Preparing the nose & tail molds

I finished removing the nose cone mold from the Zephyr plug. I switched back to building the molds using fiberglass mat rather than carbon fiber. I built the tail cone using carbon fiber, and it makes great molds, in terms of very light, and they can look so professional! But it’s far too easy to leave air bubbles between the orange gel coat and the CF, which cause problems when sanding, finishing, and using the molds.

I put together this video of the nose-cone mold removal process:

I’m working right now on preparing the tail cone mold, getting it ready to mold an actual tail cone! I need to make a “workshop” tail cone. I call it that because it will be used and abused in the workshop; it won’t be road ready afterwards!

Once I’ve got the recessed area sanded onto the rear of the main body, I’ll use the workshop tail-cone to confirm the fit of the tail-cone over that recessed area is satisfactory, or to indicate where more sanding may be needed.

Months from now when the velomobile is actually built, I’ll also be using the workshop tail-cone as an aid when I create a chain protection cover.

I’ll cut large viewing holes at various places, so I can get a better view, how the rear wheel, chain + tensioner, suspension and the tail cone all come together inside…. it’s gonna be interesting to fit that together!

Here’s a photo of the recently amputated tail, and the carbon fiber mold that I made (and I was far too stingy with my spraying of orange gel-coat, fixed that with the nose mold!).


I have the nose cone mold cleaned up now, and it’s a much nicer mold to work with, it’s got a nice thick weight and thickness, and very secure flange. With the CF mold I’m always reminding myself to be careful handling it. It’s very lightweight, but at this thickness could easily be a crack or break if I whack it by accident (like that would ever happen….. )

Here are the two molds next to each other. They’re about the same size, square footage-wise.

The carbon fiber mold weighs 7 pounds, and the fiberglass/CF mold weighs 25 pounds (each had the same number of Clekolocs in use). The weight doesn’t make a difference when in use, I was just curious.

tail cone mold on the left, nose cone on the right.
Lower two parts of the nose-cone mold, heel bumps. registration dots on the mold flanges.

And the above and below photos show why I made the nose-cone a three-piece mold, rather than a two-piece top/bottom mold. I’ve designed it so the heel bumps are molded in and part of the nose cone, and the heel bumps extend further to the rear than the rest of the nose cone. That, combined with the curvature of the side walls, was going to make it very tough to get the final piece out of the mold.

nose-cone mold for the Zephyr

I’m pretty close to done with wet-sanding the nose-cone mold, then it’s on to buffing and polishing! I’m sanding this with the three parts all together. Since it’s such a large space inside, I can get my head and shoulder up in there, and as I said it’s a nice solid build. I know I’ve said it before, but this is my best mold build to date, particularly on such a large mold. Good to know I’m figuring it out 😉

I’m still waiting for a back-order of supplies, so I’m keeping busy with my wet sanding and buffing; here’s my outdoor workspace for this


Nearest way for me to get water near the workshop, but with winter weather coming I can’t use this hose much longer.

My workstand for wet sanding when I’m outside. I’m very nervous about any little wind though…

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