Overly Intricate Iron Man Project

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Active Member
Hey there, and welcome!

This is the start of what will inevitably be a very long project. About a year and a half ago I realized that I could actually start pursuing a dream I'd had for many years of making an Iron Man suit. In my excitement, I ran out to the store, bought some foam and contact cement, printed out some Pepakura files, and started cutting... only to stop and realize that wasn't what I wanted. I realized in that moment that I didn't want to just look like Iron Man, I wanted to feel like Iron Man. To me, that means having a bunch of mechanisms in my suit and always having a trick up my sleeve.

I also realized that replicating the mechanics/functionality is more important to me than replicating the exterior shapes/paint. As a result, I think I'll end up with a Mk 1.5 looking suit first, then make some final changes and "armor" it after that.

Progress has been slower than I'd like, as life has a way of adding new responsibilities to your plate, but I'm happy to share what I have. It's thrilling to work on chasing your dreams, even if it's only a small step at a time.

Table of Update Content:
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Active Member
My second, curved prototype:






What it got right:
  • Captive nuts. The nuts fit exactly like I wanted to!
  • Recessed screws. These fit absolutely perfectly, you don't feel the screws against your skin at all.
  • Latch. The latch holds everything snug, and I don't feel worried about it breaking off. If anything, my worry is what to do if the mechanism to open the latch fails!
  • Hinge. This design is super nice, and a lot sturdier than I thought it would be for how thin the parts are. I might need to improve it a little bit more, to give the armor shell even more space, but for now I'm pretty happy with it.

While this guy is hands down an improvement over the previous version, it's still not good enough for me.

Improvements to make:
  • Uniform rocket platforms. This is one thing the previous version did right. Having all the rocket platforms be the same will make repairs infinitely easier.
  • Better thread slots. It's a bit of a bummer that I wasn't really able to test how I intend to operate the latches. Making the slots bigger should help.
  • Main Rocket platform. I have been planning since the beginning on being able to re-create Iron Man's entrance in Avengers 1, and that involves having forearms that can support a main rocket as well as the mini rockets. I'm positive my insistence on this is what will make my forearms deviate from the Mk 4/Mk 6, no matter how small and slim I make the main rocket, but I'm going for functionality over replicating a specific suit.
  • Better Wrist Connector. I haven't tried using it on this version, but the ring that the wrist connects to has a radius of 41.7mm... and that bugs me. At the time I was just trying to make it as small as possible, but I think I'll want a nice even number that is easier to work with for the next version.
  • Shell mounts. Right now there's no way to mount a shell over top of this. Part of that is due to simply not knowing how I wanted to approach that, and which way would be most maintainable.
  • Elbow hinge mounts. The elbows are going to be a surprisingly big deal, since I'm going to hide some of my bulky electronics in there. As such, if I want my next version to be able to operate servos I need elbow hinges, and if I want elbow hinges I'll need a way to mount them.

I'll probably end up ditching the super curved design for something easier to print/maintain, but it was good to attempt it and see how it worked.


Active Member
As far as the shell mounts go you could use a male/female magnetic plug system like on Xrobots MK VI suit. That's how I intend to design mine once I make it past the Mark 1.5 stage. I'll subscribe as I am excited to see what else you come up with.


Active Member
As far as the shell mounts go you could use a male/female magnetic plug system like on Xrobots MK VI suit. That's how I intend to design mine once I make it past the Mark 1.5 stage. I'll subscribe as I am excited to see what else you come up with.

My hesitancy with using magnets to keep it in place is I'm hoping to use HAL Effect Sensors in my fingertips to control the suit. These sensors basically detect magnetic fields. I'm planning on having magnets in my thumbs to trigger the sensors, but I'd rather avoid situations where the sensors could be tripped accidentally by being too close to other parts of the suit. I believe from my early tests (Summer/Fall 2018) that the HAL Effect Sensors only react to either the North or the South end of a magnet, so it's possible that by being super careful when placing the magnets I could make an arrangement I can't accidentally trigger, but I'd rather hold that as a last resort option.

Thanks for the sub! It's going to be a slow rolling process, but I think I've got a few ideas for the suit that are pretty unique.

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Sr Member
Can a solenoid be used for the latch closure?
I'm using that for my boot mechanism.
I too intend to subscribe...


Active Member
Ah I see what you mean, and I never really thought about that causing a problem with sensors. I'll be sure to keep that in mind once I get that far. I think it could still work, but like you said they would need to be strategically placed so they don't interfere.


Active Member
Can a solenoid be used for the latch closure?
I'm using that for my boot mechanism.
I too intend to subscribe...

I originally considered solenoids, but I decided against it in this case for a few reasons.

