LEGO Skeleton MegaFig

30 years ago, LEGO released the first skeleton minifigure. Since the initial release, they have populated over 180 different LEGO sets. This was always one of my favorite minifigs and last year right before Halloween I found one 3D printed that was 10x the original. I had to have it for, you know, research. I thought what if I could build him to be 100X the original? I attached the photo I sent my wife when I got the idea. And of course there is a nerf dart in the photo. I swear they multiply.

I decided I definitely wanted to build a larger than life version and I set out to sort the details. I mean seriously, how do I build one? What should I make it out of? How does it not crush under it's own weight? And honestly, how big is 100X an original mini fig? So many questions... Hopefully I can answer them all in this detail and pic heavy Instructable.

****Tools****

Permanent Marker - I like the Inkzall from Milwaukee but any will do.

Tape measure and maybe a square or T square or drywall square.

Hot wire cutter. I made my own and bought one from Hotwire Foam Factory

Hot wire shapers / Bow - Hot wire foam factory sells a nice set of assorted tools found Here

GreatStuff Pro Sprayfoam gun Amazon Link

Curry Comb Amazon Link

Sand paper - I used sanding blocks, loose sand paper, and a random orbital sander

Disposable paint brushes - I used 2" disposable chip brushes Amazon Link

Drill with squirrel mixer

Skewers - I used some stainless and bamboo to hold the foam when gluing.

Metal band saw - To cut the Unistrut to length - I borrowed one from a neighbor

Metal File - To deburr the metal once cut - no more sharp edges

Lazy Susan base - I used a 12" one from Amazon to help turn the foam when cutting Amazon Link

Adjustable wrench or sockets- To tighten the bolts on the unistrut.

Mixing and measuring buckets - I bought super cheap disposable ones from Menards

****Supplies****

Styrofoam - I used EPS compression foam found on Facebook Marketplace

Great Stuff spray foam Home Depot Link

Spray Foam Cleaner Home Depot Link

Plastic wood filler - DAP Plastic Wood Amazon Link

Rubber Roof Coating - I used Henry Roof Guard from Home Depot

Styroplast Hard Coat - I used 5 gallons Hotwire Foam Factory Link

Dynaflex - White Caulk I had laying around from another project. Used to fills some gaps at joints

Unistrut - Found used on Facebook Marketplace

Dual monitor computer stand - Repurposed for shoulder joints from a thrifted old stand

PVC pipe / 5 way fittings - Used for shoulder joints

Paint - I used spray paint, acrylic enamel, and some industrial coating that was out of spec and being thrown away at my work called macropoxy.

J hooks - Rebar stakes to secure the structure outdoors. 24 and 16 inch. Amazon Link

****Safety****

Safety glasses

Respirator for fumes / dust

Gloves - Nitrile

Closed toe shoes, well sometimes crocs. I mean I do wear them a lot.

Clothes you can throw away - the styroplast will destroy whatever you wear.

I thought there was just one LEGO skeleton model. Man was I wrong.

These are the main 3 types in most sets. The one I remembered was the original Floppy arm skeleton which has been around the longest, 22 years, but has since retired since 2017.There is also a droid arm version and there is a bent elbow version. Within these 3, the whole skeleton other than the arms and shoulder joints are exactly same.

But....

There is also a Minecraft skeleton, a Minecraft Wither skeleton, A specialty army General skeleton (Actually 4 different Generals), Bionics skeletons, Ninjago skeleton, special black skeleton from Harry Potter... The list keeps going.

I wanted to build the iconic LEGO skeleton that most people remember. So..... I chose the Floppy Arm skeleton, which may honestly be the hardest to create when it comes to the arms or really how the arms attach.

Once I decided on the type or style I was going to build, I had to break down the pieces two ways. First I needed to measure every dimension. I had to sort out how large each piece was, how thick each piece was and multiply it by 100. I borrowed a photo from a 3D printed version of the Floppy Arm Skeleton and used calipers that measured to 1/1000 of an inch on my actual minifigure. This made it easy to multiply by 100 to get my dimensions. So for example. when measuring the thickness of the head, it came out to .400 inches. So you move the decimal over 2 places and you get 40 inches wide. The ribs were .050 inches so 5 inches when 100 times the size. I took tons of dimensions and I still missed a few. I sorted those out later.

