Ch 12 Canard Installation

Date:  08-30-2018

Number of Hours:  12

Manual Reference:  no ref

Over several days and many cure cycles I’m slowly making progress on sealing this canard. The cold air that comes in from gaps I have experienced over many flights, this airplane will have the minimum possible air leaks. It IS worth extra effort here.

Here we have the top half of one of my phenolic bearings. Pretty messy? Sure, I need to get the top half connected to the canard and the bottom half stays on the fuselage.  I know it will take a few goes. For a start, one of them fell off and I had to go again for yet another cure cycle.

A bottom half here and they are starting to stay put and get filled in.

This top half is starting to look right. Now I have the torque tube sealed of course I still need some sort of close seal for when the canard comes off and goes back on. I found I needed to file a flat area, seal that with tape and reinstall the canard and get filler up to this area too.

After another cure cycle and the gaps are really minimal now and the canard can be removed and replaced fairly easily.

Now we are getting really close. These gaps are the minimal I was seeking. I can get a little better but its approaching a very close seal.

I’m almost happy with this!

While all the torque tube sealing was going on I had a massive gap at the rear of the canard. If the canard cover was not removable if wouldn’t have been an issue. As it is…. I needed a good rear seal too.

The first step was to extend the rear of the canard about F28 I think? Anyway extend this down with a piece of fitted foam. Of course I had to glass both sides with a ply of BID with a good inch overlap.

Here’s the inside, peel plied of course.

I went to some trouble to also get a front seal, but it still had tiny gaps. So I had to add to that front seal with an underneath seal as you see above.

Now my rear wall seal still had a gap too. I’ve trimmed that wall and added yet another few plies of BID under the canard joining into the wall. That all may not make sense. I hope the picture above clarifies it. I’ve added seals to the front and back of the canard that also curl under the canard so it really does seal! Thats four separate operations here. I think we are good now.

Meanwhile the canard cover needed extending.

Yes the canard cover had those gaps at the sides from when I raised things for a bigger instrument panel. Hey, its just a bit more work.

Meanwhile with the canard cover off I realised that some of it was still bare foam so that got a ply of BID. While I was at it I reinforced the side fill areas.

Here we are after the cure and it still needs work. I added some flox to that daggy front corner tonight and it will need more trimming later and maybe another fill to get the gaps down to nothing. I’ll keep at it. We are getting closer.

Date:  08-26-2018

Number of Hours:  12

Manual Reference:  no ref

This is all about sealing the canard at the fuselage so I don’t get nasty cold air into the cockpit when I don’t want it. If I want air, I will use the air vents. Leaks are not allowed.

The first step was to install the elevators and assess what needs to be done.

Elevators need elevator pins installed. I have been dreading this as it was really tough to get them out last time. What was I worried about? It only took FIVE hours to get the first pin in,    …and there are two pins, one per elevator. Secrets are that I sanded down, or smoothed the pins first with 800 grit wet and dry paper. Then I covered it in Vaseline and packed the hinges with the same. This helped. I also drilled a wider access area in the Cozy Girls offsets just where the pin aligns. That helped too. I used vice-grips as above with a lot of tape wrapped around the pin AND all that green rag. This helped. I got it done.

I made problems for myself with a cascading series of issues created by one small modification. Why do I keep doing this?  I went from the plans upper pin locators to AN bolts instead. Then I realised I needed to access the bolt head at the canard because of future avionics being in the way. So I had to re-locate the nut plates for the bolts from the front to the rear. This now meant that my canard cover had to be removable. This also meant that I have a LOT of air gaps that need sorting out.  As a final insult to self… I raised the nose angle to allow a higher instrument panel. This caused great gaps in the canard cover that previously was a perfect fit.

A fresh issue is the gap at the fuselage for the offset torque tube. It rotates in a circle unlike the plans elliptical motion that I cut the fuselage for some years ago. Now I just have a round area to plug.