The first trouble is Size. Each ring on my arm is 10mm wide, and the gap between the panels (where the rockets and servos will) go tapers down from 15mm to 8mm as you get closer to the wrist. It's hard for me to imagine a solenoid out there with push-pull functionality built in that can fit in that space and has the travel to get a good grip on the parts it's suppose to be latching together. I'd also need consider one for the wrist, which might be an even smaller space to fit a solenoid.

The second problem is one of "how will it fail?". If I lose power to my suit (either a dead battery or because of a short in the wiring, or the Arduino dies, or I mess up my code) I don't want to be trapped in it until someone else can pry me out. If I used solenoids in my arm, I'd either be locked in my suit or the solenoids would constantly draw power to keep the suit closed, and my suit would spring open on it's own upon losing power. I'm attempting to strike a middle ground solution by having threads/cables open the latches, then running those cables to a servo and continue the cable to a loop under the pauldron that I can pull as a no-power emergency release.

If the second problem sounds like I'm overthinking it, well, now you know why I'm calling this project "Overly Intricate" :)
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Active Member
Not a mini rocket.jpg

"...That's no mini rocket."

A slight tease of something else I'm trying to fit into my arm. For those of you unfamiliar with Fusion 360, all the blue markings represent various places where things move.

I'm more or less happy with the shape of everything except the rocket itself. The rocket should have some front fins (I think they're called "canards") to look more like the movie, but I think I'd have to cut into the already thin housing to have space for them to actually look good. Another idea I played around with on paper was having the nose of the rocket unscrew from the body and putting spring loaded fins in the nose. I might give the spring loaded idea more thought at a later date.

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Active Member
Too long without an update of any kind, so I'm going to just try to get what I've been working on written out here for now and maybe video later. (Writing this will help me format my thoughts for any video anyway)

My last update I showed off a very curvy forearm design. I decided that would be too hard to produce and maintain, so I went back to the drawing board to make to something more symmetrical. Here's that design:



As you can imagine, I was pretty excited about this! I had a lot of the motion figured out, from the rockets movement to the arm opening up (I'd be able to make a shield like the Mk 3 with it, as well as getting in and out)...

... but there was a catch. A few catches actually.
  • I didn't (and probably still don't) have proper modeling techniques for Fusion 360, and despite my best efforts to parametrically design everything there was a lot that would just up and break when I changed a dimension.
  • I had designed some things (the mini rockets) incredibly poorly, such that there was no way they were going to be able to be built or work.
  • I was running out of space in my design. I'd thought out all the various parts, just not how they'd intersect and interact with each other.
    • From my white prototypes you might remember that the breakthrough for the latch was having it hinge directly on the shell. When it came time to model that, I realized that it was going to basically cut off the screw I was using to mount the rocket.
    • The mounting holes for the elbow cut into the space I needed for the latches
    • There wasn't any space left for new bolts to connect the shell to the frame
    • Probably more I'm forgetting about or didn't get to yet
  • The whole thing was feeling a bit chunky (37mm from my arm to the top), and there was no way the bulge at the top for the main rocket was going to be hidden in a Mk 4/6 style arm.
  • ...I designed it too big to be printed on my 3D printer...:oops:
    • Remember the old a^2 + b^2 = c^2 ? Well, to maximize the size of parts I could print, I was printing diagonally. I just forgot that if you make the diameter of a circle equal to the diagonal of your build plate then you don't have room to print the circle.

It's fine that this design didn't work out, it's a learning experience. What I'm more upset with in hindsight is that I was so worried about creating a good YouTube video that I didn't stop to document this all at the time. I've given up on enough projects to realize that I might not ever finish a full suit, but I at least want to document what I try, what works, and what doesn't so anyone coming along can learn from it and do better than me.

Sometime in January or February, before I realized the updated design wasn't going to work, I decided to do a basic electronics test on my old cylinder frame. It wasn't anything special, an Arduino, a 16 channel PWM controller, and the servos I already had mounted in that frame. The big thing I learned was that you need to use thin solder if you want to solder small things. No brainer in hindsight, but was having a lot of trouble connecting the header pins on my Arduino before that.

Mid March life got turned upside down, and what use to be normal became impossible... thanks to the addition of a brand new baby in my family!!! :D The combination of an infant, a toddler, and working from home has messed with my schedule for working on my suit, since most of my design work up to now has been done while I've been commuting on the bus. No more bus trips = no more dedicated Iron Man time. I've been having a hard time making a regular schedule to replace that time. Definitely better off than we could be, it's just I'm not one of those people who found themselves with extra free time as a result of Covid-19.

On April 14th I decide start a new file and to take a different approach to this forearm. Being rather dismayed with the prospect of making my previous design look beautiful after the fact, I decided that rather than build from the inside out (like I'd done for everything else) I'd take the opposite approach. So I started with a more elegant/beautiful outer shell and build the inside to fit that.