When I added it all up, it came out to 13' 5" tall or about 408 cm for all my across the pond friends. Now the issue with this height is that somehow I have to support a head that is 40 inches in diameter and 46" tall, plus a rib cage that is 52 inches wide with arms that are wider than that. The spine? Well the spine comes to the small diameter of just 13". If made out of foam as I had planned, it would crush itself and break apart. So now what? Oh.... a skeleton inside of a skeleton. An Armature which will be made of metal and support the weight. Original intent was to go with some threaded steel pipe. This was rather expensive, must be cut to exact length and threaded, plus it flexes some over long lengths. Not ideal. I stumbled across a listing for Unistrut. Who knows why marketplace advertised it as a listing because I look for workshop tools on marketplace but never steel. But, I was able to buy the Unistrut and a bunch of connectors at a fraction of the price of new as they came out of a building and were used. I didn't care if they were used, it worked great for me.

Now the second way I had to break down the pieces was how would they be broken down individually. I mean where were the breaks where I could bolt the Unistrut together or attach an arm? I sorted it into 8 pieces: 2 arms, 2 Legs, Pelvis, Rib cage, Small section of spine to cover the bolts at the base of the pelvis, and a head.

Once I had the break out of pieces and the Unistrut, I had to sort out how to cut and attach it, not only to itself but to the foam and most importantly find a way to secure it to the ground. I bent the connector pieces to make odd shapes that don't come standard. Most of this was done with a giant metal brake at work with a competent operator, not me. These are 1/4 thick steel. They don't bend easy. I was making a structure for inside a foam skeleton so non standard would be ok for my use. I didn't need it to hold up to structural weight in a building, so bent pieces it was. I had to add points for guy wires to help stabilize the height. I also needed to add base supports to stake down and give the whole structure stability.

I cut the lengths of the Unistrut on a metal band saw I borrowed from a neighbor. I filed down the burrs left from the cuts and painted the ends to keep them from rusting. Although I assembled everything to check for fit, I then took it apart in sections as the foam has to surround it, and to do that, I need separate pieces to thread through the centers of the foam when complete. I basically had 2 leg sections, a Pelvis section, Ribs and arms, and pieces to hold the head steady.

I am sure I will get questions on what I used to cut these. Here is a link to an instructable I did on my custom tools created for this job.

I had blocks of foam that were 4'x8' sheets. Some were 20" thick. Some were 14" thick. There was damage from them being on the construction site and being transported to a storage unit before I got them. I had to lay out the sizes I needed around the damage and cut them out with a hot wire. Originally, I had cut pieces in giant blocks and planned to just work them down into the shapes I needed. I quickly changed course and started cutting them out in smaller pieces I could put back together to make a larger section. An example is the arms needed cylinders that were 19.5 inches and 12.5 inches. I cut them separate which gave me accurate individual pieces and just glued them together when finished. With this adjustment, I was able to get a few extra pieces out of the foam as I had less waste. I also could let the hotwire do most of the foam removal vs me having to hand carve with a curry comb.

I cut down 4 of the giant 4x8 blocks into all the individual pieces. I think there were 32 in total. Each piece was cut as close to final size as I could get before smoothing and sanding. The largest piece was the rib cage at 52" wide. The head pieces were 40" diameter, not small by any means.

Once the blocks were broken down into sizes for the individual pieces, I had to shape them a bit further. Some were cut with specialty shaped hotwire forms. Some were formed by chunking off lots of foam with a Curry Comb. Once the final shapes were achieved, I sanded everything with a manual drywall round sander and 80 grit sand paper. This removed any uneven edges or bumps from the hot wire or curry comb. It smooths the surface for adhesion as well. Every side had to be sanded as some was slightly sun damaged and I had to remove that thin layer so the foam would adhere together.

My go to for attaching foam is great stuff spray foam. I don't like the regular cans you get at the big box stores as the straw always gets clogged up and most of the time I just need a little bit here and there. I use the pro spray foam gun that allows a can of foam to stay attached for months. I can control the amount of foam dispensed and it works amazing for adhesion and filling gaps. You can sand it fairly smooth as well if needed.

When the glue (spray foam) is drying, skewers work great to hold the parts together. I had some stainless steel reusable skewers and some bamboo. Both work well and can be removed after 30 min or so as the foam sets up. Spray foam does want to expand so use just enough to get a thin layer on the foam. More than that and it will push apart the pieces. I also go back and press down to make sure they don't expand out after just a few minutes. The pro foam really does well though at not expanding too much. The regular stuff is a completely different formula and it will expand like crazy.

