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By the way, the visor is not removable. Once I had positioned it correctly, more strips wrapped over the rim held it in place. It is fixed.
An idea for a next one perhaps.

Refining the shape.

One thing amongst a few learnt from going through the process.

It wasn't an afterthought. From the start I intended the helmet to have one, but as I've said I didn't make any plans and just made it up as I went along. It probably would be better to incorporate the visor from the start, but it just came out this way.

Up to this point the helmet consists of just newspaper and PVA glue. This means the cost of the materials was extremely low and could even be a little lower if free-sheets were used. The 750ml bottle of PVA of which there is still some, cost less than two pounds.
The next piece of material cost about the same:

I bought this visor as a single A4 sheet of transparent plastic from a stationary shop. Not too thick so that I couldn't bend it to the shape I wanted and not to thin so as to tear or flop in the wind.

I cut a piece from the sheet a bit larger than what I wanted showing, cut a slit in the front rim of the helmet and slid it into place. It was a little bit fiddly, but not too difficult.

Teaser:

Before I made this helmet I did spend some time looking at existing designs on the internet.

I remember seeing some that leave the rear section open at the bottom.

It was quite obvious to me that leaving the bottom uncovered would greatly reduce the effect, so I made mine enclosed.

If you've not read this already:

"If you've got a little bit of hair on your legs it will turbulate [sic] the air so you get a better flow. Now this in itself creates friction, so you don't want all your leg hairy you just want two thin strips, each about 10mm wide, just before the sides of your legs – though you will look really stupid.

You need the turbulent boundary layer – provided by these strips of hair - to get the air around the corner, and you need a smooth layer for it to flow over. But the leg is such a rubbish shape that ideally you want an aerofoil on the back of it." Mike Burrows

I wonder what he thinks about the moustache.

Smooth flow is best, but turbulent flow has better adhesion. Adhesion is good. Separation means low pressure where you don't want it. I think I understood this somehow and that's what the tail is so long and pointy; it decreases the need for good adhesion. I think.

I wasn't really taking it that seriously.
But I knew I wanted those ripples gone. Smooth, smooth, smooth it must be smooth and flowing was what I had in my head. I knew, intuitively perhaps, that those ripples would 'trip up' the air.

At the time of this there were no terms in my head like laminar flow, turbulent flow or separation. I was just doing what I thought looked and felt best.
Having since read a little about aerodynamics, I would say that I was aiming for a low Reynolds number and maximum laminar flow.

I will consider intentional turbulent flow in any future projects.

^^
Huh?
Ahh
Mmm

Looking at these pictures again now I remember how much glue I got all over my fingers every night for several nights and that satisfying feeling of peeling and rubbing from one's fingers dried on PVA.

At this point I was pretty happy with the overall shape of the thing. But it still needed some work to get the surface even and smooth.

I experimented with applying strips of differing thickness, more glue, less glue, lots of small pieces, bigger pieces.

Getting rid of those ripples was tricky.

Missed one. Sorry.

are you related to skrtluv?

No.

Now for a couple more pictures:

It's come on some way from the 'ear flaps' stage.

Yet, still some way to go.

Right,
Let me answer a some questions,

Will you be including a layer of tin foil in the lay-up?

Funny. Next time.

I think your knees are too close to your elbows but otherwise where do I buy one of these custom lids?!

Not currently taking orders. Price would probably be somewhere in the region of £1000.

Is that Kurt Cobain?

Thanks for that. I never got one of those, but now I feel like I have.

op, can you be persuaded to venture into footwear perchance?

What do you have in mind?

amazing. i can see this idea taking off. Perhaps there'll even be a homemade aero helmet ride to brighton

List...

"fatto quotidiano" helmet?
it looks like :)

Can't remember. Must have just got back from trip to Italy. Mostly Guardian I think.

^^^(lots) another music student?

Former.

Some great interest here. So many questions...

Next picture:

At this point, using the Mk1 eyeball that I have exclusive access to, I discovered that the helmet was not perfectly symmetrical.
This was a little bit annoying.
The left side of the helmet (our right) looks better to me. I think this must be something to do with being right handed.

Please excuse the untidy workspace.

These next pictures show the 'skeleton' getting wrapped with a skin.

I didn't really know what I was doing. I just cut up and folded strips of random journalism, saturated the strips with PVA and wrapped them on the frame. The main thing I tried to do was keep the thing smooth and the lines long and flowing.

I was pretty pleased with the progress.

Evening all,

More pictures coming up...

Don't worry about that green hat; all will be revealed.

Morning picture:

More this evening.

That's a generous offer rwn, thanks. I think it'll be some time before I get around to taking the necessary measurements for that.

Thanks for all the enthusiastic encouragement. I thought there might be some interesting responses, but I didn’t expect quite this much.

In the first picture I have shown you we see the helmet already in a state of some substance. It didn’t really occur to me at that point to take pictures of the project for posterity. I took that picture actually to get a look at it side on to make a judgment of the angles.
I know it does look a bit funny and the ‘tache doesn’t help, but it does get better.

Throughout this project I never made any plans or drawings, I just made it up as I went along.
To get to this point I first donned a scruffy old woolly hat and then wrapped it in cling film. I considered using a balloon, but decided to use the actual thing for a better fit. I poured a load of PVA on top, spread it all around and started applying strips of newspaper. Eventually there was enough of a structure and it had started to stiffen up that I could take it off. Hardened, trimmed and edges reinforced I now had a good base to start working on. As I say, that first long wrap-around strip that looks like ear flaps was just a rough guide for angles.

I set my camera-phone timer, assumed my high-speed cycling position and from that image I could see that the ‘flaps’ were well off and that actually the tail should extend pretty much straight back from the bottom edge.

The next pictures show the first skeletal parts of the tail.