Ch 19 Wings, Alierons

Plans have the builder use a phenolic block with a hole in it to guide the aileron pushrod, CS150. I can tell you these tend to wear and can be sloppy, yep thats what I have in my already flying plane. I’m going to use a ‘plastic’ bearing instead. The part is an IGUS EFOM-16 ( from Treotham P/L in Australia )

You can see these in Pic 1 where I’ve begun making a housing for them out of 2024T3 .063″ I made a friction fit, partly because I want to index the part so it cannot move and secondly to have zero air leaking into the wing at this point.

Pic 2 shows my plates made up with nutplates, alodined and ready to fit. Just over an ounce for the two. You can see a piece of tube through one of the bearings. I’ve had this machined at one end to fit the pushrod and the other end is a metric size as this size IGUS thing insists on a different measuring system to the rest of the plane.

Pic 3 has the bearing holder floxed in place. I drilled 3 tiny holes so I could pin it while the epoxy sets. The bolts and greased up so the nut plates don’t fill with flox. The plates are not perfectly shaped visually but they do fit nicely.

IGUS fitting

Shaped bearing holder

Floxing in place

I was unhappy with the rudder fit so time for a ‘revision’. One wing was ok but the other had the rudder displaced slightly from the flat surface of the winglet. I could just use filler to fix this OR pull two hinges off, add a few plies of BID and reset them as you see in pics 1 & 2. It took a few days, a a few tries but all is good now and perfectly in line.

Next up was the aileron travel. This needs to be 2.1″ +/- 0.3″ at the inboard edge and I was at 1.8″. It looks like I’d placed the clickbonds about 0.1″ too high and this was preventing the hinge from closing. I trimmed all the clickbonds which fixed one wing. The other also needed a regular rivet replaced with a countersunk one. Talk about fine tolerances. All good. Move on.

Hinge spacers

Rehinge

Aileron range

The last 5 days I’ve been doing one clickbond per wing as needed to get the 14 of them done. Each time I had to get the aileron off carefully as each time the hinge tends to stick no matter what. I did get them all sorted out with zero damage, it just takes a while.

Today was more like it. I sanded the six hinge locations down to the clickbond and preped the surface for one ply of lightweight cloth as I did in my testing. Pics 1 & 2 show this. Some of them were down to the metal and others I had them just a touch deeper. I’m confident it will work out with minimum filler to give a smooth result.

Pic three shows the cloth wetted out, in place and a bit of peel ply on top. All the click bonds are done now and the ailerons move freely. I need to check it they are getting the required range of movement next.

Sanded flush

More sanding and prep

1 ply on top and peel ply

Aileron gaps should be between .08″ and .2″. I’ve gone for .10″ all around after preserving the minimum gaps until now. The idea of that was if the ailerons moved I still had room to get it right. Yeap that all worked out and now they move nicely. Took quite a while of careful sanding and refitting the ailerons.

Pic 3 shows a few more clickbonds in place. I’m doing one on each wing per day. Thats so I keep everything in line and so that I only have one nut and thread to unstick. Whatever happens a little glue gets in between things. I’d rather that than any dry areas.

OK aileron weights came in at 3lb 11.7 oz and 3lb 12.8oz. 0.9oz difference which is explainable given I had one extra filller plate on one side. Pretty minor stuff. OK so IF I used mild steel rod weight would have been 43 ounces not 20 ozs. Now if I’d used plans size rod it would be a lot less again.

That said lets say my aileron weighs are estimated +23oz over what I have.plus the universal at 5.2 oz so I get 5lbs 7oz with the heavy rob compared to the Mike Mellvill weights of 5lb 2oz.

Given the heavier rod being more than 5oz I’m in an excellent place with aileron weights.

Correct gaps

Weigh in

More clickbonds

With the screws in place and the ailerons lined up I just have to install the clickbonds now. All that extra padding on the inside has that hinge area very secure and I’m happy about slightly inlaying the clickbonds with my dremel.

I’m not going for perfectly flush. I’m sure a tiny bit of filler will happen later when the wings are finished. That said I don’t need a big bump either. I’m going to flox these in and then in a separate cure cycle add a thin ply of glass on top. I’ve tested this method with success.

Pic 1 shows a trial fitting. You might notice 4 small holes which I’ve added to every clickbond so the flox can grab them to prevent turning. My test showed this isn’t really necessary but being holes they truly weigh nothing! …and add strength to the bond.

I’m just doing one or two of these at a time. After cure you have to get the hinges off and its a struggle no matter how careful you are with excess flox and release tape.

Pics 2 & 3 shows this. While its a full day cure cycle having two wings is keeping me busy. I’m sure if I did all the clickbonds at once it would be no fun getting the ailerons off.

Inlayed clickbond

Floxed in

Another one

A few days here again. First up I found that the aileron while exactly now matching the TE of the wing was slightly out of line front and back. All I need are a few ply of BID at the hinges to space things out. Yeap …sorted that one. You can see in Pic1 some additional plies going down and pic 2 shows that I am now inline top and bottom. Yippeee

Next up was drilling out the clico holes up to the size of screws. Of course I’m not using screws but I’m going one step at a time continually checking that its all still correct. Wish I was this careful with the rudders…. which is why I’m now so careful. Yes I’ll get back to those rudders… let me get the ailerons done OK?