I made a detailed instructable on the tools I created to cut the foam in this project. I linked it in step 3 but it can be found Here again. The DIY tools were used for 90 percent of this project. It is very hard to find affordable professional tools when cutting somethings as large as I was. I needed 48" tall clearance and at least a 50" throat to the cutting wire. A large table like that is 1000s of dollars. Making use of my table saw as a base for the freehand hotwire scroll saw was the only logical solution as I was able to build it for less than $100.

I did purchased an Industrial hot knife from the Hotwire Foam Factory this year and it was invaluable. I have tried the Harbor Freight version in the past and both of the ones I tried lasted less than 10 min before they burned up the internals. The sled attachment on the pro knife was super helpful. I did modify the blade on the sled to make a custom shape for the spine with some Tig weld wire. It worked really well for my needs.

When I purchased the pro knife and all the coating, the Hotwire Foam Factory asked what I was building and sent me a hotwire tool kit as a bonus to help me finish the project which was awesome. I did use a variety of the tools they sent for different unique applications at the end of the build. I will say the 24" bow is so much easier to use than my DIY solution I had created. I was able to get some very clean cuts from these tools (The yellow handle tools in the photos).

Whether you have DIY tools or Pro tools, the final shaping is almost always done with a curry comb and sand paper. Hot wires get you close. Manual sanding gets it perfect.

Since I picked the Floppy Arm skeleton, I had to sort out how to actually attach the arms. Sure, when they are tiny and plastic a little ball that sticks out works great. But when the arms are over 5 feet tall, the torque would tear apart a simple foam ball joint. I was also worried about the pressure it would put on the rib cage as it was only 5ish inches thick on the sides.

My solution was a dual computer monitor stand. I found a super cheap used one on Facebook and cut it apart. I found a piece of metal square tubing that fit over the arm like a sleeve and had a friend weld it onto a piece of my Unistrut. I did my best guess at the height it needed to be in the rib cage and attached it to the frame. The arms then had a hole drilled down the center using a piece of PVC pipe that was the same size as what I was going to use to attach to the computer arm. I made teeth on the end and twisted it by hand into the foam. The PVC was then glued to the metal with some QUAD OSI caulk which is super sticky and holds to just about anything. It does take 3 days to dry.

I ran into a problem when I attached it to the rib cage. I had left the shoulder joint way too high, like 9 inches too high. I removed the PVC and cut it out further recessing the arm joint near flush now to the base. This adjustment got me to the correct height for the arm attachment. But it was now going to severely limit the movement on the joint. I can still move it up and down but forward and backwards, not so much. Oh well. I guess I can't engineer it was well as I was hoping but it still moves and that works for me.

As much as possible, I want the armature hidden. There are only 2 places where you can see part of the metal. This was left on purpose for anchor or guy lines. One place is at the top of the legs and the other is in the chest for the arm support.

I used the Pro hot knife with a metal U shape to cut out some channels in certain pieces and I used my hotwire cutter built on the table saw to cut the centers of most parts. To get the wire through, I had to drill a 3/4 hole through each piece and feed the wire down. It was a bit tedious but it saved me from having to completely cut each piece in half and reglue them.

You can see some of the pictures where I cut the wrong direction on the rib cage and had to glue the pieces back on. Yeah... that was frustrating but mistakes happen.

I also had to add some PVC sleeves to the bottom of the head. This allowed for the Unistrut to go up inside and keep the head in place without damaging the foam/ head.

Anywhere that the armature was staying in place permanently, I used spray foam to secure it.

Any time you work with foam, there is damage to the surface. It could be your hot wire got too hot and melted it. It could be you scuffed it against something when moving the foam. Or you could have just messed up and cut off too much. This is where a product like Plastic wood comes into play. I wish I could have just got a gallon of it, but they didn't sell it that way so I went through 4 of the 32oz containers. I thin it down with about 1/2 cup of water per container so it goes on thinner and smooth. Once on, you have to let it fully dry and then lightly sand off any surface imperfections. You can pay for the dry dex addition which is pink and shows when fully dry. I saved the extra money on that and just let it dry overnight.

After sanding it smooth, I coated the entire sculpture in a rubber roof coating, which took about 2 full gallons. I did this for 2 reasons. One, it gave a protective coat over the foam because if I missed a spot in the next step on the hard coat, I didn't want the paint to eat into the foam below.

Reason 2 was it helped to smooth and stiffen the foam a but also adhere any dust to the surface so the hard coat would stick and not want to peel off. I don't think I needed it for this reason, but that is why I did it. The hard coat was way sticky and it would not have mattered.