There are giant gaps at the back and the front of the canard relative to the fuselage that also need addressing.

Here’s my torque tube solution. I went to the supermarket and bought a cutting board which is made of phenolic, just like in the plans for aileron wing fitting! I also bought a 3/4″ hole saw. The same OD as our torque tube. I drilled out a hole and then very carefully cut it in half with a very thin bladed hobby saw.

Initially I wasn’t sure how to do this. I’ve gone for a doughnut  shaped fitting with the idea that it will be a really snug fit around the tube, free to rotate yet letting in the absolute minimum air.

My idea is to fit the canard and for now just micro in the bottom of the doughnut fitting. I used some hot glue to keep the top piece in place. It was quite challenging.

After cure you can see the bottom is in place now, in the exact correct place. The gaps are easily filled later.

A bit is happening here, not just a mess. I have made a bed of micro for the canard to sit on and then bolted the canard into the final position. Next I hot glued the top of my doughnut ring to the bottom half. It took a little doing. Now I’ve added micro to connect the top of the ‘ring’ to the underside of the canard without anything sticky touching the fuselage. The concept is after cure, I’ll remove the hot glue and the canard should come off with a perfectly located bearing ring of phenolic in place. Half on the fuselage and half on the canard.

After this I have some filling work and I need to ensure the canard goes on easily too. This will mean a bit more filing and filling so the two halves allow easy removal and a perfect seal.

While doing the tube and bearing sealing I thought I could also seal up between the canard and the front edge of its fitting area. There is a really big gap there. I’ve gone for a three inch wide 3 ply BID to stick in the hole.

That area in front of the canard is my unattractive glass strip which I hope, after cure, will become a simple air blocking forward lip extension.

 

 

 

 

Date:  02-15-2018

Number of Hours:  5

Manual Reference:  12-1

This is a modification of the modification! Instead of a pin we have a long bolt. Now I’ve decided to reverse which end is the bolt and which the nut plate. Why, do you ask? I’m now going with a removable canard cover, I wasn’t sure before. I need to reverse the nut/bolt combination because once the instruments are in it will be very hard to get the bolt out from the IP end. So that mandated the cover being removable too.

For the one or two people following my progress there has been no post for a week or so. I’ve been working on circuit diagrams and learning enough CAD to get them into .dwg files. Just the main drawing done now and I’ve gone a bit sideways looking at external lighting and throttle switches. Its good to be back mixing a little epoxy again.

Here is our ‘before’ situation…  nut plate at the canard and bolts needed to go from the panel area. Its just not going to work.

Here we are with the nutplates removed and our long AN3 bolts good to be inserted. These are so long the curve of the canard touches them!!

Here I’ve made a couple of nutplates on aluminium to size. I have an alodyne pen so while it’s not as pretty as a dip it get the items coated quickly and easily.

Here we are all done and floxed in place. I added on ply of BID to bind the bracket to the fuselage sides. Probably the flox would have been enough, but hey I like to be tidy and added a 1.5″ square with a little peel ply at the edges. I did go to the trouble of having the canard installed for this so I’m pretty confident it is all in line.

Date:  05-25-2016

Number of Hours:  5

Manual Reference:  12-1

After the holes have been drilled out and the tubes fitted I needed to secure the nutplate for fixing. I also found that one tab was just slightly away from F22 so I added a ply of BID to its back.

Anyway I have the nice Garolite G10 and secured a couple of nut plates to pieces. You can see I countersunk the holes and made it all pretty. The surfaces were roughened for the flox too which went on after a thin coat of epoxy.

Rather than making a smaller backing plate and covering it with BID, I’ve gone for plates full size. The twisting forces will now transfer to the top surface of the canard so all I have to do is secure the plate to the tab and it will be …super secure.

You can see the hardware in pic 1. Those AN3-55A are not cheap and it looks like a -54 would work better! I had to get a drilled one as undrilled were o/s and really …its mainly in shear.

