Chapter 19/20/23 – Spinner mockup

Thankfully I was greeted this morning with Max still whirring away printing out the prop spinner flow guide mod test mockup.  It would still take nearly 2 more hours to finish up the print, which is when I grabbed this pic here.

I then set it next to my current flow guide to show the stark contrast between the shape and size between them.

Another couple shots of the current flow guide and the test mod mockup.

Entering the shop I immediately chased out 2 squirrels that think the workshop is their residence.  I then saw this massive spider on the wall… at least 2.5″ inches across the legs.  I yelled at him for letting those damn squirrels into the shop!  If you’re gonna hang around ya gotta do some work!

I then installed the test mod mockup for the prop spinner flow guide.  It was a tight fit, but it went right on.

Here’s the clearance between proposed prop spinner mod configuration and the lower cowling… it makes me think that I may just very well add a very slight curve to the flow guide.  I’ll assess and see.

Another couple shots at the side of the flow guide mod.  I’m thinking I may add to the flow guide a bit by simply taking the front edge straight forward with a 1″ lip… with a nice radius flaring out to the aft expanding flow guide.

I then mounted the prop spinner.  Although my measurement on my 3D printed flow guide is correct, I think that the nearly 1″ wide mounting flange on the flow guide for the spinner is not a straight cylinder as I printed it out, but actually expands out a hair as it goes forward.

The spinner was a hair bit wider in diameter than the flow guide and I needed to put some duct tape internally to make it a snugger fit.  I then set the top cowling in place.

Of course this still provides a good idea as to how the spinner will look installed. Remember, the top cowling and exhaust pipes have yet to be trimmed to final configuration.

After a bit of staring down the prop spinner and pondering various aspects of its upcoming installation, I then got to work on the winglet intersection fairings.

I’ll note between last night and today I did a fair bit of research (RE-research actually) and observed that various builders had used a 2-ply BID layup as the foundation for their fairings.  I decided to use very light wood pieces cut nearly to the exact shape I wanted and then add carbon fiber for stiffness and rigidity.

The trailing edge of my left wing is a hair thicker than the one on my right wing, so I used 1/16″ Balsa wood (which I just bought) for the substrate on the left and some on-hand 1/32″ Birch plywood for the substrate on the left.  The difference of thicknesses in these areas will be flushed out with pour foam and subsequent micro finishing.

After cutting the actual left and right wood substrate pieces, using the cardboard template I made up the other night, I then cut some carbon fiber and peel ply for each one as well.

I then laid up the carbon fiber on the wood substrates and peel plied the layups.

I’ll point out that the carbon fiber is only going on these pieces and will not be securing any component to any other component… thus with these in place between the wing and winglet, and secured with E-glass fiberglass, any twisting, flexing or bending moments will be primarily at the joints secured by the fiberglass—and not specific to these carbon fiber reinforced wood pieces.

Since these were fairly small layups I used fast hardener, and had enough epoxy left over in my cup that I didn’t want to waste it.  I quickly unboxed my roll of Lantor Soric and cut approximately a square inch off of it.

I then wet out a scrap piece of BID, slathered up both sides of the Lantor Soric piece before covering it with another ply of scrap BID.  I had to hurry because my epoxy was starting to cure in the cup and was turning the consistency of thick honey.

After the carbon fiber and peel ply was in place, I then covered each of the fairing pieces with Saran wrap before piling on some sheets of steel and weights to compress the carbon fiber/wood substrate assemblies and keep them nice and flat (note my trimmed Lantor Soric test piece).

A couple of hours later I removed all the sheets of steel, the Saran wrap and the peel ply.  I then left the carbon fibered covered wood winglet intersection fairings to cure overnight.

And called it a night!

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