Something to note. Adhesion is key. I trialed the plastic wood, the rubber coating, and a bit of the hard coat in layers to some scrap foam for adhesion testing. Each layer needed to stick to the one below or failure would occur. If you choose to hard coat something similarly to what I am doing on whatever your project is, make sure you test small amounts first for adhesion. I found out that the paint I was hoping to use did not hold on the hard coat once it had cured. So I had to change paints.

In the past, I have used wood glue and sand to hard coat large builds. This works ok for bump resistance but is not a smooth finish. For this build, I wanted a smooth plastic looking finish. I purchased 5 gallons of Styroplast from the Hotwire Foam Factory. The finish is really unique, very much like plastic, but also rather difficult to use on any vertical application. Where I had flat surfaces, it looks amazing. But anything that was curved or vertical dripped and sagged.

Styroplast has to be mixed in the correct ratio. A 1 gallon pack has a bucket with exactly 3 quarts of Part A and a can of 32 oz or 1 qt of part B. I divided this up into 3 buckets for 3 individual quarts at a time and then added the part B and mixed for 2 min with a squirrel mixer. I watched someone do a whole gallon on a video once. I have no idea how you do that much and not waste it. And rewatching the video, they poured it all over the top and it likely dripped more than a quart off. So what I am saying is don't mix more than 1/4 to 1/3rd at a time. It will set up and you will waste a ton.

When they say there is a 20 minute work time, it is exactly that. On my first batch, I mixed 1/2 gallon which was too much. It went from a syrup like spread consistency to cold molasses at exactly 20 min. Once it hits that mark, it is no longer workable with tools. You can sort of spread some of the drips but it continues to sag on vertical surfaces past the point of it being workable any longer.

Now it may be I used too much but I was spreading it on thin with a brush and a card scraper. I don't know that I could have done it any thinner and used the 1/3 gallon batches I was making. I found I needed to set timers. I set a timer for 10 minutes from the moment I added the 2 parts together. I could do detail work here. When the first timer went off, I set a second for another 10 minutes. This second timer was get large areas coated. When the second timer went off, I had less than 2 minutes to get everything out of the bucket and spread out. You then have 5ish minutes to smooth the drips before everything just sticks and makes a mess.

My goal of smooth plastic wasn't happening. I had to sand out all the drips and that took the shiny feel away from the finish. But it was going to be painted so it should be ok.

Something to note here. Part A, the White part, never dries, like ever. I had some on the outside of a mixing bucket and 10 days later, it transferred to my hand when picked up. So whatever you use, you have to plan to toss. I used disposable mixing buckets and also mixed in the containers it came in.

Also, whatever clothing it gets on when mixed, it adheres and sticks. You want to wear long sleeves and gloves. Both are going to be tossed. I had old crocs on and just walking through the drips coated the bottom of them in a thin plastic urethane layer that made them super slick when dried. I am likely tossing the shoes too.

Something else to note. The styroplast has to be painted. One of the pics shows a drip that was in the driveway for a week. The sun darkens the stryoplast a lot. I don't know if the UV will damage it over time but I imagine with the rapid color change that it would.

Drips, sags, oh the horror. A random orbital sander with 80 grit paper took down the drips pretty well. But It also easily sanded too aggressively if there was a thin spot and opened up to the foam again on a corner of my first piece. I had saved a small amount of the styroplast for touch ups and I used it here.

I could not get the surface as smooth as I wanted as I was afraid to take too much off and get into the foam layer, so I just got the major drips off and called it a day. There were a few places I could not get my sander into well and I used a file there to take off the high points.

This was the first point I was able to lay down all the pieces and see what the total build would look like. My son wanted a photo with it for size reference. He is 4'7" tall. The structure was a little over 13 1/2 feet tall here as it wasn't tightly put together.

Paint. Originally, I purchased 4 of the giant spray cans of white rustoleum paint. But the styroplast dries like plastic and as such, nothing sticks. According to the manufacturer, you can coat it within 12 hours with a top coat of paint but I had to let it cure a bit longer than that to sand off the drips. I did an adhesion test and the spray paint just chips off. I then purchased an adhesion primer from Sherwin Williams which should theoretically stick. I didn't try it though as I ended up using something called Macropoxy from Sherwin Williams. It is an Industrial coating my work was tossing as it as out of date/ spec for them and they could no longer use it. It is nasty stuff, had to be painted and mixed outside, and would happily eat the foam if it touched it. I had to hope that I didn't miss any spots with the hard coat or the rubber roof coat. I trialed a spot for adhesion on a sanded and non sanded area of the urethane hard coat and it stuck to both.

