Aileron Progress

There's something about announcing that you're building an airplane that immediately makes a million things pop up to take your time.  Over the past month and half, I have snuck away here and there to make progress on the ailerons. The challenge is to get a long, consistent bend without a wavy surface and without breaking the bank.

Take 1  - Hit it with a Hammer

I started by trying to bend them by hand using a rubber mallet, a board, and an 8' long 3" angel bolted to the bench as an anvil; but that resulted in scrap metal (at 91" long, that's more aluminum than I prefer to waste).  Not that others couldn't do it, but it is just not a skill that I have mastered.

Take 2 - Build a Brake to "Save money"

Next, I decided to build a bending brake using some plans I found online.  Overall, I think it would work fine, but one of my angles has a bow in it, and I do not have the talent or the tools to straighten it.  This ended up costing at least $150 when all was said and done.  I'll keep it, but without spending more money on it, it just isn't up to the task of making airplane parts with that bow in it.  Here's the brake I made.

Take 3 (Recommended) - Rent a Brake

This one is a big hit on the Thatcher Yahoo Group, so I should've started here.  I rented an 8' brake for about $75 for the day from Home Depot and a U-haul truck for under $50.  I ended up with nice straight bends for less than the cost of the homemade brake.


I was able to move this by myself, but just barely.


It is hard to see it here, but you can see that I used two long strips of sacrificial aluminum (from my previous failed attempts) to make a larger radius on the bends.  Just cut two 8' long and 2" wide strips of .020, and bend them in the brake together.  Then keep them in the brake when you bend the actual airplane parts.  I was happy with the results.  The tape kept those pieces from moving in between bends.



Here is the end result.  I made two ailerons, two trailing edges for the wing tips and some new wing tip spars in just a few hours.  I WANT ONE OF THESE BRAKES!


The bends a little closer up.



To get the ailerons to take the final form, I had to manually manipulate the bends to make the two ends touch.  I did a lot of this with my hands, a couple pieces of plywood, and a mallet.

At first, I did not make the bends tight enough, and I ended up with some "oil-canning".  Here is a video of the problem.  Making the bends a little tighter fixed this.

And here it is next tot he wing with the ribs in place and some masking tape holding things in place.  Next step is to measure and cut the hinges so I can mark the rivet holes and drill them.

Merry Christmas!

Right Wing Tip Cont (Ribs)

I made both wing tip ribs and right wing tip center rib.  Looks cool, but I really need to find a way to bend my ailerons.  I think a guy at work might be able to help because he knows someone with a shop and a 10' brake.  In the meantime, I'm going to try to produce all of the left wing ribs and center ribs over the weekend while I wait.  I don't want to rush things, but I think "analysis paralysis" is slowing me down too much.

The parts in these pics are just sitting in place.  No rivets or holes yet, but cool to see it come together.  The reality of a one car garage is setting in!

Starting the Right Wing Tip

I received some more rolls of sheet metal and decided to cut some pieces out to save space in the garage.  I also started to make the wing tip parts.  I bent the right main tip spar by clamping it between a board and an 8' long piece of 3"x3" 1/4" angle steel attached to the workbench as recommended by Dave in the build manual.  Placing a board between the hammer and the part being bent seems to really clean up the bend over striking the part itself.  I'll post some pictures/video of the process if it keeps working for me.



I also received the wing and elevator tips from Earnest Martin today.  I really wanted to try to make these, but his parts look great, and I really like that it gets me that much closer to flying.



Time to watch the tribe beat the cubs in game 2!  Go tribe (but seriously, who hates the Cubs?)!

Fuselage Bulkheads Arrive

Hurricane Matthew slowed things down this week, but I did receive the bulkheads that I ordered from Greg Westberry.  I'll do a full review of these and the tail kit when I get to them, but there's a lot of wing left to build yet!  Looks like they make nice quality parts though.

Leading Edge, Lower Wing Skins and Rear Spar

It's been a while since I've posted, but I've been busy on the right wing.

