in to place.

Step 11 of 22:
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.

Step 12 of 22:
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.

Step 13 of 22:
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.

Step 14 of 22:
Epoxy these parts in place like shown. Each piece should line up with the screws heads on the top of the wrist plate.

Step 15 of 22:
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.

Step 16 of 22:
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.

Step 17 of 22:
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.

Step 18 of 22:
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.

Step 19 of 22:
Final stage of this assembly is a snap...

Step 20 of 22:

Step 21 of 22:

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

Step 22 of 22:
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.

Stage 9: Connecting cables

Step 1 of 15:
This stage will cover how I attached the connecting cables in the assembled arm. In the lower right portion of the image there is a gray resin piece. I will be replacing that piece with a scratch built equivalent.

Step 2 of 15:
After sizing up details on the screen used endo arm, I soon noticed that ten to fourteen feet of cable will be needed to finish off this arm. The endo arm kit for this tutorial was missing the cables so I set off to find the closest match to it.

It is exactly 1/8 inch O.D. and hollow spring cable.

From what I understand about it is that this is commonly used with puppets and animatronic (sp) items.

Step 3 of 15:
Thanks to the most helpful advise from fellow modelers, I found a speedometer cable repair kit at a local auto parts store for about $8.00.

Step 4 of 15:
In comparison it is pretty close. Foreground cable is the substitute speedometer cable. The background cable is the original part to the other endo arm kit.

Step 5 of 15:
I cut four pieces at 12 inches in length. These will be run through the palm plate and into the base joint of each knuckle.

Step 6 of 15:
Here, the red arrows indicate where the openings for the cables are to be installed. The bottom red arrow shows the area for the thumb cable. This piece is one of five additional cables cut to 9 inches in length.

Step 7 of 15:
To attach the base of the cables to the cuff, I used a stack of four heavy duty magnets. Something like this can be picked up at any good hardware store for under two bucks. The magnets will cling to the steel hardware created in Stage 7 of this tutorial.

The red arrow indicates placement for the braided hose covered next.
(For top connection: see step 11...)

Step 8 of 15:
From left to right: 3/8" copper tubing, resin part from kit, 1/4" copper ice maker line, Calterm # 73520 Expandable Sleeving. These are some of the main pieces used to fabricate an adjustable braided line.

Step 9 of 15:
...and a comparison photo for the new, nicely curved part.

For the end piece, I used a 10/24 hex nut and a cut piece from a steel tent stake. This is epoxied in place and the copper cuffs are crimped to hold the braided sleeve in place.

Step 10 of 15:
In the side of one arm piston, I've secured one additional magnet.

There is more info about this type of magnet in Stage 8 of this tutorial.

Step 11 of 15:
Given the amount of steel that is making up the end of my custom cabel, it makes for a very strong connection.
(For base placement: see step 7...)

Step 12 of 15:
One very important detail for this replica, the arm piston linkage. The screen used endo arm includes this piece, broken in the same radius as the upper arm chassis. This part was missing on two of the kits that I have been working on.

Step 13 of 15:
Thanks to the helpful custom machining of russrep, I now have the part needed to complete this arm and tutorial :)

For more info on this part and any additional custom machining, I encourage anyone to contact Russ first. (Ed. Note: All e-mail addresses have been deleted from this tutorial. Check Tom's original tutorial for info!)

Step 14 of 15:
Here, I've utilized an engraving bit to make the broken end appear pitted like the other broken arm piece.

Step 15 of 15:
This piece attaches with a 1/4" x 1" set screw and moves freely inside the well. The arm is now ready for the triple chrome plate finish.

Completed views

Before sending this endo arm on its way, it is time to take a step back from it, zoom out, and snap a few shots of the assembled piece.

There were at least two versions of this arm used in T2. This arm is modeled after the one to appear first in the film.

The major differences can be found with the elbow. This one has the anatomically correct version as if it were pulled directly from a complete endo.

The other commonly known display endo arms have the left elbow. This would be consistent with the version of the film prop that was smashed into the floor by John Connor.

In total, it is about 23 inches tall and 5.5 inches at its widest area.

The additional cables really do make a visual difference with this piece.

Special credits

A special thanks to necronom for his incite and encouragement throughout this entire project. He had a very special influence with regards to this shot in particular. It is one of my favorites. Be sure to check out his web site, The Colony, for more information on the endo arm as well as quite a few other ALIENS and TERMINATOR related props.

A special thanks to Rich for helping me locate a nice match for the endo cables :)

A special thank you to SFPROPS for providing excellent reference material on this broken arm linkage...

...and a very special thank you to russrep for his most excellent custom machining. For more information on this part and any custom work that you may require, email him directly. (Ed. Note: All e-mail addresses have been deleted from this tutorial. Check Tom's original tutorial for info!)

A list of very helpful people...
The Mantis, PHArchivist, RockBottom, QuartZ, darthscifi, swpropmaker, BrundelFly, Jack Knight1979, Jedirick, propcollector, westies 14, kleine Stefan, necronom, kurtyboy, SFPROPS, Terminator Crazy, p0sitr0nic, Sidewinder, robstyle, SgtFang, vader1974, Holy Zoo, exoray, thedap, O. F. Gunner, rein one, kre8-fx, etheren, DARTH SABER, itbedave, rayra, Lawgiver, eltee, Darth Phaeton and russrep.

Damn!!! This was a big project...

Related info

Check out the following internal and external links for more info about this FanProject.

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Page last modified: April 14, 2012 | 12:29:35