To help make everything thinner, I decided to purchase some 3.7g servos and see how they compare to the 9g servos I was using. I also picked up a 5 pack of "Longruner Mini Nano" Arduinos (going to need at least one in each forearm, one for the helmet, possibly one to coordinate the other three), and some servo cable extenders (I knew before my basic electronics test that I would want some). I also ordered myself a birthday present - a new 3D printer, the Artillery Sidewinder X1. I got it on sale at Gearbest for $380, and I am loving it so far.


I could literally print a 1:1 copy of my old printer in one go. The print volume is 300x300x400mm, compared to the 120x120x120mm I had before. It's also quieter, heats up faster, has filament run out detection, has assisted bed leveling, is a direct drive extruder... The only drawback is how much space it takes up, lol. I still need to fine-tune it (assisted bed leveling is awesome, but it's still hard to get a good level, horizontal expansion is close but not quite right, and I haven't even touched most of the other settings), but it's nice to finally have a machine that will be able to print as large as I want.

About that redesign? It was rendering pretty nice! I had a nice curve going, I had the shell connecting to the inner frame, and I had the hinge working.

Emphasis on "had". I was so excited to print something with the printer that I printed the frame, and THEN I noticed it was huge near my elbow! I re-measured everything. That part of my arm is maybe 85mm in diameter, the earlier scrapped version I'd given myself a bit of wiggle room and made it 100mm, and when I'd started the newest version I'd given myself some wiggle room again and made it 110mm. Woops! Resizing broke the functionality of the hinges, and definitely flattened the shape a lot. I also realized that because my hinge opens at an angle there was going to be some rubbing against the bracer part. Not quite sure how bad it would have been, whether it would just help hold the arm closed or if it would prevent it from opening, but it is something I'm going to have to be aware of in the future.


During the trial-and-error for this hinge design I learned something super important. When the hinge in the pin-slot is moving straight towards the hinge pin the two sides move straight away from each other, with no rotation! It's as the pin-slot deviates from that where you get rotation. This means that the best way to design these kinds of hinges is to actually design the holes first, and use those wholes to make the linkages. Also, Fusion 360 can't really handle an arbitrary pin-slot shape, so it's likely that future refinements will have to be tested by printing them out. Having this understanding of what to change to effect which property of the hinge is a nice step in the right direction though.

While this red design is certainly more pleasing to look at than the old design I scrapped, I think I'm going to have to put it on ice, possibly scrap it all together. I can't proceed without knowing if the 3.7g servos can lift the rockets like I want (because the servos determine how much interior space I need) and I really like the look of the Mk 6 forearms.

I did have some minor "Eureka!" moments. One I might apply to the next iteration, and it's an idea that would allow more people to use what I design. That would be to make the hinge it's own separate file, make the shell it's own separate file, and then join the two parts together with something like MeshMixer. If someone has a bigger arm, they can scale the shell while keeping the hinge at the proper dimensions. If they want to use a different shell, they could use the same technique to add the hinge to it. I would probably do the same things with the rockets too, although it gets harder to do that with the flaps that cover them. The other idea was to recycle old Micro USB cables and use them to connect my Arduinos to anything that uses I2C (such as the servo controller). The idea is a natural fit because both my electronics and USB are designed for 5v DC, and both use 4 wires (+5v, ground, data 1, data 2), USB cables are already compact and you can get prettier variations (like braided), and I already have them, so I can quickly use them.

Anyway, that's my update. I'm currently at "man who has everything (hardware) and nothing (design)" stage, so when I can remedy the design part I'll be able to get cracking on it.


Active Member
Nice Update!! Keep up the good work, best part of this hobby is the R&D that goes into it!. Also wanted to point out in your video you said you were fairly new to Fusion 360. I follow a YouTube Channel called I Like to Make Stuff and his team put together a training course that covers just about every aspect of the program. I am fairly new to Fusion as well and will definitely be investing in that course to up my skills. The modeling work you have done is very nice so maybe you are already beyond some of the course, but I figured I'd share resources since that is what keeps the projects going!

Again keep up the great work!


Master Member
I just started F360 a few days ago (maybe a week+)..

I really like this series:

Although.. it is for BEGINNERS... he has other playlists that cover more advanced stuff..

I looked for: " I Like to Make Stuff ".. but I didnt see any Fusion360 related videos? (maybe I had the wrong channel?)

Edit: I see now..

its not a FREE thing.. and its located here:


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Active Member
I should clarify - I think I've got a pretty solid grasp of the tools in Fusion 360, and a decent grasp of 3D modeling in general. I can design 98% of what I want to just fine. Of the 2% problem area, some of that is not constraining something the way I thought I constrained it (accidentally connecting to a grid instead of a projected sketch for example), and the rest is just not knowing the order of operations that will make the design the most maintainable or working through the design as I see it take shape. Those aren't the kinds of things that can be taught, they have to be learned through experience - and I haven't put enough time in to get that experience.

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