Since my last post, I was able to:

• Add nylon hose for tip lights or maybe a leading edge landing light down the road
• Drill and rivet the leading edge
• Mount the lower wing skins
• Fabricate and rivet the rear spar and reinforcement
• Cut one of the top skins and mark drill holes on it

Leading Edge

The leading edge was a little difficult to work with. but I was able to bend it and attach it on my own.  For some reason I had a hard time picking where to space the rivets.  I just looked at pictures and counted how many rivets other builders had, and that seemed to help.  You can see the lines on the sheet in the image below.   This picture also show the hose I added to run wires through if I want to add lighting later.  I kept it toward the leading edge so it would be easier to add a landing light in the leading edge if I ever felt like it.

I drilled the skins, and marked the center line down the rib to help me align the rib with the hole when matching drilling.  In the picture above, you can see the holes drilled and the center line on the first rib.

Clamping a 2x4 at the base of the leading edge helped to hold it in place.  Then I could add one on the other side to test the fit.  I used the broom handle to align the ribs with the holes I drilled in the skins.  Seemed to work well.

Everything riveted in place.  I left two holes on the top and bottom of the wing root rib empty to maybe use as the screw holes for the wing gap fairing that will need to be added later.  I haven't thought through that whole process yet, but you can see the missing rivets below.  Also, don't forget to leave the out board rib alone (no rivets) so you can attach the wing tips.  I got "rivet happy" and had to drill some out.

Trailing Section

So this is a little bit out of order.  I actually drilled and test fit the rear ribs before attaching the leading edge skin.  Rivets are pretty permanent, so it seemed safer (I don't think it makes much of a difference).

The Dremel with a flexible extension is almost a requirement when drilling the ribs if you want to get a nice perpendicular hole.  

I used the rib alignment jig mentioned in the build manual (make sure your tooling holes on the ribs are all in the same place.  If they are not 100% perfect, you might want to try the method I used to align the nose ribs in an earlier post).

Test fitting the lower wing skins...

Wing skins bent.  I bent them over the straightest 2x4 I found.  Worked okay, but I bought the recommended 3" steel angle since for bends.

More test fitting above, and below with the rear spar (1x1 angle 1/8" thick).

I marked and drilled the lower skins.  Much easier since there is no fluting on the bottom of the rib flanges.  The two bottom skins overlap each other.  Since the wing tip is higher than the wing root once installed on the plan, I decided to make the outboard panel overlap the root panel.  My thought was to keep water out of the wing when tied down.  

Hole Duplicator
For the overlapping section, I made a hole duplicator so that both skins and the wing rib would all be match drilled.  It is a very easy tool to make and uses two 42 blind rivets and one solid rivet from the spars.  Worked great.  Just match drill the lower skin and the rib, then use the duplicator by sticking the solid rivet in the hole and drill the top skin.   Now all three pieces are perfectly match drilled.

To make one...Drill two matched holes in two .040 scrap pieces for BSBS-42 rivets.  Rivet the pieces together.  Then drill a third #30 hole in the opposite end once they are riveted together.  Add a 470-4-7 rivet as a drill guide in the third hole.  Here are some pics.

 

Below is the riveted wing so far.  I should have done the top skin first as the manual recommends.  My wing is very straight, but I can see how you would use the lower skin to adjust any warping you have.   I'll do the left wing in that order.  

Drilling and riveting the lower spar (again, manual is right.  You should do this last).  That's a lot of holes!

Rear Spar

Not much here to show.  Just drilling a lot of holes.  Make sure your wing is straight and level so you don't add any warping.

Rear spar reinforcement.  Bolt direction is opposite of plans.  I'm not sure if I'll regret this later, but I saw others do it this way on planes that have been flying for a while.  

Test fitting the top skins.  The blue tape is to stop me from riveting what I should not.  I tend to get an itchy trigger finger once I get going.

Feeling a'ri' (as they say in Jamaica)!

Key West and Getting Married

I'm still here.  I have some catching up to do, but we ran off to Key West and got engaged.  Right wing is coming along nicely with updates coming soon!

