The plug is complete!

Progress has been slow but steady, even more so because of my living in a state with a “stay at home” request. Truthfully I’m very much a homebody anyways, but the request meant my career workload was cut down quite a bit, so I have had plenty of time to work on the Zephyr 🙂

The right side has come together, I’m finally satisfied with the symmetry of things like the knee bumps, and toe bumps, and heel bumps, ….. which also means that I’m satisfied with the finish of the upper surface. Shown here with the Milan’s hood resting on top; I’ll be designing a hood very similar, so it helps me with visualizing the look of the entire machine. And that faded blue half circle is about where the wheel wells will be built.


And the turtledeck has come together as well, although it does remind me of the head on the creature from the Aliens movies!


Early on in the construction I was a bit heavy-handed with the hot wire foam cutter, and the left side was, well let’s say it had the beginning of some cool design features, but I needed to re-build a large part of the left side back up in height.

If I had to do this amount of fill with ABF I would be mixing gallons of materials, and it’s not meant to be applied that thick.

I had previously ordered a 2 part expanding foam kit from Fibreglast, consisting of 2 quart sized containers, the A and B components. It’s sold as a 4.2 pound kit, which is the combined weight of the components. A 1 to 1 mix by volume ratio. This would be my first experience with it. I even set up a camera so I could make a video to share, but it was more boring than I expected….

I rotated the plug so that the left side was facing up, and built a quick little dam from sold coroplast sign material.

Work on the left side tail area, filling in with 2 part expanding foam.

It only took about an hour to cure up, and I could use the orbital sander to shape it. It’s much more resistant to sanding than the polyisocyanurate foam sheets.

It is more fluid when it’s first mixed up; I was kinda expecting this quick process, but the foaming doesn’t start until after about 45-60 seconds. When you mix together the 2 components and apply, it wants to run downhill, and it wasn’t easy at first knowing how to “control” it. Some areas would get a lot more “fill” than needed.


Best result was by using a 2″ throw away chip brush, pouring out or brushing on the foam where needed. And keep using that brush to re-position the resin as it starts to run. After about a minute, the foam gets more stiff and not wanting to slide downhill, then leave it alone to fully expand.

And I could start applying ABF onto the foam after only a 60 minute cure, it was a quick and reasonably priced way to fill in such a large area.


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