Introduction: "To Infinity & Beyond!" [Making a Correx SpacePod to Boldly Go to Space and Back]
I was part of a team at DesignSpark, tasked with sending a Superman figurine to Space in a SpacePod, then have him 'jump out' of the pod and free-fall back to earth. I was responsible for making a SpacePod capable of surviving the assent (-40C, wind, rain, cosmic radiation), and ensuring that the 4K cameras and GPS equipment all survived the 5m/s descent to Earth. (Other brave Superheros may apply).
I had recently just made a Card Rabbet Tool for making making fancy prototypes out of corrugated card... However, Card was not waterproof... luckily I realised that this tool also enabled me to work with Correx (like Corrugated Card - but made of out plastic, and therefore waterproof!). Correx also has a great strength to weight ratio and would absorb the shock of the landing. It was also cheap at ~£10/sq.m.
This Instructable starts right in at the deep-end, and give some insight into how to design something in CAD, and export it as a 'net' (2D template of a 3D form), so that it can be assembled from a sheet material. If you are new to using this tool, you may want to check this starter-guide out first. Once you have the idea, this Instructable can help you make a huge variety of forms, for prototype, architectural models, sculptures - and even Space Missions...
This SpacePod was designed in the style of Felix Baumgartner's supersonic freefall. Now, although this is clearly not as dare-devil as Felix/RedBull's efforts - what is amazing is the comparatively tiny cost of such a mission like this: Electronics that would have cost millions only a few decades ago are publicly available and ready to roll, from companies like Raspberry Pi [in the Sky]. It's inspiring stuff. For the full electronics low-down, read about it on the Design Spark blog, and video in Italian, here, but until you order your PCBs, do look through this Instructable and see how cheaply you can get a SpacePod together!
PS - Please vote if you think this inspired you to get more out of you favourite action figure...
UPDATE: Thanks for the votes! I appear to have made it to the finals of the formlabs competition - and bagged a super Instructables T-Shirt!
Step 1: Make a 'Net' of Your Model
Making a 'Net' is done by taking all of the surfaces of a 3D model, and 'flattening' them onto a 2D surface. This allows you to cut the shapes out - and then re-assemble them, knowing that they will form an accurate 3D shape.
I used Sheet-Metal software to design this, but many other alternatives, such as Pepakura will work too. Print everything out (use the 'tile' or poster-print function on your printer to do this for large models like this one)
Once you have your Net, lay it down on the Correx (perhaps stick it lightly with masking tape, or better yet, use a little spray-mount) and cut around it (cutting through the paper and the Correx as you go). It may require more than one cut to get each section cut free, and take care when cutting the Correx, as the direction of the fluting can make it unpredictable when applying pressure with a craft knife.
TIP 1 - Remove your paper net, and write in permanent market on the inside what each piece is. Inside is best as a. you probably won't see it and b. if you do need to remove it - washes off with IPA.
TIP 2 - if you have used spray mount, keep your Nets/templates somewhere where they cannot touch each other (I hung mine on the back of my door). Trust me, you'll regret it if you don't have some system like this to stop it all sticking together in one big mess!
TIP 3 - If you have a symmetrical design, you can just flip the nets, saving you time on printing and preparation.
- Superman Net - Floors.pdf
- Superman Net - Sides.pdf
- Correx Shell V2.SLDPRT
- Correx Shell V2 - Form.SLDPRT
Step 2: Start Assembly
The 'Card Rabbet Tool' will cut a fillet out of one side of the Net. Some consideration will be required to ensure that the right faces are aligned. Try laying everything out on a table/the floor to think through the sequence - it will save mistakes later on.
The Tool has been designed to prevent cutting oneself, but as always, ensure that your fingers are out of the way of the tool's path at all times, and ensure the blades are not blunt.
To go round corners, slowly but firmly turn the Tool while progressing round the outline. If unsure, try on a scrap piece first.
When starting to glue the assembly, begin with the most 'visual face' (i.e. the best part of the model), that way when you work around and seal the unit, the front will look great.
Apply glue down the inner seams. This is where the Rabbet/Rebate joints along all the surface really help, as they not only allow the surfaces to come together neatly, but also to allow a greater surface area for the glue to bond to. (I was surprised at how well this works and the joins are very strong - try it on some scrap Correx to compare it with a standard 'butt-joint').
TIP: As mentioned in the 'beginner's guide' to working with this method - use Sellotape / Clear Sticky Tape to pre-align all the individual parts of the SpacePod together. This not only keeps everything aligned, it stops glue spurting out and making a mess and/or burning your fingers.
Step 3: Finishing Touches
You can use the Rabbet Joint to inset different colours, as shown with the yellow Correx inside the blue.
Assuming you are going to put stuff in your Pod/Capsule and take it out again, you don't want to entomb it, so I'd recommend putting some doors/hatches/flaps for access in your build, also with 'D' holes (3rd picture) so you can get your finger in behind it.
Another tip would be using double-sided Velcro strips to attach any electronics gear to the inside of the pod. Easy access and room for adjustment outweigh any benefits of carefully crafted housings, and also Velcro is a natural shock absorber.
Many cups of coffee later, and a lot of mess later - you will have Correx Model!
Step 4: Ready for Action!
I hope this has been useful. Please post any pictures of any new iterations of the CAD you do.
Rabbet Tool (Instructions & CAD Files [FREE!]): http://www.judepullen.com/designmodelling/card-rab...
Rabbet Tool - to buy from Shapeways (if you have no access to a 3D Printer): https://www.shapeways.com/designer/jude_pullen
Beginner's Guide (to using the Rabbet Tool on Correx): https://www.instructables.com/id/Make-Waterproof-Prototypes-From-Sheet-Correx/
Design Spark: http://www.rs-online.com/designspark/electronics/e...
Design Modelling: http://www.judepullen.com/designmodelling/