Looking into the black "cable/hose" side conduits

A signature part of the helmet is the external black hoses or cables with multiple support points.

I've looked at these time and again, they may be different material on individual helmets, but at least one seems to have ribbing, another seems to have white markings or even writing on it. The writing may be just the gloss black ribbing reflecting light.

As seen in this screenshot however it has not only ribbing but a straight end termilal tube connecting into the end holder, possibly glued in place or more likely threaded into it.

Conduit on Claras Helmet from "Kill the Moon" with clear ribbing and thicker terminal toward the holder 

The Doctors helmet from "Kill the Moon", different helmets are made differently, this one has no terminal end tube but seems to have ribs all the way into the holder.

This leads me to believe they used a flex stem from a table work lamp. Something like the IKEA "Jansjö" worklamp.

The IKEA "Jansjö", the one standing is complete, further away is one disassembled with the LED PCB and wiring taken out and to the right is a boxed set unassembled from the store.

So being a Swede am I being biased toward the BBC propmakers using our cheap lamps, do I expect they ate meatballs and Lingonberries while working? :)
As far as I know, the Jansö wasn't being sold as far back as the first episode the orange space suit was used in.
No perhaps not this exact brand and model, but this type of table lamp using a flex conduit as stem. Perhaps earlier helmets didn't use this particular conduit, perhaps it was a rubber covered cable or an hydraulic hose. But at least two used in Kill the Moon have what closely resembles this excact flex stem and terminal.

The flex conduit terminal toward the hamp head Gouge is from me trying to pry it off the plastic head, it's loctite glued so I'll try heating it before trying again.

The flex conduit terminal toward the foot end, note the therading

At the very least it merits trying out a test on the helmet to see if it looks the part. The helmets being differently made also opens for using parts of the same flex conduit for several helmets.

Electronics adaption of Lantern

I recently purchased two black metal flex-lamps from IKEA to use for the conduits on the sides of the helmet. I'll talk more about those later, as this post is about the electronics I'm putting in the lantern.

When I disassembled the flex lamps I found a very nice PCB with an LED with wiring which runs on 9v.

These are not only very flat and small enough to fit in the housing, but it seems to me it's fairly likely that the original propmakers ended up with the same type of PCBs leftover from the lamps they would have disassebled to use the arms from. Pressed for space and with perfect leftovers that can run straigth off a standard 9v battery they'd probably have jumped at usng them.

It's at least plausible that the same type was used in the original hemlets, I haven't seen any disassembled top lanterns though so who knows. Good enough for a cosplay prop for sure though. :)

PCB wiring not shown

I also added red Diameter 5 mm LEDs and LED collars for the top

LED array will later be hidden under a cut up transparent reinforced garden hose

Cross section showing insufficient wall thickness for the collars, also note that the solid red LED covering isn't realistic but symblizes the lit up hose.

The LED collars need thicker wall support to function fully. They lock the leds with barbs when set in tight fitting holes, so I'll add that next. I uset the same type of collars on the Dalek gun previously, they're an electronics industry standard component today.

Update after modifications

As I noted in my last post several parts were too wide or too small, I've changed most of them now and as for every change the parts become more accurate.
I also added the cable, or as it may turn out to be -the steel flex conduit.

I finnally found the right size and shape for the ear piece front wedge nut!
It's an M8 easyfix nut but with semi-rounded top. I suspect the propmaker put the nut on a lathe and added a more visible radius to a standard nut. ;)

Screenshot detail from Doctor Who Episode "Kill the Moon"

This is the current ear piece

I still haven't changed the nut for the front wedge of the ear piece, as I noticed more pressing things to alter.

This is a screencap

This is my current model

These changes need to be done

• Triangles on the back edge need to be larger (I'd assumed they were the same size as the triangle on the frame of the real visor bu they're not)
• The screws holding the "camera mount" piece are smaller than M4. Most likely M3
• The vent plate is taller and/or more narrow, not like sided square
• The block with circles is overall smaller and has a proportinally smaller inner ring
• The edge of the back end chamfer lines up with the corner of the large body on the conduit
• Nut needs to be larger, also holes in plate are missing and the plate needs to be more angled so that it disappears in the front (dug into ear piece originally)
• top-back edge chamfers need to be larger and/or different angle
• Front chamfer toward visor needs to be non-linear, I had it somewhat like that but changed it back because it didn't seem quite right then. I'll just have to change it again. It probably needs to be cut with a complex curve surface to get just right. 

The V-cut at the front top of the arc also needs a chamfer.

Latest progress

Current progress of the helemt

I moved down the fan filter block as I saw it sits lower on the ear piece on the original props. 

I added all visible screws including cheese head screws.

I've also been working on the new better fitting lantern housing base but it's not finished yet.

Current work plan

 Coupling added

I finsihed the 5/16 coupling and added grooves to the top and bottom of the vent plate.

The 5/16 text as seen on the first screenshot is as close as I could get the original part, the font may be slightly off but not by much, however this is only used on the original props for the right side ear piece. The left one has what looks like an "8" on it. 
As they probably cut a real coupling in half and glued it in place it makes sense that the writing would be different on each side. I

I can also see that the top of the coupling is too wide. I'll change this.

