Chuck and Ryan's Build Tips

[DRL]

I must have missed that class. What about those silicone bumps? Don't recall seeing that anywhere.

Have not noticed any vibration in horizontal tail surfaces. But I have noticed that the engine seems to have "sweet spots" where it seems happier with less vibration.

chuck

With the windows open, they will either touch or be very close to the semi round head screws on the wing root fairing. I thought it called for the small silicone bumpers in the manual, but it may have been something we just discovered. If the windows have marks opposite those screws, they are likely touching from vibration when the windows are open, if not, nothing to worry about.

[ceslaw]

Thanks. Will keep an eye on that.

[ceslaw]

N Number

A scrap section of label material was taken to our local trophy and engraving shop and they made an N number plate. It works. Haven’t forgotten our N number since it was installed!

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[ceslaw]

Window Rattles

The first time the engine started, side windows open, the rear windows vibrated significantly. They are secured on all four sides but the center is much like a drum free to vibrate with a bit of a breeze from an open window. Headphones on, in flight, it is not that noticeable, but it was a squawk we wanted to resolve.

The solution was simple: screws through the upper center and lower rear portions of the plexi glass holding nylon straps around frame members. Here are the parts we used for both sides; all extra parts found in the totes (except the nylon straps):

(2) Nylon straps, 9/16”
(2) Nylon straps, ¾”
(12) AN960-10 washers (spaces the strap from the plexi glass)
(4) NAS 1515H3L nylon washers
(4) MS21083-N3 nut
(4) AN960-10L washer
(4) AN525-1032 screw

DSC_1031A.jpg

The first hole in the plexi was drilled 1” below the junction with the cross brace. The second was drilled in the lower rear 7.5” forward of the lower aft corner. Two wraps of friction tape were used. A Unibit was used to enlarge the hole to 7/32”. We were careful not to over tighten the nut. A 9/16” strap is used on the smaller forward brace and a ¾” strap is used on the lower rear brace.

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A dab of black enamel from a local hardware store was applied to the head of the screws.

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With the head of the screw painted gloss black it virtually disappears from view.

IMG_8751A.jpg

Even with the rear windows secured, we still fly only with one forward window open and below 80 mph, per the CC POH. The two screws on each window have resolved the vibrating window issue.

[Daveembry]

Window Rattles

The first time the engine started, side windows open, the rear windows vibrated significantly. They are secured on all four sides but the center is much like a drum free to vibrate with a bit of a breeze from an open window. Headphones on, in flight, it is not that noticeable, but it was a squawk we wanted to resolve.

The solution was simple: screws through the upper center and lower rear portions of the plexi glass holding nylon straps around frame members. Here are the parts we used for both sides; all extra parts found in the totes (except the nylon straps):

(2) Nylon straps, 9/16”
(2) Nylon straps, ¾”
(12) AN960-10 washers (spaces the strap from the plexi glass)
(4) NAS 1515H3L nylon washers
(4) MS21083-N3 nut
(4) AN960-10L washer
(4) AN525-1032 screw

DSC_1031A.jpg

The first hole in the plexi was drilled 1” below the junction with the cross brace. The second was drilled in the lower rear 7.5” forward of the lower aft corner. Two wraps of friction tape were used. A Unibit was used to enlarge the hole to 7/32”. We were careful not to over tighten the nut. A 9/16” strap is used on the smaller forward brace and a ¾” strap is used on the lower rear brace.

DSC_0002A.jpg

DSC_0005A.jpg

A dab of black enamel from a local hardware store was applied to the head of the screws.

DSC_0015A.jpg

With the head of the screw painted gloss black it virtually disappears from view.

IMG_8751A.jpg

Even with the rear windows secured, we still fly only with one forward window open and below 80 mph, per the CC POH. The two screws on each window have resolved the vibrating window issue.

Great idea. I'm going to incorporate it into my build. Thanks.

[David H]

Thanks chuck. Great upgrade. I have added the parts to my next spruce order list.
David

[Daveembry]

Covering the wings

I now know several thing: that the Carbon Cub wing is also called a “bad boy”; when Steve and Armando take their break; that it is way bad to get a wrinkle when gluing down the fabric on the wing tip; and that Mitch does not joke about Armondo’s height. I can’t count the number of times I have watched the wing covering video, but it has been really helpful and each viewing typically answered another, perhaps subtle, question.

