New Panel Overlay - A Work In Progress

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brian.olson
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New Panel Overlay - A Work In Progress

Post by brian.olson »

Ok ... my wife are going down another deep hole, but it's been fun thus far.

First off, feel free to refer to post: viewtopic.php?f=24&t=15342 where I asked a question concerning the re-chroming of the yoke shafts and re-painting of the yokes. Lively conversation and we've been making progress. In summary: I was able to polish the yokes enough to convince myself that I didn't need them re-chromed, and I bought the complete power tool inventory out of several big-box stores simply to drill 3/4" inch holes in several 1-1/2" solid Delrin balls. Unfortunately, during that process, I also opined something to the effect of "why not create a new panel overlay?" Or, something stupid like that.

This thread is for other newbies like me, who - upon imbibing sufficient amounts of fine bourbon with the spouse - decide to embark upon said project. This will either be my victory lap, or my epitaph. Bear with me, as I tend to become verbose in prose and in photos. We will all learn something in the process (and it could very well be that my purpose is to serve as a warning to others).

Here we go.

Last weekend, my wife and I pulled off the decorative panel overlay in 62C. It wasn't hard as it was only secured by copious amounts of velcro. Wasn't me, I swear. As near as I can tell, at some point in 62C's history, when equipment was added and subtracted, the original overlay was removed and someone crafted a new overlay. It's served well, and looks ok. Note that the marker beacons and the switches (I believe they were - at some point - a rudimentary audio panel) became inop as the equipment was removed. So, at the very least, we're going to clean things up a bit. I would *really* love an original decorative overlay, but since I put in some glass into the panel I think we'll be satisfied with original-ish (much like the interior we put in two years ago: not original, but certainly not modern either. Original-"ish").
Panel Overlay - Front.JPG
(The panel overlay, as removed)
Panel Overlay - Rear.JPG
(Rear view of the panel overlay)

Trolling these illustrious Forums I discovered a few other brave souls who have solved this problem before me - creating fiberglass layups as well as sending a mold off for vacuum-forming. We decided to be bold: we are going to create a new panel overlay custom fit to the plane out of carbon fiber. Actually, we're going to create two of them: the first will be natural carbon fiber gloss with lovely curves descending into the instruments themselves. The second will be more original-ish: still carbon fiber, but painted either with the original Cessna clay or with the tan that we used elsewhere in the interior.

To begin, I traced the original panel overlay onto 1/8" MDF to serve as a draft cutting jig. The original overlay didn't exactly fit the instruments so we used this as an opportunity to fine-tune spacing and clearance on the panel.
Cutting Guide in Plane.JPG
(MDF draft cutting guide in plane. We're noting final adjustments we need to make. Also note that there is a bit of a gaping hole above the plexiglass overlay due to some historical instrument that was installed and then later removed by owners unknown. We'll be fixing that during this process.)
Cutting Guide Final Markup.JPG
(Final mark-ups on the cutting guide)

From there, I cut the final pre-mold pieces from 3/4" MDF. For the first - which will be raw vacuum-bagged carbon fiber, I cut and routered the edges and holes for the instruments. I'll cut the square hole for the Garmin G5 once it's done, as I want the edges to be flush with the instrument.
Mold Plug.JPG
(Final mold plug in 3/4" MDF. Note that the wide-angle lens on my phone is distorting dimensions and alignment a bit.)

For the second piece, it will remain flat with no instrument holes cut out. I will cut the holes out of the piece once it has been vacuum-bagged, since I want sharp edges. I am creating test bezels on my 3D printer with the hope that we will be able to answer the question "where do I find bezels?" with a simple "I'll just print the buggers".

Next Steps:

1. Tomorrow, or this weekend, I'll lay down two coats of epoxy on the 3/4" MDF mold blanks, sand and polish;
2. Once prepped, I'll create negative molds using a coat of gel coat followed by several layers of carbon fiber and fiberglass matting;
3. Once dry, I'll sand and polish the molds ... and then they will be ready to vacuum-bag the final product out of several layers of carbon fiber.

More to come ...
Last edited by brian.olson on Thu Oct 15, 2020 9:44 am, edited 1 time in total.
Brian
1950 170A
N5762C s/n 19716
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GAHorn
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Re: New Panel Overlay - A Work In Progress

Post by GAHorn »

Brian... Your “style” of authorship and your “intent” of purpose are WONDERFUL and I hope you’ll keep your courage up and continue to post your ideas and projects! I LIKE the way you think and work! :P
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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rschreiber
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Re: New Panel Overlay - A Work In Progress

Post by rschreiber »

Great intel on your project, Brian! Keep the updates coming!
Ryan
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brian.olson
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Re: New Panel Overlay - A Work In Progress

Post by brian.olson »

Well, not making as much progress as I had hoped. Busy work schedule has had me glued to my desk lately. However, I was able to get out this past Sunday morning - and a lovely morning it was - and take care of my monthly VOR check, followed by a little practice flying holds over over VOR. The GPS makes it as easy as yawning through a video game, so I kept challenging myself to go back to my training and use the nav radio and timer rather than the magenta line.
Holds.JPG
(Lovely morning to practice flying holds. Approaching the Lagrange, GA VOR)

Back to our project. I finished the final sanding on both MDF mold forms and secured each of them to a separate piece of MDF to serve as a bit of a "shelf" for making the molds.
Mold Blanks - Sanded.JPG
(Final sanding of the raw MDF forms)

I was able to lay down a heavy coat of epoxy to cover the forms and extend out far enough to create a "lip" for the mold(s). While relatively smooth I still need to sand, and then apply filler to fill any pin holes. That is still to be done. I'm using the West epoxy system for the epoxy. The quart-size container says it's enough for approximately 90 square feet of material - which should be more than enough for my purposes. So, naturally, I went back to Aircraft Spruce and bought two more quarts. Because I know how I work, and my ability to screw things up and re-do them. But heck - it's all in the name of science, learning, and having fun. So, yeah ... I have enough epoxy now.
Mold Blands - Epoxy.JPG
(Mold blanks with a single coat of epoxy)

That's about the extent of the progress we've made over the last week and a half. Not much, but progress is being made.