Extra inside plies

Exactly right both sides

Setup screws

Finally happy with the aileron side hinges relative to the wing. I used the same method as the left wing. Get it all happy and just stuff 5 mt glue in the hinges. I was much smarter this time with the glue and it was really easy to get off later while things were still positioned. Maybe its true that the second airplane is easier to build.

Pic 2 is the current workshop setup where I have both wings on the ground and the fuselage in the middle. I’m stepping over stuff all day. Good workout for the knees.

Pic 3 is the inboard hinge riveted on. You can see my spacer behind it. Those hinges are in line now. Whatever it takes…

Reset holes in place and glued

The aileron factory

Riveted

A lot has gone on here over several days. Pic 1 has the left aileron in place with clecos and I’m checking that the skins are exactly equal on both sides. Well they are close but I can fix it later so they are perfect before I put the clickbonds in.

Meanwhile I’m on the right wing setting the aileron hinges in place. I line them up with the straight edge and hot glue. Then it was a check with the aileron in place to see if it was perfectly in line at the TE. Not so. I went through a process of lowering the hinges about .05″ to get it spot on. That takes some very careful sanding and working with the levels and rechecking.

When I was happy I again checked that the hinges now hot glued in place with the aileron in position was correct. Haaa just like the other one the hinges are somehow not perfectly in line and there is a tiny gap.

Pic three shows a thin piece of 2024T3 that was just right in place. Alodine and 1 ply of BID as usual. Less than .5gram weight penalty is worth it to get exactly in line. I have no idea how other people get things right the first time. Please email me to explain.

Left side alignment check

Right hinge levels

Improving levels

I spent a while sorting out the rivet drill patterns and drilling them out, checking the sizes and so on. I like a number #30 drill for 1/8″ but start at 1/16″ and go up.

Next up was popping off the hinges as you see in pic1. You might note there wasn’t that much 5 mt glue and it did the job. Pic 2 shows it all cleaned up and the surfaces dulled. I mixed some pure epoxy and coated the parts after a good clean. Then added flox per plans and secured them in place with MSP-43 cherry rivets. (Pic 3) Oh yeah, you can see the aileron rib in this shot as well. That’s just a bit of tape protecting the A10 tube for now.

I’ll recheck that things are in line tomorrow and then I can move on to replacing the clicos with click bonds… or I might just start on the other aileron. Guess its my call.

Hinge off with residue glue

Cleaned up

Floxed and riveted

Now to set the aileron hinges on the ailerons in the right place. I thought the sharpened blade was the go but the suggestion from a certain Mr Wood to use foam came into play as in pic one. Just the right amount forces the hinge to close on the aileron when you put the aileron in place on the wing. I also used my blades to check that the hinges were hard up against the hinge bases.

The plans have you somehow stick some bondo in there and get the whole catastrophe lined up perfectly and un-moving while it all sets. With my sticks and clamps and hot glue I got the aileron lined up and thought… good job.

Instead of moving anything I just stuck 5mt glue in the hinges to hold it all together. When it cured I removed the clecos and had my hinges in place. Then I added more hot glue around the hinge edges to hold them down even more …oh and spent about an hour removing bits of glue and the hinge pins and the other half of the hinges.

Yes seems like a clumsy way to do things BUT… I have the aileron right where I want it.

Foam ‘spring’ spaces

Gap checking

Glued hinges exactly in place

Just a small hiccup here. I’d gone to great lengths to ensure the hinge bases on the ailerons were exactly in line. It turns out that great care and attention to every detail or even the measurements made in good faith account for nothing in the light of facts. Perhaps the nice heavy weights I used deformed the aileron.

The result was that the third or outboard hinge was slightly low. I found some nice 5005H34 aluminium sheet. I would have used something else but this was the right thickness. I made up a piece, taped it in place and all was right with the world again. You can see it in Pic1. Of course I had to then clean it up, alodine it, let it dry and then flox it to the prepared glass at the hinge base. Next up was a ply of BID over the top and a weighted cure. All done as you see in Pic 2

Pic 3 might be hard to understand but it is the aileron hinge in place with a bit of sharpened hacksaw blade pushing it home so I can check for a gap. All again is good.

Add on piece

Glassed in place

Gap check

This step is lining up the hinges on the wing side for the ailerons. I elected to just use clicos rather than drill out the full size hole. You never know if you might get something wrong and need to re drill so the smallest hole size is best to start with. Of yeah and I did finish off the aileron end ribs yesterday too.

The fun technique I used was to get the areas in between the hinges level and then clamp and hot glue a box straight edge to this level surface. Next up reach into the alieron rib cove and hold the hinge hard up against the straight edge. From here I easily hot glued the hinge in place and then the same with the other two. Bingo, hinges in line.

I drilled out the hinge holes previously marked out, and stood back proud of myself for being clever. Then I checked the aileron in place only to find it was slightly too high and I needed to loose some material on the wing side. Yep, good thing those holes were small for the clicos.

So I redressed the aileron edges on the wing side until a perfect fit was obtainable, set it all up again and re-drilled my holes having moved them on the wing side .05″ to .10″ It seemed to work out again. I think I’ll do more on this side before doing the other wing. One set of mistakes is easier to fix than two. The gaps are still pretty small for setting up the internal side of the hinge. More fun tomorrow on that.

Hinges in line

Drilling out the minimum

Secured in place