Chapter 20 – Lower Winglets

Chapter 20 – Lower Winglets

30 May 2013 — Also, although I’m not 100% one way or the other on whether I’ll have lower winglets installed or not on my bird (leaning more pro vs against), I would like an upgraded look compared to the stock look.  I don’t necessarily abhor the stock lower winglets (my buddy Marco growns even at the mention of them, and threatens constant Unfriending on Facebook if I install them! ha!).  Anyway, I’ve started my research and am flirting with a redesign on my lower winglets.

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31 May 2013 — I’ve been figuring out & playing with some initial design changes on the lower winglet.  I came up with this below.  Although I won’t be using this design, I thought I would post a pic just to show some of the design processes I’m working through.

Chap 20 - Testing lower winglet design

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4 June 2013 Over the last few days I had researched a lot of different lower winglet designs & tried a number of different cutouts until I found the one I finally liked.  There is no drastic difference from the original stock plans lower winglet compared to my new design, which is really just a stock look but with a lower profile.

Chap 20 - Lower winglet

My finalized version of the lower winglet is 1.8 inches shorter top to bottom (or narrower if you look at the profile) than the stock plans version.  Also, the angle starting from the aft/trailing edge and moving forward to intersect the flat looking bottom line is moved significantly forward than the plans version.  These are essentially the “Mini-me” lower winglets of the plans version.  I cut out the new design with white poster board.

With my new winglet design in hand, it was time to get to work.  I started with the Left lower winglet, placing the template on top of the winglet and tracing out the template with a Sharpie.  I then simply cut along the marked line as close to 90° to both sides of the winglet as I could get it.

Chap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower winglet

 

 

 

 

 

 

Chap 20 - Lower winglet

Chap 20 - Lower winglet

Once I got the basic shape cut out, I then had to hand sand the new lower winglet to its final form.  I used the unmodified Right lower winglet as a general guide to figure out the shape & rounded contour of its edge all the away around the bottom outline of the winglet.

Chap 20 - Lower winglet

Chap 20 - Lower winglet

Chap 20 - Lower wingletChap 20 - Lower winglet

Once I was 95% complete with the Left lower winglet, I started on the Right winglet.

Chap 20 - Lower wingletsChap 20 - Lower winglets

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5 June 2013 —  I started out by finishing the shaping of the Right lower winglet.

I then shaped foam bases (from the original foam that the winglets were cut from & encased in when they were shipped to me) to mount the winglets to during glassing so that they would maintain their shape.  I screwed the foam bases to the work bench with 3 wood screws.

Chap 20 - Lower winglet

I mounted the lower winglets to the foam bases using 5-min glue & weighed them down while curing.

Chap 20 - Lower winglet

With the winglets mounted to the bases, I prepped them for glassing.  I vacuumed the winglets & tacked in a 1″ peel ply strip along the TEs.

Chap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower winglets

I the micro’d the foam, working on only one winglet at a time.

Chap 20 - Lower winglet

I glassed each winglet using 2-plies of UNI at ±30° bias.

Chap 20 - Lower winglet

Chap 20 - Lower winglet

I then peel plied the edges after laying up the glass plies.

Chap 20 - Lower wingletChap 20 - Lower winglets

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6 June 2013 — I razor trimmed the glass on my lower winglets and then pulled the peel ply off.

Chap 20 - Lower wingletsChap 20 - Lower winglets

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8 June 2013 — I started off today by sanding the lower winglets’ leading, bottom & trailing edges.  I sanded the TE trough and filled it with dry micro.

Chap 20 - Lower winglet

I cut off the lower winglets’ fish tail & removed the peel ply & nails, and then sanded to shape.

Chap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower winglet

I transferred the cut UNI from my cutting table in my downstairs workshop to the garage.

I sanded the LE, bottom edge & TE for a smooth transition when I glassed the second side of the winglets.

Chap 20 - Lower winglets

I scrounged around & found 4 scrap pieces of wood as spacers & mounted them to the workbench with bondo.

Chap 20 - Lower winglet build

I then bondo’d the 2 winglets down to the workbench, using the scrap wedges to prop up the narrower bottom edges of the winglets so I had good solid platform at the appropriate angle to glass each winglet.  It also gave me clearance to wrap the glass from Side B for a 2 inch overlap onto the LE & bottom edges of the Side A glass.

I then weighed the winglets down while they cured.

Chap 20 - Lower wingletChap 20 - Lower winglet

Chap 20 - Lower wingletChap 20 - Lower winglet

I used dry micro to fill in the plugs that were extricated from the foam when it was 5-min glued down to secure when I had glassed Side A.

Chap 20 - Lower winglets

I used micropaste with a little flox mixed in for my usual LE foam prep/fill.  Then microslurried the “field” on one winglets & glassed the 2-ply UNI layups (again, sequentially & one at a time).  Since I didn’t want to waste glass, on the Left lower winglet I started by laying up 2-pieces of UNI butted up against each other for the first layer, then covered that with the second ply which covered the entire winglet.  I then left the winglets to cure.

Chap 20 - Lower wingletChap 20 - Lower winglet

Chap 20 - Lower winglets

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9 June 2013 — I started today by popping the lower winglets off of the wood blocks that they were bondo’d to.  Then I chiseled a bunch of cured bondo off the winglet surfaces.

Chap 20 - Lower wingletChap 20 - Lower wingletChap 20 - Lower winglet

I then marked, cut & sanded the TE of both lower winglets.

Chap 20 - Lower wingletChap 20 - Lower winglet

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16 June 2013 — After snapping some pics of the cowling, I then sanded the Left & Right elevators and the Left & Right lower winglets, then cleaned them up, vacuumed up the dust and took them down to the basement in preparation for getting packed up, shipped off and stored for a year.

Chap 20 - Lower wingletChap 20 - Lower winglet

Once down in the basement, I took another opportunity to check the fit, finish & look of the lower winglets “mounted” to the upper winglets:

Chap 20 - Upper/lower winglets test fitChap 20 - Upper/lower winglets test fitChap 20 - Upper/lower winglets test fitChap 20 - Upper/lower winglets test fitChap 20 - Upper/lower winglets test fitChap 20 - Upper/lower winglets test fit

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Recent Posts

Project Update

Hi Folks,

Months ago I made a goal to try my best to get this bird done before the Rough River fly-in.  Yes, a crazy goal… but I knew it would keep me working on the plane full bore.  So much of these builds are like running a marathon… mental motivation.  As in staying motivated.  

When it was clearly obvious that I wasn’t going to make Rough River, I took a break for almost a week to head back up to the DC area to simply relax and visit friends.  Upon my return I’ve been getting some personal things done and am really just getting back into the build.

With the fuselage still inverted I’ve knocked out nearly all of the “micro” (West 410 + micro) finishing on the bottom surfaces of the airplane and the subsequent epoxy wipes ala the Corey Bird finishing method.

Within days I expect to be be diving into knocking out the main gear leg-to-fuselage interface fairings as well.

Concurrent with completing the gear fairings I plan on doing a fair amount of priming and painting on the bottom side of the bird as well.

Yep, I expect this bird to be inverted for another 2-3 weeks (ha!) before it gets flipped back upright to close out the strakes with the top skin install.

After the top strakes it will be on to the winglet/rudder install (Chapter 20).  Then engine and top cowling install, topside finish and prime/paint.

 

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  5. Chapter 23/25 – Flox & Primer! Leave a reply
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