Next steps:

1. Sand each mold blank smooth, apply body filler, and sand that smooth. Any perfections at that point will be transferred to the mold and then to the final product, so I need to be careful;
2. Create a mold from each blank using the gel coat, carbon fiber, and fiberglass mat;
3. Vacuum-bag the final parts.

More to come.

Oh ... hitting the way-back button to early last month, when 62C was in annual. After our interior refresh of two years ago, the only thing that I was really unhappy about was the back bulkhead. It never fit well, was difficult to attach, and rather bothered me anytime I put luggage into the plane. My A&P suggested fabricating a new bulkhead using some sheet aluminum, which could be easily and securely fastened and provide enough assurance that any baggage would not migrate back to the tail of the airplane during turbulence. I watched him quickly create a template, cut out the form from .032" aluminum sheet, and drill the holes.

I took the newly-fastened bulkhead home where my talented bride took over. She cut out some left-over vinyl (that we had bought from Airtex two years ago, for this very purpose, but never actually used) and glued it to the bulkhead.
Bulkhead 1.JPG
Once that was complete - and with the seats and carpet still out of the plane at the conclusion of the annual - I was able to put the bulkhead in place and re-attach the back panels in the luggage area. Problem solved! I feel MUCH better having the new piece in place and not only does it look nice(r), it's going to be easy for the A&P to remove during future annual inspections.
Bulkhead 3.JPG
But ... whatever shall we do with the leftover .032" aluminum sheeting? We'll have the rest of the story, after this brief commercial break...
Last edited by brian.olson on Thu Oct 22, 2020 12:15 pm, edited 3 times in total.
Brian
1950 170A
N5762C s/n 19716
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brian.olson
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Re: New Panel Overlay - A Work In Progress

Post by brian.olson »

With the leftover .032" aluminum sheeting that my A&P used to fabricate the new bulkhead, I decided to take care of another small project that had bothered me - not a lot, just a little bit - every time I got into 62C. Our beautiful interior contrasted with the old busted-up, battered, ugly heel plates and they just screamed to be replaced. I consulted my A&P about it and with a wisened-eye and smile he simply said "just make new ones". So, I did.

As I am still very much a newbie to all of this, I have this mental pull to leave things alone. Don't touch what's in the plane. And I'm learning that many of the things that I see, that I touch, that seem "original" and "untouchable" were likely changed once or twice by someone - maybe a newbie like me, maybe someone older and wiser - in the past. Probably in much the same way with the same motivation: wow, that looks old and busted; let's take a couple hours and make a new one. Mind you - I'm talking about cosmetic stuff: interior fabric, panel overlay, heel plates. And it's humbling and empowering to realize that I can do some of it too. All under the watchful eye, and with consultation, of my A&P.
Heel Plates - Before.JPG
(The original heel plates look terrible, yet still functioned well)

So I took the old busted-up heel plates - which were still out of the plane due to the annual inspection - and drew up paper plans from them. BTW, in case you have ever had a nagging curiosity about this: Aeroshell W100 makes excellent weights to hold down paper patterns in the hanger. Cutting them a little larger than needed allowed me to custom fit the final cut.
Heel Plates - Pattern.JPG
(Creating a paper pattern and carefully aligning the cut so that I can re-use the attach hole locations)

Once I had the paper patterns cut out, I took them over to the plane and made the final adjustments so I had the fit exactly like I wanted it. Far easier to cut paper than to cut aluminum. I then transferred the patterns over to the aluminum sheet, cut each new heel plate out, drilled the holes, and filed the edges smooth. They fit perfectly.
Heel Plates - After.JPG
(New heel plates in place, ready to be secured)

While this was just a side-project to use up some left-over aluminum, with just an extra hour or two of work I was able to check off yet another small lingering to-do item in the long story of 62C.
Brian
1950 170A
N5762C s/n 19716
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cessna170bdriver
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Re: New Panel Overlay - A Work In Progress

Post by cessna170bdriver »

Brian, I’ll be quite interested to see how the aluminum heel plates hold up under use. The ones that came to me in my 1955 B-model were a light gauge stainless steel and held up quite well under 1800 hours of use and 32 years of annual removal and replacement. They got misplaced during the rebuild and the rebuilder replaced them with ones he fabricated out of at least twice as heavy gauge material as required. I’d like to replace them with lighter ones but I’m not looking forward to cutting and rolling edges on stainless.
Miles

“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
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brian.olson
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Re: New Panel Overlay - A Work In Progress

Post by brian.olson »

Miles - a quick in-use update for you. I have around 15-ish hours on the new heel plates and they are still working out well. I wouldn't consider that a long-term or heavy-use review, but my initial impressions are that they are going to hold up well. Additionally, while I planned to roll the edges I've left them un-rolled (albiet filed) and they interface with the carpet very well; no issues there. My longer-term concern will be to see how long the material resists deformation after several years of use. The new plates are definitely thicker than the old ones - which were deformed from use - but still thin enough that I was able to easily cut them with snips.
Brian
1950 170A
N5762C s/n 19716
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