1. The wing in the video does not have a landing light or extended fuel so a few tips follow. Before covering the top of the wing, Poly Tak is placed on the inner rib, and forward and aft locations where the fabric will eventually be cut out to expose the fuel tanks. A liberal ( I hate that word ) coat is applied and left to dry. I taped off the areas to assure a perfectly straight glue line, removing the tape before the glue was completely dry.

Attachment 3734

Glue is NOT pre-applied in the notch with the nut plates on the forward and aft edges in which the cover is placed.

After the first 250 degree shrink, the glue that had been pre applied is activated with MEK. After it dries the fabric over the tank is cut open, leaving about a 3/8 inch piece of fabric around all four edges. We cut notches in the fabric to avoid interference with the nut plates on rib number three.

Attachment 3735

Gluing fabric on the underside of the third rib is a challenge made easier by using a flat piece of metal. On the first rib we simply trimmed it flush using a razor blade since the fabric is under no tension.

Attachment 3736

The fabric needs to be tightly secured to the notch where the cover sets. A tongue depressor was used to make sure the fabric was tightly secured to the notch as the Poly Tak dried.

Attachment 3737

2. The same technique was used on the landing light.

Attachment 3738

After the 250 degree shrink, the fabric over the landing light opening was marked with a pencil line about ¼” from the edge all the way around. The line was then dabbed with Poly Tak to prevent it from fraying. An Xacto or razor blade was used to cut along the line, keeping it as straight as possible. This was then glued in place to create a neat, straight edge.

3. After repeated openings of the Poly Tak can it did not want to seal well due the accumulation of glue. When we started the second can a small section of Saran Wrap placed over the opening before the lid was placed to seal without the mess. After a few openings a new piece is used.

Attachment 3739

4. After the final shrink we noticed the second, bottom false rib had bowed slightly. If left, the row of rivets along it length would not have been in a straight line when viewed from front or rear. Accessing the rib in the space between the fuel tanks. we used tongue depressors to gently push it back in place, holding them with a folded towel, and making sure the tongue was not in direct contact with the fabric. We will leave this ‘crutch’ in place until it is Poly Brushed and riveted.

Attachment 3740

quick question here please Chuck. On the landing light (since it isn't shown in the video), you cut the fabric 1/4" from the opening but to clarify, was that 1/4" to the INSIDE of the landing light and that fabric glued back onto the landing light or 1/4" OUTSIDE the light leaving 1/4" of the nose skin bare? thanks

[TroyBranch]

I cut mine toward the inside and glued it in the corner. If you look close you can see the fabric line. You want to make the cut as neat as possible to make it look good.


It looked like this when finished.




Sent from my iPhone using Tapatalk

[Daveembry]

I cut mine toward the inside and glued it in the corner. If you look close you can see the fabric line. You want to make the cut as neat as possible to make it look good.


It looked like this when finished.




Sent from my iPhone using Tapatalk

Perfect. Thanks!!

[Daveembry]

Wiring, Part III

1. There is a shunt in the middle of the tray. We shortened the wire from the harness, PO3A10BK, and placed a terminal that would fit on the large bolt of the shunt. Note the insulated covers. The two fused wires, GEA10A22 and GEA11A22, are connected to the small screws on the back side of the terminal posts. Note carefully where they go: if reversed the current will read backwards on the G3X.

Attachment 4668

2. The G3X back up battery hangs from the ignition back up battery, which means the fabric we had so carefully extended forward had to be cut to gain access.

Attachment 4669
Before the fabric was cut away.

A curved section of thin aluminum about a half inch wide was cut to provide support for the fabric. The fabric was cut, folded over and poly brush used to hold it in place. The only time this will be seen is when the interior kick panel is removed to access the backup batteries but we wanted to keep it looking neat and the fabric taught.

Attachment 4670

If anyone is covering their plane and intends to use the G3X, modify the way the fabric is attached in this area to avoid this issue later.

Good catch here. Question.....how did you get the bevel look on your fabric there were you had to lower it to fit the G3X battery?