Explaining the insert system

Ear piece showing some of the inserts exploded

I've modeled the parts to have insert details whenever they're raised from a surface in such a way that nooks and cranies that defy smooth sanding appear.

This mostly has no function mechanically for the 3D models, except in rare cases like for the nut fastening to the right in the picture above. The system is mostly there to enhance the 3D print post sanding quality later.

Insert as used on my Dalek gun (see my other blog), in this case it also served a mechanical purpose to easier attach led lights and wiring on the back of the tab

Finished Dalek gun, the handle parts use the insert system, the barrel doesn't and had to be sanded twice as long and with more attention to detail because of it. 

Why do this

If you print parts on a flilament printer you get lines from the layer by layer material addition process, think of it as cutting profiles out of sheets of paper and stackning them, the sides will get tiny stairway-like steps.
This needs to either be filled with primer or sanded down smooth to give realitstic smooth cast- or milled-and-polished-looking prop surfaces after painting. You can also smooth with acetone, but it melts the surface details and will often not remove all print lines without sanding beforehand anyway. Either way having insert parts like this help with the end quality from all of these methods and add just a little bit of time in after-assembly. Time and effort you save up on easier sanding.

Why? -So I can sand smooth here...

Why not just use an SLA printer?

It's true, layer lines are far less apparent with an SLA vat printer than a Filament printer simply because the layer height can be set much finer, but that process is messier with stinky chemicals and far more expensive per print. It's also far more uncommon to be able to print large parts.
As it is the parts on this project is about as large as I can fit in my Zortrax M200 which has a fairly large print volume for a filament printer.
It's also the printer I own and have at home so of course I'm adapting the models for optimal performance for my equipment. ;)

However, it's easy to fuse assemblies to print as a solid piece later, not so easy to separate like this so I get both choices when adding inserts according to my system.

Don't get me wrong, SLA printers are a dream for some projects.
Some day when the good ones are inexpensive enough and I have a well ventilated workroom for it, I'll get an SLA printer. at the very least for printing tabletop miniature models and perhaps if it's large enough even for larger parts. This means no more sanding required, or far less of it at least. ;)

Still work to be done, but things are coming together. 

This is where I'm at currently

I updated the work diagram:

Completed parts

Chin light, complete with separate housing and lens

Standard M4 nut with integrated washer for the Wedge plate, fastened with an M4 allen bolt from the inside.

Flanged and bent conduit completed, this is one of the most work intensive parts on the entire ear piece

Another view angle of the conduit

Comparison to screenshots

Clara Oswald (played by Jenna Coleman) from the Doctor Who Episode "Kill the Moon"

Of course the incomplete visor makes the model (made from IRL ProCap helmet measures) look narrower than the real helmets. I can see the scale on some parts (i.e. the hose connector end and the "mystery" clamp) need to be adjsuted. I also need to change the shape of the forehead plate.

I see here that I forgot to model the chin light housing and transparent core. Though this is one of the simpler parts to make every modeling is hours of work.

How mechanical surface modeling works

Some of you may wonder how you make models like this, especially the multi-curvature models are somewhat complex to make and requires the use of what CAD Designers call surface modeling, rather than straight blocks and cuts as most models are made.

I'll show how I made the lower ribbed side plate. This isn't a tutorial, just a short explanation of the process. If you want to learn there are free youtube video courses for most common 3D CAD systems on the market today., as well as plenty of companies teaching this professionally.

Making the ribbed side plate model I started from the helmet surface geometry.
I made an angled plane (as close to perpendicular as possible in this case) and make a cutting surface sketch.

I offset the surfaces to zero distance, making a copy of it to modify.

I extruded cutting surfaces from the sketch

I cut the outer profile, I then added Thickness to the cut surface (not shown).

Then I added the rib in the same way, cutting with an extruded sketch and in this case also cutting the sketch surfaces with the resulting cut surface and the previous surface.

The basic shape is formed but these are just surfaces (i.e. walls with no thickness) , not a solid possible to model with cuts for holes and the shell hollowing out I'm doing forther down. So I used the surface modeling command Knit to fuse the surfaces together and make a solid. 

Then I added radii.

Then I cut holes. 

I'm cutting with one plane here and a sketch is making the holes top direction and not perpendicular, I'll probaly change that later as it makes for a little crooked holes.

I marked the bottom for the Shell command. I choose to make the model 1 mm thick from the bottom with this.

Done. :)

Of course I skipped over some stages here but hopefully it explains some of the basics of surface modeling in 3D CAD systems and making it a solid you can more easily modify and cut to make holes.

I just finished the ribbed reinforcement plates and forhead plate, here's some pictures of the lower side plate.

 These were probably vaccuformed from sheet plastic originally so I made them in a similar hollow back/inside to be easily contoured to the helmet.




I now have all the basic parts modeled, though minor adjustment of parts including scaling and placement on the helmet need to be adressed.

I made a diagram showing the project status.

Screws need to be fitted as well. I have models of standard dome head screws I got from GrabCad. You can see them on the ear piece vent plate.