Pic 3 has the canard secured. Oh and did I mention another 5 hours or so of sanding the canard profile. I don’t even want to talk about it or log it. Looks like that is pretty much done too.

Pieces ready

Floxed in place

Canard secured

 

Date:  05-24-2016

Number of Hours:  5

Manual Reference:  12-1

Having installed the canard alignment pins per plans I’m now doing a modification. The issue is that if the joins around the canard fitting are close and tight you can’t get the canard off. Doh!

So where the pins go I’ve drilled all the way through to the longeron doubler, Pic 1. Of course I had carefully rounded that off and now we need a square end here. I added some spruce and a little fox filler and covered the lot with one ply of BID. After this I drilled through again from F22.

You can see in pic 2 the need for more spruce with a thin aluminium tube in place to hold the AN3 size bolt.

Pic three shows that I’m going to use a spare set of the NC1 fittings I happened to have (over ordered!) and how its all going to fit together.

Drilling out for the pins with a long bit

The need to restore the spruce

Hardware showing

 

Date:  05-18-2016

Number of Hours:  15

Manual Reference:  12-2

This was done over many days with many steps. The attachments had AN3 size bolts so that had to be carefully drilled out to AN4. I then reinstall with AN4s and all was good.

Then the canard comes off and the holes in F22 have to be drilled out for the CN1 bushings. You can see in Pic one I’ve made up a simple jig using hot glue and a long drill with extension. Plans have you doing this before the nose guts go on so of course there is an issue with drilling. I used the ‘spot face’ from the wing install. It worked nicely.

Then comes fitting the inserts as they are oversized. Thats a lot of careful grinding. You can see in pic 2 one of them in place. I marked with texta to ensure they went back as they came out each time. One side needed a slight slant.

Next up was glassing over the front of the inserts which I did with the canard on and clamped in place. Then the hole gets opened out. Yep another cure cycle.

I made up nut plates on the AN970-4 washers as you can see in Pic 2 and added four holes for ‘flox fingers’. Its a bit hard to find this step in the plans. Its actually on the A7 sheet rather than in writing. The specified nutplate ears on the K1000-4 were too near the edges of the big washer so I used MK1000-4 instead.

Pic 3 shows that I’ve put glass over the nut plates as well as flox. I used two ply of glass instead of one per plans. There is a lot of turning force on the tight nuts so my call to add a little here. It is rock solid.

Drilling out for the inserts

Captive nutplates

2 ply and flox retrainer

 

Date:  05-16-2016

Number of Hours:  10

Manual Reference:  12-1

Having done the pins a while ago time for the tabs. I’ve just made them per plans. Some high density foam 5mt glued on. OK I did tidy up the set glue before glassing them.

I did the two sides in separate cures. One had a bubble in it so of course I ground it off and did it again. After cure I trimmed the edges as you’d expect.

Foam 5mt glued in place

Inside layup

Done

Date:  06-29-2015

Number of Hours:  5

Manual Reference:  12-1

Finally good to drill out the 3/16″ holes for the canard attachment. The question is how to you drill straight ‘square’ holes in this position? Yes we all know the holes get drilled out later for AN4’s.

As I had a nice long drill bit the answer was to make a guide as you can see in the pics. I’ve just bondoed it on to the side. I did clamp a block on F22 as you can see in pic 1 so I had somewhere flat to put the set square for lining up the bit as you see in pic 2.

Yeah I took most of the day rechecking the canard position to drill these two holes. I’m happy enough to take the small victories.

Jig in place

Lining things up

Drilling a straight hole

Date:  06-27-2015

Number of Hours:  10

Manual Reference:  12-1

A couple more days on this and I had to admit that I really do have to re-profile the canard. I decided however to install it with the 3/8″ bolts as close as I can. The idea is that if its stable then I can get the incidence right with the canard locked in place. I’m not sure yet if I’ll do the upper tabs as they will interfere with sanding. I’ll see how stable it is with just the tabs first.

