Recently on a preflight of my 750, I found a mud dauber nest on my elevator cable. I tried to pull it off the cable and retrieve it, but all I succeeded in doing was breaking it off the cable to fall down into the fuselage!  I got a piece of stiff wire and a good light and peeked in the vertical gap between the rudder and the fuselage, thinking I could poke the wire into one of the nest's holes and lift it up and out of the top of the fuselage where the cutout provides clearance for the elevator horn.  When I looked through the gap with a good light, I was horrified to see multiple nests!  Yikes!

Even worse, what you can't see in the above picture is that there was another large nest just inside the lightening hole on the right side.  None of these nests were obstructing the controls or presented an immediate hazard, but it sure was a mess!  I popped loose any nests that were attached - there must have been at least a half pound of them!  Here's my "collection:"

I then vacuumed up any remnants and used a moistened rag to clean away the residual dirt.  I did a thorough inspection deeper into the fuselage and didn't find any more nests, thank goodness!

Always looking to "make lemonade out of lemons," and since I have the rudder off and access to the nut securing the tie-down ring, I'm going to install a stainless skid under the ring to provide a little extra protection for the rudder should I ever accidentally drag the tail on take-off.

It was shocking to see how much crud those pesky daubers could deposit in the tail!  This was despite keeping a couple of Rescue Wasp Trapstiks hanging at all times right above the plane.  The traps really are effective - they get almost entirely coated in trapped dirt daubers in no time ... but, obviously, they don't get them all!  I wish there was an effective repellent that could be placed in the plane's cavities, but I'm not aware of any.

The take-home from this is that if you find mud-dauber nests attached to your plane - look further!



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 Here in Idaho mud daubers are not as bad, but other wasps and bees are a pain! In my farm electrical boxes and other small areas I use insect repellent cow ear tags. In a plane they could be safety wired in place and a bag could last for more than one season. Vet and farm supply stores sell them. If one does not work, try two or three. 

Leaf cutters and wasps like to live in the electrical control boxes on irrigation pivots and cause the pivots to go haywire and wreck, at $50-100k each, not my idea of fun. An ear tag in each box in the spring keeps them out. 

My real burn is nest building Starlings. Failure to pre flight the engine area for nests in the spring time is an in flight fire waiting to happen.



The cow tags are a great idea - neat, clean, and easily safety-wired!  I'm in the heart of Tennessee's cattle country and there's plenty of ag supply stores - in fact, my lessee usually keeps a couplel hundred head of cattle on my farm, so I'll bet he's got plenty of tags.

Now, just need to figure out some sort of system to be able to replace the tag annually without having to take off the rudder.  I really ought to install an inspection plate and that would make it easy (one could even make a mount for the tag on the backside of the plate) but I really hate to cut another hole in my beautiful paint job! Ha!  Of course, in the event the daubers ignore the cow tag and build a nest anyway, the inspection port would allow me to easily clean the area.

Thanks again for a great idea!


Sorry to creep my own thread a bit, but has anyone installed an inspection plate in the area in the first picture?  It looks like the only place where I could put a hole big enough to admit my hand (I can just get my hand through the 95mm i.d. lightening hole in the Rear HT Frame) would be on one side or the other upper rear corner of the fuselage.  If you've done this, any more info or photos would be appreciated!  If I undertake this, I'm naturally going to run it by Zenith to ensure there is no structural compromise - after all, all this area does is simply hold the tail on!  ;>)



I emailed Roger and he said it was no problem structurally to add one or even two access holes into this area.  He recommended I simply copy the Cruzer design and provided a drawing and photo:

Cruzer Drawing

Great Zenith support, as always!


How is the access panel retained?

Roger said, "I have one screw in the center with a metal plate with a nutplate on the back side."  I assume the metal plate is a rectangular strip narrow enough to slip through the hole but long enough to catch the inside edges of the hole when the cover is centered.  Tightening the screw clamps the backing plate and the inspection cover together.

Sounds to me one would likely need to chase the nutplate threads with a tap so the machine screw turns easily - otherwise, the backing plate would spin with the screw!  I've seen similar plates with a "springy" rectangular strip riveted to the backside of the cover.  You slip one end of the "springy" strip into the edge of the hole, push it over far enough for the other "springy" end to fall into the hole, and then slide the cover back half-way.  Spruce sells them both slightly domed and one with a recess so it won't slip off-center.  I think they're intended for fabric coverings, but don't see why they wouldn't work with our thin aluminum fuselage skins.

If this is standard on a Cruzer, perhaps one of our Cruzer builders can provide better details.


John I sent u a message today on your friends section


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