Epoxy Wipe

The cool thing about using the epoxy wipe method of finishing is you don't have to have a perfect surface to start with.  You do have to have your perfectly desired shape, but the scratches and pin holes are no worry.

I use West and microballoons.  First, lay it on thick.

After 3-4 hours it's ready for the "cheese grater" surform file to knock off the high spots. It's best to get started now.  If you wait overnight the filler will be harder to work with. Keep whittling away until you can can just see the glass start to appear, now stop.  Come back tomorrow and start sanding with 36 grit paper. Work on the shape.

When it takes on the desired shape and form, do a last pass with 80 grit paper.  Now, you're done with sanding!

Now it's time for the epoxy wipe.  Use pure West epoxy.  First, used compressed air to thoroughly blow off all the dust out of the pin holes. BTW, some of my "pin holes" are almost 3/8" across!

For the first pass, we used about seven squirts worth.  Squeegee it on, and spread it as thin as you possibly can.  Wait 20-30 minutes and repeat.  The second pass we only used three squirts, for subsequent passes we only needed two. For the underside of the canard, and the inside face of the wheel pants, we gave it four coats.  I may use six for the upper surface.

Click on this photo and you can see how big the pinholes are. They are all perfectly filled.

After we did all this, I installed the brakes. Tomorrow we'll sand the epoxy with 220 grit to ready it for primer. Then the Big Deal - get ready to install the canard!

Picking Up Speed

I am moving into the mad rush mode. The project is picking up steam, but so is the calendar.  One big unknown is getting hold of a prop.

The brakes are just about ready, I just have to work on the brake covers before I can apply filler to the wheel pants.

Before we mount the canard into the fuselage, I wanted to get as much of the underside finished as possible. When we did the canard layups we applied peel ply to help smooth the surface.  For the last six months Pat has been dying to peel if off.  Today was his big day.

Once the peel ply is up, I can see that the canard surface really looks good.  

Next comes mixing the filler.  I used West System epoxy mixed with microballoons. Again, Pat helped a lot.

When a batch is ready, I dump it on the surface, then use a small squeegee to press it in, just to get a decent bond.  Then I go back with a 12" drywall knife to pull it as smooth and as uniform as possible.  This section here probably had 5 batches applied.

This is what it looks like after the micro filler epoxy has been applied. After it cured about 4 hours I start working it.  It's better to start ASAP, rather than waiting a day or two, since the filler hasn't yet developed it's full strength. I start with a curved Stanley Surform file and make lots of dust.

After a while I start to use my two foot sanding board with 36 grit paper.  As the job progresses, I like to mark up the surface with a carpenter's pencil. As I sand, it highlight the high spots, so I know where I need to concentrate.

The idea is to keep sanding until the fiberglass is just starting to show through the filler. About two hours after I started, it's looking better better, but I am bushed.  I think I laid the wet filler on a little thick, which resulted in extra sanding.  I'll try and make it a little thinner when I wort the upper surface.

Finally added something, rather than taking away.

Did a trial fit of the canard today. It felt good to be putting something on to the plane, rather than grinding things off.

The Air Venture Cup Race is just a few weeks away and it seems like I have an impossible amount of work to do.  The odds are against me being able to run the race, but this week was the deadline to apply, so I figured no harm.

Step by Step, Inch By Inch

Spent the last couple of days grinding away the paint and stuff that needs to be removed, prior to installing the new canard.  I also had a fairly large screw-up.  As I mentioned in the previous post, I accidentally sawed through the aluminium fuel line that is used to transfer fuel from the main tank to the header tank. C-Rod would call that a beer penalty.

I went to drill out the old fuel line, and wound up boring a hole through the bottom of the fuel tank. On, my back!  So yesterday, the main focus was fixing that mess up, plus a couple of other things.

Today I hope to do a trial fit of the canard into the fuselage and see what needs to be done to bring the two together.

Removing the canard

Big day, major surgery, I finally removed the broken canard.  Would you call that a canardodectomy?  I tell you what, that sucker didn't come out without a fight.

First, I leveled the airplane then made templates to establish the flight level condition.  These will be critical to get the proper alignment when I install the new canard.

Making the first cut, with Mr. Sawzall.

After a couple of hours of wrangling it's finally breaking loose.  We had to take an hour off because I accidentally cut through the main fuel tank supply line.  there was about a gallon and a half of fuel left in the tank, so we had to wait for it to drain and dry out.

Smiling on the outside - crying on the inside.

It's out.  Pretty sad, really, for a hunk of Styrofoam and fiberglass..  A couple hundred people had their feet rest on the passenger's side when I gave them rides.  Only one set of feet on the pilot's side.

More Detail on Making Wheel Pants.

In the Quickie Aircraft plans, they have you make the wheel pants as a couple of straight-sided items, as seen her in Paul Fisher's beaut.