Nose Rib Riveting and Wing Skins

Over the past two days, I riveted the nose ribs to the spar and bent the leading edge of the skin.  I managed to put a wrinkle in one leading edge.  So I had to make a new one.  While I was at it, I cut most of the main wing skins (not the tips yet).

I measured the plans and drew two straight lines down the workbench to set the proper rib position from the spar.  I thought this was a really easy way to ensure they were all even.

Here you can see the spar and the aluminum angle for spacing.  The wood blocks are screwed down with two blocks on the back side too.


Here is a rib held in place for alignment.


Here are several ribs in place with drilled holes and 3/32 clecos.


Here is the finished piece (you can see the two lines I drew on the workbench pretty clearly in this picture.



I didn't get a picture of the bent skin, but I used Dave's method of pressing it down with a 2x4 after some encouragement from the Yahoo Group.  It was pretty easy.  The first one was wrinkled because I rushed it, and not because of the process.

More Materials and Right Rear Ribs

I came home to this today!  Aircraft Spruce and Greg Westberry delivered on the same day.



Greg Westberry delivered the tail kit.  It is the big box in the back.  I'm going to do a full write up on the kit when I get to the tail for anyone on the fence about ordering the kit.  For now, it will stay in the box (that's so hard to do!).


The other boxes are 2 more 4x12 sheets of .020 6061-T6 and one sheet of .032 6061-T6.  I also have my piano hinge now and all of my blind rivets and the bushings (etc.) for the center section plus some other miscellaneous parts.  The big bag in the back is 4,500 blind rivets.  That's a lot of holes to drill!

All of this fired me up to bend some metal, so I made the rear ribs over the form blocks tonight.  I had already made the forms and blanks.  Here's a shot of the pieces temporarily clamped together.   Cool!

Rear Wing Rib Blanks

Work and and social obligations (read as: "hangovers") kept me from building this weekend. An interview with Charlie Becker (EAA) reminded me that even 10-15 minutes here and there helps to see the project through. I did about 30 minutes today drilling and cutting my rear rib blanks. Its good to be another couple steps closer with 4 rib blanks.  If I do that everyday, I think it will make a big difference on the project.

Below I drilled the inside corners so there are not any sharp corners when I make the cuts.



Then I used the Andy Shears to cut all four blanks by hand.  It's pretty quick.  Also, the rib blanks do not have to be exactly the same (that should be the goal, of course).  It is the form block that ultimately makes the shape the same for each rib.  If you're flanges are half a millimeter different because of your cuts, that really won't be an issue.  So don't feel pressured to use the router setup if you want to save a little money.  For me, I just like to be able to hear the radio instead of a router.

Making Ribs

I mounted the aluminum angle brackets on the right wing and started making the ribs this weekend.  I decided to primer the brackets like I did for the other spar pieces.  I am not going to primer the ribs.

For making the ribs, I followed the 6 part video series on the EAA website for making aluminum ribs.  

Here is a shot down the right spar with the half inch holes now drilled too.  

Here is a closeup of a leading edge rib bracket made from 3/4" .062 aluminum with AN3-6A bolts (The bolt size varies depending on the location along the spar) holding it in place.  I had to do some digging, but was able to find that the AN4 bolts should be torqued to 50-70 inch lbs of force (notice that is inch lbs and not foot lbs.  Big difference!).  There is a really great write up here that I printed for future reference in the shop.

I didn't take a lot of pictures of the rib forming process since I'm basically following the EAA video.  In the far background you can see my rib forming blocks.  One thing to keep in mind is to mark the fluting positions on your ribs.  You need to do that so your rivets fall in between them when you attach the skins.  

I'm fluting my ribs with this tool. It works fine.  I kind of wish it made smaller flutes though.

To flange the lightening holes, I'm using the process described by Dave Thatcher in the build manual.  It doesn't require an expensive die and is easily duplicated if needed.  You just use the fly cutter that cuts the lightening holes in aluminum.  You cut halfway from one side of the block, then flip it over and cut halfway from the other side.  You end up with a die like the one below that you place into the forming block to force the flange.  I've been using a hammer, but I might try the arbor press I used for riveting next.