I spent some hours getting the garalite blocks close to the correct angle and floxed in. It was just a bit untidy and I decided on one ply of BID over the top and with the canard tabs secured while it cured. This will fill up any small gaps in the flox and make me feel better in having a nice even surface for the canard tabs to bear down on.

Now I still need to recheck and then clamp it all up and do the 3/8″ holes through the canard tabs into F22.

What I have done as well is get an exact reference on the canard sides with the digital level on a marked place on each longeron. I will be able to exactly duplicate these numbers and photos of the spirit level bubble as a back up. With these if I don’t get the incidence sorted in the hangar, I will be able to get it correct back at my home workshop.

More incidence

Foil layup

Blocks in place

 

Date:  06-25-2015

Number of Hours:  10

Manual Reference:  12-1

More fun setting up. I checked the sweep with angle iron and its spot on. I will check again at the center-line although checking at the spar and wing makes more sense. The top of the canard and the top of the CS Spar at the firewall match at 0.00 so thats something.

The incidence is closer with wedges per plans and rather than making a temporary wedge, drill holes and then making the real wedge out of glass. I went with some G11 Garolite which is fiberglass epoxy laminate sheet and floxed them in place. This was a few days fiddling and I’m still NOT happy with the incidence.

After a lot more sanding and checking, it seems I’m running out of the 410 filler I put on and its getting close to needing another coat. This means all the hours of profiling are gone and I’m back to the start. The difference is that I have the wing incident blocks to get my exact reference.

Another big thing is to support the canard by the tabs. Secured on a bench induces a slight twist in my experience. That’s my excuse anyway.

Sweep check

Incident wedge

Curing the wedgies with heat

Date:  06-24-2015

Number of Hours:  10

Manual Reference:  12-1

I’ve spent 6 days this week full time on the canard install without much to show really. It took a day to cut away the fuselage sides to fit the canard and then when I lined up the incidence it was close but not right over the canard’s length.

I’m very determined to get this right. I have the wings set up and they worked out really well. Incidence unsupported is .05 down one side and .05 up the other so I’m within 0.1 of a degree after all the work. Now I need to match the canard profile with this while I have the chance with the wings on and everything setup.

When I removed the wing supports I got .02 movement but what I’m able to do is just lower the fuselage to get my zero again. Now to set the canard perfectly.

It turns out to have a slight twist and mismatch where I’ve profiled the top. Now I can really see where it sits. So I got to it with my sanding block and level. Many hours passed over a few days….

Incident check

Check again

Alignment laser check for fun

 

Date:  02-11-2015

Number of Hours:  3

Manual Reference:  12-1

Plans say this is a half hour job so three hours is about right for me. I really spent most of the day reading about the canard installation overall. So thats the Long EZ plans, the Roncz plans and the Cozy plans to read through as well as info on file that I’ve collected and the ‘Unblessed Word’… a canard document of tips that I check at every step. Its a David Orr thing…

The alignment pins need to be at right angles to F28 which is sort of interesting as then the pin holes are going to be on a bit of an angle going into the longeron doubler. Obviously (reading the plans helps with the obvious) the pins need to be straight to the canard. I am thinking about the mod where these pins are removable however I’ll begin with the plans method and just drill this out if I go the other way. Its the same holes and alignment.

I made a drilling jig… a thick bit of wood with a hole in it done on my drill press… to keep the drill bit straight and went progressively with a 1/8″ bit all the way up to the #10 which is just a hair bigger than 3/16″. Thats the first pic. Pic 2 shows me drilling straight but noticing the curve in the longerons.

Pic 3 show the AN3-20A that I cut the bolt head off per plans. So now they slip in and out OK and will be microed in much later or discarded if I go the removeable bolt option. All good and it ate up another day.

 

Drilling jig

Square to what?

Alignment pins