I don't think I would ever use Macropoxy again. Although it did the trick, it is horrible stuff to your health and the VOCs are terrible in general. It was free and it worked but never again.

Being that this sculpture is over 13 feet tall, I need to secure it. I tied some rope to the Unistrut anchor points and stretched it out to the ground at an angle, clearing the leg cover piece. This gave me the length I needed to stake down the structure but also not damage the foam with the wire. I made 4 eight foot long guy wires out of 1/8th stainless cable I had left over from a porch railing project. I added screw links to the Unistrut anchor points and planned on 16" J hooks for the stakes. The base of each leg has 4 outriggers on it which I plan to anchor down with 24" J hooks. I don't want this thing tipping over due to wind or weather. We get a lot of rain in the Cleveland area so he needs to be nice and secure.

I also added 2 ropes to the rib cage Unistrut to secure to my home for some added upper body stability. I have a historic home so it has wood trim and siding. I can put holes in it much easier than a vinyl sided home and I don't mind modifying my house to fit my displays.

I should have anticipated the ground not being level. The base pieces are adjustable down but I did not account for the 2" difference from left to right and front to back. I cut some plywood and 2x4s to shim the base plates and outriggers. I got it close to where i was happy with him being level and anchored the base down with 8 of the 24" J hooks. I then stretched the 4 guy wires out and staked them down. One of them hit the sidewalk so I wrapped the wire around the Unistrut once to shorten it and staked it down just next to the sidewalk.

The torso had to be lifted up and bolted on. A piece of the spine is then slid into place to hide the metal and support the structure. A fill piece is added to the back to complete the spine. I attached the arms to the shoulder joints by sliding the metal extension into the metal sleeve. The head then gets attached to the top by sliding it down over the Unistrut pieces into the PVC sleeves.

At this point the skeleton is also secured to the house with two guy lines made of a 600 pound test marine rope to keep him from falling forward with the wind.

I wanted to showcase his size compared to the original Home Depot 12 foot skeleton, so I set that up just on the other side of the sidewalk. In between is the sign for the St Jude charity drive we have participated in the past 5 years. Usually it is just a small yard sign. I had one custom printed to fit a full 4x8 sheet of plywood and it still looks small.

For fun, I moved his arm up and on top of the sign for a photo but I didn't like the look and his arms being down just seem natural for a Floppy Arm Skeleton.

I always get asked for a cost break down so if you read this far here it is.

Foam - $400

Fill / hard coat/ paint - $900

Unistrut / bolts $200

Anchors and cables and assorted consumables $200

So $1700? But the foam, unistrut, and paint were all discounted used, etc. To make one at full price with nothing found on marketplace would be $2500+

Does he glow in the dark? Not yet. I reached out to a US based company that makes glow in the dark coatings but it has been several weeks of back and forth trying to get decent customer service through email to sort out a pigment or coating that would work and not change the color during the day. Maybe I will add it later as I think it would be cool if he glowed when I turned off the display lighting.

I have had people say they would want me to build them one. As the Minions said to Gru when he was trying to garner the courage to make a phone call for a date with Lucy........Uh.... No. This is a 1 of 1. It took over a month of weekends and evenings, plus a few vacation days. Plus Lego gets really weird if you make money selling something that replicates their brand. So again, No, I'm good.

I also always get asked where do I store these. Well I have 40 days to sort that out. I typically store things in my garage, upstairs of my home, attic, basement, and where ever else it will fit. Luckily for my wife, the head is so large it won't get stored in the house. I do have an off site barn I can store some overly large things in and the pumpkin in my display will go back there again most likely. I wanted this guy to live in my shop but even with vaulted ceilings, he is too big.

Last....

This was created as part of my Skeletons for St Jude drive for Charity. It was built with my own money. I don't take a dime of any donation to the cause. You can see the nationwide progress Here on their website. 6 years ago when the gentleman started the cause with just his home in N Carolina, he had a goal of $10,000. This year, nationwide we should cumulatively have broken $1 million over the 5 years of fundraising as a group. That is 100X larger than the original goal. It is also why I built the Lego MegaFig 100X the original size.

I hope you like the build. Enjoy your day and Happy Halloween.