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Initial layup for the tailbeacon fairing. I wet sanded the 3D printed mold until it was smooth. Then I painted it, sanded some more, and covered it with thin plastic packing tape. I waxed the tape for release and laid up one ply to start.

Here it is removed. Only one ply so not very stiff.


I removed the bottom rib. Mostly sanded off the rivet heads and then drilled.


Here is my hack job. Came out terrible.


With the male mold inside, I'm gluing the cone in with 5 minute epoxy.


Next up: sanding, wet layups, and so on.

I'm laying up cone #2. Q/A didn't like the alignment so I ripped it out and doing it over. I'd take a picture but it looks exactly like the first cone layup picture.

Try #2. This one is not totally by eye. We figured out a good reference as shown.


Here is the flat pattern for the physical mount. I'll have a couple of 1-leg #8 nutplates installed. The 4 tabs will bend back 90 degrees and rivet to the fiberglass. The long tab will have a wire attached to it, probably with a lug, screw, and nut. This will let me ground the mount as shown in the tailbeacon installation manual.

I didn't finish before the weekend, so did a little speed tape and a quick flight test to 120kts.


Here was my first attempt at bending up the aft mount.


I could not get the bends tight enough to work, so I aborted the outside tabs idea and riveted tabs on the inside.

Note this lock ring is on backwards. I'm just using it for stiffness. This part was too loose to use.


The tabs are bent up nicely and I can see them with the flashlight trick. After it is riveted on I'll do a couple more plies, to both close up the end and hide the flush avex aluminum pops that aren't there yet.


Next up: drill and rivet. I think I'll get the tailbeacon on before I finish the bodywork and paint. That has sort of become my style. Still need to finish that on the fresh air inlet as well.

My sheetmetal piece is a bust. The mounting tabs are interfering with the skybeacon. Not enough room. Anybody doing something similar, I recommend making it bigger. What I am going to do to recover is make a laminate of glass, 0.025" aluminum, glass, and bond it into the cone. Stay tuned.

Bryan Cotton wrote:Adam has made a couple of lock rings out of HDPE on the CNC router.

What CNC Router do you use? Does it also do aluminum? I'm asking because I haven't fed my tool fetish for a while...

It's a Probotix Fireball V90. Found it on the local classifieds for about $300.


It is not awesome for aluminum. Too flexible.