Cost to Metalize

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6896
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Re: Cost to Metalize

Post by 6896 »

Some photos of the fuel cell bay cover
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6896
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Re: Cost to Metalize

Post by 6896 »

Fuel cell bay drain doubler inside view and leading edge landing light, which is another Skycraft STC
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8362
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Re: Cost to Metalize

Post by 8362 »

Nice work.

Can I ask why you chose metal over fabric?
That plane is going to way too nice not to hanger!

Matt
6896
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Re: Cost to Metalize

Post by 6896 »

My C140 project came with a metallized wing, so I restored it to the same configuration, but with new aluminum. The original metal skins had defects and some of the nose ribs were cracked, so we doubled them up to take care of all of the underlying issues that were not visible until we removed the skins. I stayed with metal skins for durability and weathering, albeit at the expense of increased weight.
8362
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Re: Cost to Metalize

Post by 8362 »

Thank for the information. Good luck with your plane.
Matt
6896
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Re: Cost to Metalize

Post by 6896 »

Thanks Matt
4945
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Re: Cost to Metalize

Post by 4945 »

6896 wrote: Wed Nov 21, 2018 8:19 pm I have hundreds of photos along the way showing the step by step process. Applying the skins is tricky in that you have to roll the skin spanwise and rivet a little at a time to not get boxed out where you can't use a bucking bar. We did well in this regard and had to use very few NAS1398AD4 or Cherrymax rivets. Most of the rivets are AN470AD3 type, but you may need a collection of oversized rivets too if your project is like mine with sloppy holes that were redrilled. I spent a fair amount of time sourcing oversized rivets in both the Cherrymax and solid varieties. You'll also need to grind some custom bucking bars to rivet the skins to the spars to work around the bulbed angles. My father and I became pretty good at riveting since there were so many rivets to form.

It's a great experience to do this, but be patient and careful if you attempt it and hopefully you have a good helper.

Tony
Hi Tony,

How did you rivet the wingtips? I have a 120 with metalized wings by Met-Co-Air with a hole corroded in the bottom of the starboard wingtip. I need to remove it to repair it. Drilling out the rivets is easy. I don't want to take it off until I have a plan to put it back on without using dozens of CherryMax rivets.

Gary
6896
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Re: Cost to Metalize

Post by 6896 »

In lieu of blind riveting, I used #4-40 stainless steel truss head machine screws with nut plates onto an aluminum strip, which is in turn flush riveted to the inside of the wing tip. I had to partition up the nut plate strips to accommodate the tapered trailing edge. As you know, unlike later Cessnas, our wingtips fit inside the wing skins for the metal wing STC. Later Cessnas used screws for their wingtips.

The #4-40 truss head is not noticeably larger than a AN470AD-3 or AN470AD-4 rivet head from a short distance.

I also used #10-32 nut plates instead of nuts for the four standard #10-32 truss head screws that originally held the tip to the wing for fabric covering.

My approach is a bit heavier of course, but a removable tip allows access to wiring, etc. if needed.

See photos.
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Wingtip hanging showing 4-40 nutplates.JPG
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Primed nutplate strips for tip.JPG
Primed nutplate strips for tip.JPG (186.2 KiB) Viewed 2953 times
Riveting nutplates onto alum strip for tip.JPG
Riveting nutplates onto alum strip for tip.JPG (192.38 KiB) Viewed 2953 times
6896
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Re: Cost to Metalize

Post by 6896 »

More photos
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Tip Fitcheck.JPG
Tip Fitcheck.JPG (124.45 KiB) Viewed 2953 times
10-32 nutplates tip.JPG
10-32 nutplates tip.JPG (121.38 KiB) Viewed 2953 times
Close up inside wingtip with 4-40 nutplates.JPG
Close up inside wingtip with 4-40 nutplates.JPG (121.48 KiB) Viewed 2953 times
6896
Posts: 105
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Re: Cost to Metalize

Post by 6896 »

More photos.
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Wingtip installed with temp handle to move.JPG
Wingtip installed with temp handle to move.JPG (130.27 KiB) Viewed 2953 times
Wing End View before tip.JPG
Wing End View before tip.JPG (162.82 KiB) Viewed 2953 times
Tip Fitcheck.JPG
Tip Fitcheck.JPG (124.45 KiB) Viewed 2953 times
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