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20 Nov 2020 Update - Left wing is finally clean and prepared for covering. Took much longer than I anticipated. All of the old bond, masking tape, and anything else covering the wing is now removed. I used mostly an MEK Substitute to do the bond removal. Masking tape came off with a glue gun, scraping and MEK substitute.
The wing stands are already proving their value. I bought a couple of Harbor Freight dollies to slip under them and rolled the wing outside for zinc phosphating. I only applied the zinc phosphate to the parts that were originally covered with it. All other surfaces were completely cleaned. The wing is now prepped for covering. Next step is to add wing inter-rib brace tape and then apply the leading edge felt.
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21 Nov 2020 - Since the Plexiglas panel behind the instrument panel control knobs was in rough shape with flaking paint and cracking plastic, it needed to be replaced. Thanks to Ken and Lorraine Morris of Taildraggers Aviation, I was able to obtain one of their post production panels.
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Rather than paint the back of the new Plexglas panel the 'India' color to contrast with the 'Silver French Gray' instrument panel back color, I decided to make a back cover for the Plexiglas panel. Made from .020 aluminum, this will be painted 'India' instead and placed behind the Plexiglas, sandwiched between the panel and the glass. Then the cables and control knobs will be added back into the panel.
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Hope to get some more work done during the Thanksgiving break next week. All for now, Steve
24-27 Nov 2020 Update - Managed to get some work in this week. I am learning that whatever amount of time I think something will take to multiply that by at least two and sometimes even three. After thoroughly cleaning and prepping the wings, it was time to actually start adding things back to the plane! Hard to know how much to prep but the one most common piece of advice from everyone on wing covering was to take the time to do the prep right.
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I've gotten a few queries on what zinc phosphate I used. It is called Temp Aviation Zinc Phosphate Primer. I called the tech rep at Stewarts Systems to ask if there were any issues. The helpful gentleman said it should be fine and he was encouraged that I was prepping the original zincked parts.
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Continued next post....
Last edited by regular122 on Fri Nov 27, 2020 8:57 pm, edited 1 time in total.
24-27 Nov 2020 Update (Continued) - Once everything cured, I added 1/2" inter-rib brace tape, remembering to make sure to run the ends under the rib not on top of the rib. For fun I penciled in the date on the cloth tape so somebody 25 years from now can see the note.
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regular122 wrote: ↑Fri Nov 27, 2020 8:48 pmI am learning that whatever amount of time I think something will take to multiply that by at least two and sometimes even three.
My rule is to multiply my best estimate by 4. It takes twice as long as expected, then you have to do it over using what you learned the first time. I've also learned to never start anything that takes more than an hour. That way I can usually finish the same day.
Four times sounds about right John. This forum has helped avoid some of the redos though!
The Ercoupe, a 1941 / 1946 hybrid with 1946 plate, belongs to my friend who is allowing me to do the repairs in his hangar. Belonged to his wife's uncle and has been in their family for a very, very long time. I hope to convince him to start getting it back airworthy after the 140 is done. It is in pretty good shape but hasn't flown in several years.
24-27 Nov 2020 Update (Cont) - Next I added 1/2" Superflite reinforcing Tape as the anti-chafing tape. It is strong and easy to control. Hopefully it will be easier to remove, too, for the next covering. All the masking tape removed from the wing became an absolute goo under MEK and/or heat gun efforts. No good way to get it off. So at the end of today, the wing stands cleaned, zincked and taped. We also checked all ADs while the wing is open. I am still hoping that a Grimes G3602 / D3040A Landing Light turns up. We will lay new wiring for it regardless but leave the unused original wiring in it for nostalgia.
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Last of the 24-27 Nov update Continued next post...
Last of the 24-27 Nov 2020 update - Taping took longer than expected but then again I may have been a little thorough. Tape is cheap though. I can't imagine trading $10-15 saved on a roll of tape for some sharp edges and a poor surface.
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The interior is moving along. I took Matt the newly acquired panel and fabricated back plate along with the decals and hub caps. Took this nice picture of the instrument panel with the panel covers lightly hung on to get a look. The contrast and colors look very good to what I was thinking and to what Ken and Lorraine Morris had shown in some pics they sent.
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Gary, the friend who is leanding me some hangar space to work on the wings and the A&P supervising much of my work, manufactured a pitot tube for me today. He used the great tech sheet notes and the forum Cessna 140 Tech Manual I bought through the Association. That thing has already more than paid for itself.
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That's it for now. Winds are supposed to be pretty calm tomorrow so I hope to get a few hours flying in. Steve
11 Dec 20 Update - I was not able to get to the wing last week but made a little more progress today. First off, we received the paint from Stewarts for the landing gear and metal items. With the interior mostly finished, Matt is shifting to the gear legs, struts and other metal parts. The fuselage is looking really good now with the first decal in place.
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I was also able to find the ever elusive Grimes Landing Light. Waited almost a year to find one after I had passed one up earlier that was a bit high at $850.00. Patience paid off thankfully as this one cost $215. Now I have to recondition it for installation in the wing. This model is the D3040A. Both this model and the G3602 are in the parts manual, identical as far as I can tell. I believe the USAF used the D3040s (D3040E) in the T-37 but on a military voltage system. I had even thought of buying one of those and converting it but now it won't be necessary.
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11 Dec 20 Update (Cont) - I cut the felt for both wings and attached it to the one I am covering now (the left). The felt is white, about 1/16" in thickness relaxed. It will tighten well with the Eko Bond and cope the leading edge into a nice smooth finish to soften the rough spots from rivets, screw heads and overlapping edges of aluminum. After cutting the piece, I then rolled it. Then I applied M77 Spray Adhesive to the leading edge and starting at the wing root, I unrolled the felt and worked my way to the wingtip tightening, lifting and adjusting as necessary. Once that was accomplished, I flipped the wing over and sprayed the other leading edge surface and smoothed the felt into place. It went on very nice and was easy to apply.
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