Air doesn't like to flow in a straight line around an object. There has been a lot of work done on pressure recovery wheel pants, and I thought it would be a good idea to take a clue from the guys working in this area.

So, the problem becomes, how to make a pressure recovery type pant with our little birds that use the pant itself to support the weight of the aircraft?  For the shape, I went to a set of RV-7 wheel pants and tried to emulate that shape. The way I approached it, was to build the interior of the plant per QAC plans. That way I knew it'd be structurally sound.  Once the slab sides are complete, I would build up the outside of the pant for the improved aerodynamics.  This would be a great place to use a wind tunnel and scale models, but unfortunately, that's not my bailiwick.

Again, I started out making the regular wheel pant structure, including the brakes and axle hard points.  I then fitted the wheel in place.  The brake calipers will be buried in the foam for the time being.

Next, using two part expandable foam, I glue Styrofoam scraps all over the wheel pant, giving it a slightly unaerodynamic shape. The idea is to build up enough for carving.

Now using a couple of templates as a guide, I get out my trusty Milwaukee Sawzall and start whittling away at it. I try to go slow and slice off a little at a time. Just like carving a turkey.  Keep your broom and trash can handy.

Here are a couple of videos showing more about my Sawszall art carving methods.

Part 1

After flipping the canard onto it's back, here is Part 2.

Sam - Put Your Pants On!

I've been making some progress getting the new wheel pants fabricated and installed. First, I made the hot wire templates and installed on a block of foam. (As always, click on the photo to see the detail.)

Two cores are cut out, left and right.

Plywood hard points are installed in a 1/4" piece of white foam.  These hard points are reinforced with extra layers of glass.  The one in the center is for the axle, the one at the left is to mount the brake caliper.

I rigged up a simple vacuum bag setup which did a nice job of pulling the foam flat and sucking out excess epoxy.

Here, one of the wheel pant covers has been attached to the foam core. A similar cover is attached to the other side of the pant core.

The trick is to properly line up the wheel pants to give the proper toe-out and camber. I used David Gall's white paper to establish the proper numbers.  We took a cheap laser pointer and taped it to a tripod and first set it up so it would shoot through both wheel pants. That established our baseline.

Then we mounted a board at the center point of the canard and drilled a hole which was our target, again using David Gall's numbers.

Target board.

Once we were satisfied with the position, we used epoxy micro to lock it in place.  We used a hot glue gun and stirring sticks to hold everything in place until it cured.

 Major assistance was provided by Jerry Marstall and Pat McGuire.

 Now we're getting somewhere. a couple of days later the axle, wheel and brake caliper are installed.

 

Bill Hunter was kind enough to come over and help me flip the canard. The next major jobs will be carving and final glassing of the wheel pants, to a nice aerodynamic shape.

 While Jerry was here he directed fabrication of the collapsible Quickie Tail Cradle. This will greatly simplify tail removal.  Wish I had this 20 years ago.

Will I make to Oshkosh?  Stay tuned.

Starting the Wheel Pants.

I made some special off-plans templates for the wheel pants.  I am attempting to create pressure recovery type pants, but of course, the big challenge is adapting PR pants to the wing attachment. It was wet, raining and cold in the hangar, so we set up shop in the nearby T-hangar pilot's lounge.

Here, we are establishing the cutting pattern to make the two wheel pants.  There is both a left and a right pant, they are slightly different.

After the first core is cut, it left an interesting block of foam. Here the second pant is ready for hot wiring. They turned out pretty well.  By the way, that's a 2008 AirVenture poster in the background, featuring the Aeroshell cow, Amoolia. The poster is autographed by famous race pilot and altitude record setter, Bruce Bohannon.

Catching up

A lot has transpired since my last update.  Progress is slower than hoped, but we did take a month's worth of vacations already this year.

Here is what my Quickie looks like right now. Sad.

Now that the main portion of the canard is done, it's time to attach the elevators.  This was pretty tricky, since I didn't have the right jigging template available. Pat is helping me keep lined up. The phenolic bearing blocks are attached with 2 BID.

Now it's time to install the slot cores. This is done by using the elevators to establish the position. I stuffed shop towels under the elevators to help exert pressure.  I used micro slurry as the interface, but wonder if pour in foam might be better.

Slot cores are now sanded smooth, getting ready for glassing.

A slot is routed out for the brake lines, then covered with dry micro.  I'll do the same thing on the opposite side for the pitot and AOA lines.

I discovered a few voids in the slot core/spar joint, so I dug it out, roughed up the spar, and filled it with two-part foam.

Here is the garage that I was able to use while building the canard.  It was a great help in the cold months, but now it's time to move back to my hangar.

Finally!

 Plastic Explosive - meet your new canard!

Work starts right-away.  Two lines are routed for the pitot and the Angle of Attack indicator.